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                    UNIVERSIDADE FEDERAL DE ALAGOAS
INSTITUTO DE CIÊNCIAS BIOLÓGICAS E DA SAÚDE
Programa de Pós-Graduação em Diversidade Biológica e Conservação nos
Trópicos

DANIELE SOUTO VIEIRA

ESTRUTURA FUNCIONAL DE COMUNIDADES DE PEIXES MARINHOS COSTEIROS
DO ATLÂNTICO SUL OCIDENTAL

MACEIÓ - ALAGOAS
JUNHO/2024
1

DANIELE SOUTO VIEIRA

ESTRUTURA FUNCIONAL DE COMUNIDADES DE PEIXES MARINHOS COSTEIROS
DO ATLÂNTICO SUL OCIDENTAL

Dissertação/Tese apresentada ao Programa de PósGraduação em Diversidade Biológica e Conservação nos
Trópicos, Instituto de Ciências Biológicas e da Saúde.
Universidade Federal de Alagoas, como requisito para
obtenção do título de Mestre/Doutor em CIÊNCIAS
BIOLÓGICAS, área de concentração em Conservação da
Biodiversidade Tropical.

Orientador(a): Prof(a). Dr(a) NÍDIA NOEMI
FABRÉ

MACEIÓ - ALAGOAS
JUNHO/2024

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Catalogação na fonte
Universidade Federal de Alagoas
Biblioteca Central
Divisão de Tratamento Técnico
Bibliotecária Responsável: Lívia Silva dos Santos - CRB 1670
V657e

Vieira, Daniele Souto.
Estrutura funcional de comunidades de peixes marinhos costeiros do atlântico sul
ocidental / Daniele Souto Vieira. –2024
66 f.:il.
Orientadora: Nídia Noemi Fabré.
Tese (Doutorado em Ciências Biológicas) – Universidade Federal de Alagoas.
Instituto de Ciências Biológicas e da Saúde. Programa de Pós-Graduação em
Diversidade Biológica e Conservação nos Trópicos. Maceió, 2024.
Bibliografia: f. 61-65
1. Ecossistemas costeiros. 2. Comunidades de peixes. 3. Diversidade taxonômica.
I. Título.
CDU: 574.2

PRÓ-REITORIA DE PESQUISA E PÓS-GRADUAÇÃO (PROPEP)
Av. Lourival Melo Mota, S/N, Tabuleiro do Martins, Maceió - AL, Cep: 57072-970
(82) 32141069 EMAIL: cpg@propep.ufal.br

PROGRAMA DE PÓS-GRADUAÇÃO EM DIVERSIDADE BIOLÓGICA E CONSERVAÇÃO NOS TRÓPICOS
ATA DE DEFESA DE TESE DE DOUTORADO
DE PÓS-GRADUAÇÃO STRICTO SENSU
ATA Nº 24

Ata da sessão referente à defesa intitulada “Estrutura funcional de comunidades de peixes marinhos do Atlântico Sul
Ocidental”, para fins de obtenção do título de Doutor em Ciências Biológicas na área de Biodiversidade, área de
concentração Conservação da Biodiversidade Tropical e linha de pesquisa em Diversidade e ecologia de
organismos tropicais, pelo(a) discente Daniele Souto Vieira (início do curso em 01/03/2020) sob orientação da
Profa. Dra. Nídia Noemi Fabré/UFAL.
Ao vigésimo oitavo dia do mês de junho do ano de 2024 às 08 horas, online, reuniu-se a Banca Examinadora em
epígrafe, aprovada pelo Colegiado do Programa de Pós-Graduação conforme a seguinte composição:
Dr.(a) Presidente – Nídia Noemi Fabré/UFAL
Dr. (a) Lucas Augusto Kaminski
Dr. (a) Ronaldo Angelini
Dr. (a) Ezequiel Mabragaña
Dr. (a) Guilherme Ramos Demétrio Ferreira
Tendo o(a) senhor(a) Presidente declarado aberta a sessão, mediante o prévio exame do referido trabalho por parte
de cada membro da Banca, o(a) discente procedeu a apresentação de seu Trabalho de Conclusão de Curso de Pósgraduação stricto sensu e foi submetido(a) à arguição e avaliação se o trabalho contém produção científica para gerar
artigo em periódico P≥50 pela Banca Examinadora que, em seguida, deliberou sobre o seguinte resultado:
( X)
APROVADO.
( )

APROVADO CONDICIONALMENTE, mediante o atendimento das alterações sugeridas pela Banca
Examinadora, constantes em formulários em anexo a esta Ata.

( )

REPROVADO, conforme parecer circunstanciado, registrado no campo Observações desta Ata e/ou
em formulários em anexo a esta Ata., elaborado pela Banca Examinadora.

Observações da Banca Examinadora (caso não inexistam, anular o campo):

Nada mais havendo a tratar, o(a) senhor(a) Presidente declarou encerrada a sessão de Defesa, sendo a presente Ata
lavrada e assinada pelos(as) senhores(as) membros da Banca Examinadora e pelo(a) discente, atestando ciência do
que nela consta.

Dr.(a) Presidente – Nídia Noemi Fabré/UFAL

Dr. (a) Ezequiel Mabragaña

Dr. (a)

Dr. (a) Ronaldo Angelini

Lucas Augusto Kaminski

Daniele Souto Vieira

Dr. (a) Guilherme Ramos Demétrio Ferreira

Pró-Reitoria de Pesquisa de Pós-Graduação – UFAL

DEDICATÓRIA
Dedico esta tese aos meus pais e meu irmão em primeiro lugar. E dedico
também aos meus amigos, que estiveram comigo durante o caminho.

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AGRADECIMENTOS
Agradeço inicialmente aos meus pais por todo amor e incentivo sempre. Muito
obrigada por considerar a educação como prioridade e por me ensinarem que o
trabalho duro, responsabilidade e respeito ao próximo e são tão ou mais importantes
quanto um diploma. Obrigada por me darem um irmão e uma família para onde voltar
quando eu tiver momentos difíceis.
A minha orientadora professora Dra. Nídia e ao professor Dr. Vandick, pela
paciência e pela vontade de contribuir pela formação de seus alunos.
Aos melhores companheiros de laboratório Ivan, Gilmar, Mônica, Myrna,
Diogo, Jordana, Jessika, Ana, Leticia, Erik, Cézar e Jana muito obrigada pelas
contribuições acadêmicas e risadas que tornaram o trabalho muito mais leve e
divertido. Obrigada especial ao meu amigo Victor por toda ajuda e incentivo sempre
fundamentais, obrigada por dividir seu conhecimento e fofocas comigo. Aos amigos
acadêmicos Karol, Ciro, Beth que se tornaram amigos de vida. Aos meus amigos de
longa data Sara, João, Jeferson, Carla, Lilian, Eduardo, Alê e Danilo, obrigada pela
amizade, jantares e pelo ombro para eu chorar. Amigos são a família que a gente
escolhe e é bom demais ter a companhia de vocês.
Agradeço à Universidade Federal de Alagoas e ao Programa de Pósgraduação em Diversidade Biológica e Diversidade no Trópicos (PPG- DIBICT), em
especial a Julienne por toda a paciência com os alunos. Também agradeço à
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e ao
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) pelo apoio
financeiro financiamento da pesquisa, fundamentais para meu crescimento
acadêmico.
Muito obrigada!
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RESUMO
As comunidades de peixes marinhos costeiros desempenham um papel importante
na produtividade, a estabilidade das cadeias alimentares e conectividade entre
habitats, sendo fundamental na funcionalidade dos ecossistemas marinhos. No
Atlântico Sul, a estrutura das comunidades é resultado de fatores como as dinâmicas
de descarga dos rios, a precipitação e a disponibilidade de recursos, que pode
influenciar não só a composição, mas a diversidade funcional dessas comunidades.
Compreender a estrutura funcional dessas comunidades é essencial não apenas para
a gestão sustentável dos recursos, mas também para a conservação eficaz dos
ecossistemas costeiros. Nesse contexto, a pesquisa investiga a diversidade
taxonômica e funcional e os fatores que influenciam as comunidades de peixes em
ambientes costeiros lodosos no Atlantico Sudoeste Sul. Os resultados revelam
diferenças significativas na composição taxonômica entre as áreas estudadas,
explicadas em parte pela distribuição dos estuários da região. A presença de
diferentes pools de espécies ao em áreas costeiras resulta em padrões diversos de
biodiversidade de peixes, indo além da simples riqueza e abundância de espécies.
Esses achados contribuem para uma melhor compreensão da estrutura e dinâmica
das comunidades de peixes em ambientes costeiros lodosos. Além disso, a análise
dos dados em escala regional demonstra padrões distintos de distribuição e
composição das espécies ao longo das províncias do Sudoeste do Atlântico Sul,
indicando a influência de fatores ambientais e biogeográficos na estrutura taxonômica
e funcional das comunidades. Esses resultados podem contribuir significativamente
para o conhecimento da ecologia marinha na região e fornecendo subsídios
importantes para a conservação da biodiversidade marinha no na região.
Palavras-chave: peixes costeiros, estrutura funcional, ambientes tropicais
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ABSTRACT
Coastal marine fish communities play an important role in productivity, food chains
stability and connectivity between habitats, being fundamental in the marine
ecosystems functioning. In the South Atlantic, the structure of communities is a result
of river discharge dynamics, precipitation and resource availability, which can
influence not only the composition, but the functional diversity of these communities.
Understanding the functional structure of these communities is essential not only for
sustainable resource management, but also for the effective conservation of coastal
ecosystems. In this context, the research investigates the taxonomic and functional
diversity and the factors that influence fish communities in muddy coastal
environments in the South-West Atlantic. The results reveal significant differences in
the taxonomic composition between the areas studied, explained in part by the
distribution of the estuaries of the region. The presence of different pools of species
in coastal areas results in different patterns of fish biodiversity, going beyond the
simple richness and abundance of species. These findings contribute to a better
understanding of the structure and dynamics of fish communities in muddy coastal
environments. Furthermore, analysis of data on a regional scale demonstrates distinct
patterns of species distribution and composition throughout the southwestern
provinces of the South Atlantic, indicating the influence of environmental and
biogeographic factors on the taxonomic and functional structure of communities.
These results can significantly contribute to the knowledge of marine ecology in the
region and provide important subsidies for the conservation of marine biodiversity in
the region.
Key words: coastal fish, functional structure, tropical environments

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LISTA DE FIGURAS

Figure 1. Map of the study area located in the Tropical Southwestern Atlantic,
showing the sampling locations (black dots)..Map of the study area located in
the Tropical Southwestern Atlantic, showing the sampling locations (black dots).
................................................................................................................... 27
Figure 2. Multidimensional scaling (nMDS) applied to the similarity matrix of the
collected species illustrating the significant differences in composition between
three identified regions (NBS – Northern Brazil Shelf; TSA-N – North of the
Southwestern Tropical Atlantic; TSA-S – South of the Southwestern Tropical
Atlantic). ..................................................................................................... 31
Figure 3. Analysis of similarity in species composition among samples, showing
regional differences throughout the Neotropical Atlantic and the three regions
identified in our study (A – North of the Southwestern Tropical Atlantic; B –
Northern Brazil Shelf; and C – South of the Southwestern Tropical Atlantic).32
Figure 4. Diversity profiles as a function of order q for ordinary Hill numbers (A), and
functional Hill numbers (B), where NBS – Northern Brazil Shelf; TSA-N – North
of the Southwestern Tropical Atlantic; and TSA-S – South of the Southwestern
Tropical Atlantic.......................................................................................... 33
Figure 5. Similarity in species composition (A) and trait composition (B) of fish
species inhabiting coastal muddy bottoms along the Neotropical South Atlantic
(NBS – Northern Brazil Shelf; TSA-N – North of the Southwestern Tropical
Atlantic; TSA-S – South of the Southwestern Tropical Atlantic). ................ 35
7

Figure 1. Study area showing Southwestern Atlantic coast with the provinces
according Spalding et al. (2007). Also, the graphic shows environmental
changes expected along the gradient in the área. ..................................... 51
Figure 2. Similarity in taxonomic composition (A) and trait composition (B) of fish
species among the four provinces along the latitudinal gradient of Southwestern
Atlantic coastal waters.. ............................................................................. 56
Figure 3. Proportions of traits represented in fish assemblages of coastal waters of
four provinces in the Southwest Altantic..For maximum body length – S= small,
M= medium, L= large, and XL = extra large; for habitat – F&E= fresh water and
marine species; E= estuarinetuarine, E&M= estuarine and marine, M= marine;
for parental care B= bearers, G= guarders, Mt= maternal care, N= no parental
care; for diet – De= detritus, Al= algae, Pl= plankton, In= invertebrates, I&F=
invertebrates and fish, Om= Invertebrates and plants, Ca= only fish, Pi= fish and
other vertebrates (birds and turtles)........................................................... 57

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LISTA DE TABELAS

Table 1.

Description and interpretation of the traits used for the functional

characterization of species collected throughout the Neotropical South Atlantic.
................................................................................................................... 28
Table 2. Estimated marginal means (EMMs) applied as a post-hoc test to detect
significant differences in biodiversity dimensions among identified regions (NBS
– Northern Brazil Shelf; TSA-N – North of the Southwestern Tropical Atlantic;
TSA-S – South of the Southwestern Tropical Atlantic). ............................. 34
Table 1. Functional traits used to estimate the functional diversity of fish species along
the marine systems of the South-Western Atlantic. ................................... 53

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SUMÁRIO
1.

APRESENTAÇÃO............................................................................... 11

2.

REVISÃO DA LITERATURA ................................................................ 12
2.1. Estudos biogeográficos ...................................................................... 12
2. 2 . Condições abióticas do Atlântico Sul .............................................. 14
2. 3. A diversidades taxonômica e funcional ............................................ 16
2. 4. Referências ......................................................................................... 18

3. CAPÍTULO I: Biodiversity dimensions of fish communities inhabiting coastal
muddy bottoms in the Tropical South Atlantic ............................................. 21
3.1. Introduction .......................................................................................... 22
3.2. Materials and methods ........................................................................ 25
3.2.1. Study area .......................................................................................... 25
3.2.2. Data acquisition and species classification ......................................... 26
3.2.3. Diversity measures and statistical analysis ......................................... 28
3.3. Results .................................................................................................. 31
3.4. Discussion ............................................................................................ 35
3.5. Acknowledgements .............................................................................. 40
3.6. References ............................................................................................ 40
4.CAPÍTULO II: Assessing functional composition patterns in fish communities
along the South-Western Atlantic............................................................. 47
4.1. Introduction .......................................................................................... 48
4.2. Materials and methods ........................................................................ 50
4.2.1. Data acquisition and dataset creation ................................................. 50
4.2.2. Functional traits of fish species ........................................................... 52
4.2.3.Statistical analysis ................................................................................ 54
4.3. Results .................................................................................................. 55
4.4 Discussion ............................................................................................. 57
4.5. References ............................................................................................ 61
6. CONCLUSÃO ........................................................................................ 66

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1. APRESENTAÇÃO

As comunidades ictiicas costeiras representam um componente essencial dos
ecossistemas costeiros, pois desempenham um papel importante na composição da
biodiversidade, estabilidade das cadeias alimentares, manutenção da cadeia
pesqueira e funcionamento ecossistêmico marinho. No Atlantico Sul, a estrutura e
composição funcional dessas comunidades é determinada pela interação de fatores
bióticos e abióticos, ligadas principalmente às dinâmicas de descarga dos rios,
precipitação e disponibilidade de recursos. Todas essas características somadas aos
atributos funcionais das espécies, podem limitar a distribuição, a abundância e
composição das comunidades. Por Isso, compreender essa estrutura é vital para a
gestão sustentável dos recursos pesqueiros e para a conservação das funções
ecossistêmicas. Tendo em vista a importância dessas comunidades, este estudo visa
analisar a estrutura funcional das comunidades de peixes no Atlântico Sul,
identificando os principais fatores ambientais geográficos e biológicos que moldam
suas dinâmicas. A análise integrará dados ecológicos e funcionais para fornecer uma
visão abrangente das interações ecológicas que caracterizam essas comunidades.

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2. REVISÃO DA LITERATURA

2.1. Estudos biogeográficos
Estudos biogeográficos tentam explicar os padrões de diversidade e de
distribuição de espécies atuais e extintas desde a escala local até a escala global
(LOMOLINO, MARK V., RIDDLE, BRETT R., WHITTAKER, ROBERT J.; BROWN,
1998a). Para isso a biogeografia costuma atribuir padrões de distribuição de espécies
ao processo de mudança de temperatura, salinidade, e disponibilidade de alimento
(localmente), ou à eventos biogeográficos na escala temporal evolutiva, tais como
movimentos tectônicos e formação de barreiras (regionalmente). Todos esses
eventos em maior ou menor escala podem impedir ou facilitar outros eventos como
variância e dispersão, levando a diversificação da composição e riqueza de espécies
ao longo do globo. Apesar de parecer um tópico recente, a biogeografia começou a
ser discutida a partir de alguns estudos geológicos e de distribuição de espécies do
século 18 e foi impulsionada a partir de 1858 com as publicações de Darwin e Wallace
(LOMOLINO, MARK V., RIDDLE, BRETT R., WHITTAKER, ROBERT J.; BROWN,
1998b). De fato, Wallace é considerado o pai da zoogeogeografia por ter dedicado
sua vida a interpretar os conceitos da distribuição das espécies em um contexto
evolutivo, tendo levantado hipóteses como: o clima tem efeitos na distribuição, fatores
como predação e competição podem determinar a distribuição, assim como a
dispersão e extinção de espécies de vários grupos. Além disso foi responsável por
uma das primeiras divisões biogeográficas, incluindo algumas divisões batimétrica de
alguns arquipélagos (WALLACE, 1878a).

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Um dos primeiros trabalhos que buscou entender essas relações em
ambientes marinhos foi de (BRIGGS, 1974), onde foram definidas zonas
zoogeográficas e províncias marinhas a partir da taxa de endemismo dentro das
províncias. Mais tarde, em 2007, SPALDIN utilizou dados mais recentes para limitar
regiões biogeográficas marinhas em ambientes costeiros de plataforma continental
baseado na identidade das espécies e levando em consideração a evolução,
dispersão e isolamento. Assim, foram definidos reinos, províncias e ecorregiões como
framework para a conservação de áreas marinhas protegidas (SPALDING et al.,
2007a). Os reinos foram agrupados em polar, temperados e tropicais e subdivididos
por bacias oceânicas de cada região, totalizando 12 reinos. Já as províncias foram
definidas pela presença de biotas distintas com grande endemismo, e podem ser
consideradas como unidade de isolamento evolutivo já que essas divergências
decorrem das diferenças ambientais entre províncias. A menor unidade estabelecida
são as ecorregiões, estas têm o propósito de serem usadas para fins de conservação
e foram definidas pela similaridade da composição de espécies e os padrões
ecológicos podem ser mais visíveis (SPALDING et al., 2007).
Apesar da importância das definições dessas regiões de endemismo e da
consolidação do seu uso, estudos de biogeografia em ambientes marinhos podem
ser dificultados pela falta de conhecimento biológico das espécies e das suas
distribuições. Além disso, os fatores que influenciam as comunidades marinhas são
diversos e nem sempre estão disponíveis nas bases de dados, como por exemplo,
correntes, salinidade, profundidade, condição de fundo e barreiras (ACHA et al., 2004;
MIRANDA; MARQUES, 2011). A dificuldade de definir barreiras que limitem a
dispersão também pode ser um problema, especialmente porque as espécies
respondem de forma diferente às condições ambientais, e o que limita uma espécie
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pode ser irrelevante para outra. Por exemplo, para espécies autótrofas, a falta de luz
em grandes profundidades limita sua distribuição, mas não tem nenhum impacto em
espécies bentônicas (PEREIRA; SOARES-GOMES, 2002). Assim como as variações
de salinidade em ambientes estuarinos que podem limitar a entrada de espécies que
não tenham tolerância às variações de salinidade (BARLETTA, 2004a).
2. 2 . Condições abióticas do Atlântico Sul
A região do sudeste do Atlântico Ocidental é caracterizada pelas porções
tropicais, que inclui a plataforma Norte do Brasil e a plataforma tropical do Atlântico
Sudoeste (área que corresponde a foz do Amazonas até Santa Catarina no sul do
Brasil), e a porção quente e temperada que se estende de Santa Catarina no Brasil,
até a Península de Valdez no sul da Argentina (BRIGGS; BOWEN, 2012a; HALPERN;
FLOETER, 2008; SPALDING et al., 2007a) formando assim um gradiente ambiental.
Nessa região encontram-se 4 províncias Plataforma Norte do Brasil, Atlântico
Sudoeste Tropical, Atlântico Sudoeste temperado quente e parte da província
Magellanica que segundo SPALDIN (2007) divergem em sua biota devido as
diferenças nas características abióticas nas proximidades dos seus limites (ou seja,
na área de separação entre províncias). E entender como essas características
ambientais impactam a composição de espécies é importante para entender os
padrões de distribuição atual.
A província ao norte, próxima ao equador, tende a ser mais quente, sob a
influência de uma corrente quente (corrente do Norte do Brasil) somada a
variabilidade na temperatura, precipitação e área de cobertura manguezal sessa
região (VILAR et al., 2013a; VILAR; JOYEUX; SPACH, 2017), resultando no aumento
na riqueza e abundância das assembleias ictiícas da costa brasileira. A entrada do
grande volume das águas túrbidas do rio Amazonas também exerce influência nas
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comunidades estuarinas no Norte, onde se observa uma maior abundância de
espécies únicas se comparada com outros estuários no Brasil (VILAR et al., 2013a).
De forma semelhante, a presença da bacia amazônica é considerada o fator principal
na taxa de endemismo de 25% na plataforma Norte do Brasil e nas diferenças na
composição de espécies com o Caribe (BRIGGS; BOWEN, 2012b).
À medida que movemos em direção ao sul, a costa é marcada por uma
plataforma continental estreita, uma corrente quente e fraca (corrente do Brasil) flui
em direção ao sul. Além disso, a grande complexidade de habitats nos trópicos,
incluindo manguezais, recifes de coral e florestas tropicais, oferece às espécies uma
diversificação de micro-habitats e nichos, permitindo que elas coexistam (PIANKA,
1988, KOSTOLEV et al, 2005) e podendo aumentar a diversidade nessas áreas. A
dinâmica estuarina, a grande descarga de nutrientes e processos de estuarinização
também ajudam a sustentar essa diversidade em áreas costeiras (LONGHURST;
PAULY, 1987a), mas existem outros fatores que são importantes para as
comunidades. Essas regiões de transição entre as províncias e a descarga d’água
nos estuários, ou encontro de massas de água com os oceanos formam o que
chamamos de fronts, onde existem maiores variações de salinidade, densidade e
turbidez podendo funcionar como barreiras para as espécies estuarinas (ACHA,
EDUARDO M., ALBERTO PIOLA, OSCAR IRIRBARNE, 2015) e também para
algumas espécies recifais que podem utilizar os estuários no seu ciclo de vida como
Carangideos e Serranideos (FLOETER et al., 2008a).
A porção sul do Atlântico, que compreende a Argentina até a Terra do Fogo,
possui uma das plataformas continentais mais amplas e exibe uma confluência
oceanográfica entre a corrente do Brasil, que flui para o sul, e a corrente das
Falklands/Malvinas, que traz água subantártica fria do Sul e prevalecem fundos
15

arenosos com alta salinidade(COUSSEAU et al., 2020) . A temperatura diminui
juntamente com a precipitação e a entrada de rios nessa região, causando um
aumento da salinidade que pode limitar a distribuição da diversidade de várias
espécies de peixes (BARLETTA, 2004b) e pode ser uma restrição para algumas
espécies, reduzindo a biodiversidade.
2. 3. A diversidades taxonômica e funcional
A diversidade e riqueza de espécies têm sido usadas há décadas para entender
os padrões e fatores que influenciam a distribuição de espécies. De forma direta, a
riqueza é o número de espécies em uma comunidade e a diversidade é a função da
frequência relativa das espécies (KEYLOCK, 2005). Diante da quantidade de estudos,
foram definidos diversos padrões, tais como alta riqueza de espécies nos trópicos,
baixa riqueza em grandes elevações e a relação da diversidade com fatores abióticos
como temperatura, precipitação e salinidade (BARLETTA, 2004a; GASTON, 2000a).
Em ambientes marinhos os padrões latitudinais também são observados e são
influenciados também pela produtividade primária. Os ambientes costeiros tropicais
são conhecidos pela produtividade e complexidade de habitats e abrigam grande
diversidade de organismos estuarinos, recifais e marinhos (BARLETTA et al., 2010).
Essa configuração taxonômica se reflete nas características ecológicas, onde
normalmente se observa espécies de menor tamanho corporal e menor nível trófico
em resposta ao maior número de indivíduos disputando recursos (HAYDEN et al.,
2019).
A diversidade funcional é mensurada a partir de conjuntos de traços dos
organismos que têm influência direta em alguns aspectos do funcionamento
ecossistêmico, por isso, é considerada uma ferramenta importante para entender os
processos das funções ecossistêmicas (TILMAN, 2001). Os traços são características
16

morfológicas, fisiológicas e fenológicas que podem ser medidas em cada indivíduo e
que interferem em como as espécies vão performar determinada função
ecossistêmica (VIOLLE et al., 2007). As características morfológicas como o tamanho
das espécies são importantes para entender as várias dimensões da sua ecologia, e
por meio desses traços, é possível definir como as espécies se comportam, como se
adaptam e de que forma utilizam os habitats e seus recursos (SIBBING;
NAGELKERKE, 2000). Já os traços de história de vida estão ligados às estratégias
de reprodução das espécies. Por isso, avaliar as características de fecundidade,
comportamentos reprodutivos e cuidado parental, podem indicar questões ecológicas
como abundância e resiliência das espécies (LADDS et al., 2018).
Assim, quanto maior a diversidade de espécies (e de traços) espera-se maior
diversidade funcional (MICHELI; HALPERN, 2005). No entanto, as variações na
diversidade funcional podem depender da identidade das espécies e do conjunto de
seus traços, portanto comunidades com maior divergência nos seus traços são mais
diversas que comunidades com mais espécies (HALPERN; FLOETER, 2008; VIOLLE
et al., 2007). Em ambientes costeiros os padrões de diversidade estão relacionados
com diversos fatores, tais como as diferenças nas condições abióticas, e as perdas
de habitat e espécies (MOUILLOT et al., 2014a; PASSOS et al., 2016a).

17

2. 4. Referências
ACHA, E. M. et al. Marine fronts at the continental shelves of austral South America:
Physical and ecological processes. Journal of Marine Systems, v. 44, n. 1–2, p. 83–
105, 2004.
ACHA, EDUARDO M., ALBERTO PIOLA, OSCAR IRIRBARNE, H. M. Ecological
Processes at Marine Fronts: Oases in the Ocean. Spring, 2015.
BARLETTA, M. The role of salinity in structuring the fish assemblages in a tropical
estuary. Journal of Fish Biology, p. 1–28, 2004a.
BARLETTA, M. et al. Fish and aquatic habitat conservation in South America: a
continental overview with emphasis on neotropical systems. Journal of Fish Biology,
v. 76, n. 9, p. 2118–2176, 2010.
BRIGGS, J. C. Marine zoogeography. 1974.
BRIGGS, J. C.; BOWEN, B. W. A realignment of marine biogeographic provinces with
particular reference to fish distributions. Journal of Biogeography, v. 39, n. 1, p. 12–
30, jan. 2012a.
COUSSEAU, M. B. et al. The Magellanic Province and its fish fauna (South America):
Several provinces or one? Journal of Biogeography, v. 47, n. 1, p. 220–234, 2020.
FLOETER, S. R. et al. Atlantic reef fish biogeography and evolution. Journal of
Biogeography, v. 35, n. 1, p. 22–47, 2008.
GASTON, K. J. Global patterns in biodiversity. Nature, v. 405, n. 6783, p. 220–7, 2000.
HALPERN, B. S.; FLOETER, S. R. Functional diversity responses to changing species
richness in reef fish communities. Marine Ecology Progress Series, v. 364, p. 147–
156, 2008.
HAYDEN, B. et al. Biological and environmental drivers of trophic ecology in marine
fishes - a global perspective. Scientific Reports, v. 9, n. 1, p. 1–10, 2019.

18

KEYLOCK, C. J. Simpson diversity and the Shannon-Wiener index as special cases
of a generalized entropy. Oikos, v. 109, n. 1, p. 203–207, 2005.
LADDS, M. A. et al. Creating functional groups of marine fish from categorical traits.
PeerJ, v. 2018, n. 10, p. 1–27, 2018.
LOMOLINO, MARK V., RIDDLE, BRETT R., WHITTAKER, ROBERT J.; BROWN, J.
H. Biogeography. , 1998a.
LONGHURST, A. R.; PAULY, D. Ecology of tropical oceans. Academic Press, San
Diego, , 1987.
MICHELI, F.; HALPERN, B. S. Low functional redundancy in coastal marine
assemblages. Ecology Letters, v. 8, n. 4, p. 391–400, abr. 2005.
MIRANDA, T. P.; MARQUES, A. C. Abordagens atuais em biogeografia marinha.
Revista da Biologia, v. 7, p. 41–48, 2011.
MOUILLOT, D. et al. Functional over-redundancy and high functional vulnerability in
global fish faunas on tropical reefs. Proceedings of the National Academy of
Sciences, p. 1–6, 2014.
PASSOS, C. V. B. et al. Estuarization increases functional diversity of demersal fish
assemblages in tropical coastal ecosystems. Journal of fish biology, v. 89, n. 1, p.
847–862, 2016.
PEREIRA, R. C.; SOARES-GOMES, A. Biologia marinha. Rio de Janeiro:
Interciência, v. 2, p. 608, 2002.
SIBBING, F. A.; NAGELKERKE, L. A. J. Resource partitioning by Lake Tana barbs
predicted from fish morphometrics and prey characteristics. Reviews in Fish Biology
and Fisheries, v. 10, n. 4, p. 393–437, 2000.
SPALDING, M. D. et al. Marine Ecoregions of the World: A Bioregionalization of
Coastal and Shelf Areas. BioScience, v. 57, n. 7, p. 573–583, 2007.
TILMAN, D. Functional diversity. Em: Encyclopedia of Biodiversity. 3. ed. [s.l.]
Academic Press, 2001. p. 109–120.
19

VILAR, C. C. et al. Local and regional ecological drivers of fish assemblages in
Brazilian estuaries. Marine Ecology Progress Series, v. 485, n. Levin 1992, p. 181–
197, 2013.
VILAR, C. C.; JOYEUX, J. C.; SPACH, H. L. Geographic variation in species richness,
rarity, and the selection of areas for conservation: An integrative approach with
Brazilian estuarine fishes. Estuarine, Coastal and Shelf Science, v. 196, p. 134–
140, 2017.
VIOLLE, C. et al. Let the concept of trait be functional! Oikos, v. 116, n. 5, p. 882–892,
2007.
WALLACE, A. R. Tropical nature, and other essays. [s.l.] Macmillan and Company,
1878.

20

3. CAPÍTULO I: Biodiversity dimensions of fish communities inhabiting coastal
muddy bottoms in the Tropical South Atlantic

Daniele Souto Vieira1, Victor Emmanuel Lopes da Silva1, Adriano Caliman², José
Gilmar Cavalcante de Oliveira-Junior1, Victoria Judith Isaac Nahum3, Tommaso
Giarrizzo4, Thierry Fredou5, Nidia Noemi Fabré1.

1

Laboratório de Ecologia Peixes e Pesca – Universidade Federal de Alagoas, Instituto

de Ciências Biológicas e da Saúde, Maceió, Brasil
2

Departamento de Ecologia – Universidade Federal do Rio Grande do Norte, Centro

de Biociências, Natal, Brasil
3

Laboratório de Biologia Pesqueira e Manejo de Recursos Aquáticos – Universidade

Federal do Pará, Centro de Ciências Biológicas, Belém, Brasil
4

Instituto de Ciências do Mar – Universidade Federal do Ceará, Fortaleza, Brasil

5

Departamento de Pesca e Aquicultura – Universidade Federal Rural de Pernambuco,

Recife, Brasil

Abstract
This study provides insights into the intricate dynamics of coastal muddy bottoms
within tropical regions spanning from the Amazon to the São Francisco River estuary.
Through species analysis, distinct species pools distributed across the Tropical South
Atlantic have been identified, revealing diverse patterns in fish biodiversity that
transcend mere species richness and abundance, extending to their functional
21

composition. More precisely, significant variations in taxonomic composition among
the studied areas were observed, with differences in species composition and the
presence of exclusive species contributing to the rise of unique patterns in functional
diversity, partly attributed to differences in biogeographical provinces. Moreover, local
processes such as salinization and estuarization also play crucial roles in shaping the
taxonomic and functional diversity patterns within coastal muddy bottoms. By
acknowledging the distinctive characteristics and ecological significance of these
habitats, we can ensure the preservation of fish communities and uphold their crucial
roles as vital nursery and fishing grounds.

Keywords: functional structuring, coastal habitats, fishery grounds

3.1. Introduction
Information about biodiversity patterns is crucial to our understanding of the
functioning and conservation of ecosystems. The distribution and diversity of species
in different regions are shaped by evolutionary processes, as well as biogeographic,
climatic, and ecological processes (BANNAR-MARTIN et al., 2018; BARLETTA,
2004b; VILAR et al., 2013b). Investigating these patterns in specific habitats is crucial
for comprehending the mechanisms underlying biodiversity and its implications for
ecosystem dynamics, as well as anthropogenic stressor factors.
In the Tropical South Atlantic, for instance, the dynamics of biodiversity are
particularly intriguing due to the presence of unique environmental conditions and
biogeographic features (HENRIQUES et al., 2017b; SPALDING et al., 2007). The
22

region is characterized by two distinct provinces (the Northern Brazil Shelf and
Southwest Tropical Atlantic provinces), that exhibit contrasting climatic and
geomorphological characteristics, as well as three recognized barriers: the Mid
Atlantic Ridge, the discharge of the Amazon River, and the Benguela Current
(FLOETER et al., 2008) . These barriers influence species dispersal, promoting
allopatric speciation events, while occasionally allowing for connectivity and
metapopulation formation(IBAÑEZ et al., 2022).
The Northern Brazil Shelf province experiences a hot and humid climate, and it
is strongly influenced by the significant water influx from the Amazon River (GOUVEIA
et al., 2019). This discharge leads to increased phytoplankton biomass and
productivity, creating favorable conditions for fish species associated with muddy
bottoms. These fish species have adapted to thrive in turbid waters, relying on the
abundant organic matter and nutrients (BRIGGS; BOWEN, 2012c; VILAR et al.,
2013b). In contrast, the Southwest Tropical Atlantic province has a narrow continental
shelf, characterized by many smaller rivers that form estuarine systems with low
biological productivity (EKAU; KNOPPERS, 1999). Phytoplankton biomass in this
region is directly influenced by the flow of these small rivers, which fluctuates with
seasonal variations and precipitation levels (NETO et al., 2014). Consequently,
differences in productivity and isolation between these regions have a significant
impact on the assembly of aquatic communities, especially in coastal areas.
Among the various habitats within these regions, coastal muddy bottoms hold
particular ecological importance as they play essential roles as nursery and fishery
grounds. Muddy bottoms are characterized by high levels of organic matter, fine
sediments, and nutrient input derived from the animal’s excretion, bioturbation, and
decomposition of organic material from rivers and estuaries(MCLUSKY; ELLIOTT,
23

2004). These environments support a diversified macrofauna and contribute greatly to
coastal productivity. Furthermore, the detrital food chain operating in muddy bottoms
enhances nutrient cycling (Caliman et al. 2011), leading to the presence of a variety
of fish species associated with these environments (Loureiro et al. 2016; Ferreira et
al. 2019).
Understanding the dimensions of biodiversity on coastal muddy bottoms is vital
due to their crucial roles in providing shelter, food, and suitable conditions for
reproduction and early development of numerous species (MARTINHO et al., 2007).
These habitats contribute to the maintenance of fish populations and overall
ecosystem functioning, while also supporting local fisheries by harboring commercially
valuable species (AGUILAR-MEDRANO; VEGA-CENDEJAS, 2019; CAPEZZUTO et
al., 2020). However, studying diversity patterns within presents many challenges,
given the biogeographic differences discussed earlier. Variations in the total area of
the study, and the diversity of fishing methods employed in each region can hamper
the analysis and interpretation of biodiversity profiles (WIJERMANS et al., 2020).
Nevertheless, overcoming these issues and unraveling the mechanisms driving
community assembly in these habitats are critical for effective conservation and
management strategies.
Therefore, the primary objective of this study is to investigate the patterns in the
dimensions of biodiversity on coastal muddy bottoms within the Neotropical South
Atlantic. Specifically, we aim to assess the different components of taxonomic and
functional diversity (alpha and beta), focusing on understanding the effects of the
regional species pool on trait composition and functional space within the community.
By examining these patterns, we expect to obtain insights into the ecological

24

processes shaping the biodiversity of these essential nursery and fishery grounds,
assisting the development of effective conservation and management approaches.

3.2. Materials and methods
3.2.1. Study area
The study area encompasses the Neotropical South Atlantic, which is
considered a highly productive area, influenced by a wide set of environmental and
climatic factors. The North region is dominated by a humid tropical climate, where the
actions of two ocean currents (the North Brazil Current and the Guiana Current), and
significant tidal ranges are observed in its coastal environment (SILVA et al., 2021).
The productivity of the area is mostly influenced by terrigenous inputs, with the
discharge of the Amazon River forming a unique ecosystem along a large portion of
the coast(SMITH; DEMASTER, 1996). The coastal bottom and its wide continental
shelf are predominantly composed of sediments, mainly mud and sand, with few areas
of gravel and calcareous algae (NITTROUER; DEMASTER, 1986).
In the Tropical Southwest Atlantic province, the dominant climate is tropical dry,
with two well-defined seasons (dry and rainy) determined by the rainfall regime. This
region is dominated by the Brazil Current, the southern branch of the South Equatorial
Current (SILVA et al. 2021). The narrow continental shelf (between 20 and 50 km)
found throughout the area is characterized by the presence of large reef barriers, with
the substrate of the bottom dominated by terrigenous or organogenic sediments (sand
and mud). The productivity of the area is considered moderate, with the drainage of
continental waters influencing the narrow coastal strip (EKAU E KNOPPERS, 1999).

25

3.2.2. Data acquisition and species classification
A total of 29 sampling points were set throughout the Neotropical South Atlantic
(Figure 1). Each station was sampled with the assistance of their corresponding fleets
to ensure the representation of the captured fauna in the area. The fishing methods
employed in these regions exhibit considerable diversity, encompassing a wide array
of strategies and gear due to differences in the total area extent covered by each
fishing ground, and the size of the catch obtained.
For instance, in the Northern Brazil Shelf province, industrial-scale fishing
dominates, utilizing pair trawling techniques at depths ranging from 20 to over 60
meters. Conversely, artisanal fishing prevails in the Southwest Tropical Atlantic
province, characterized by an extensive fleet of canoes, rafts, and small motorized
vessels (up to 13 meters in length), working at depths ranging from 2 to 30 meters.
Nonetheless, for the present study, only data from trawl nets used in shrimp species
fisheries were included, as they are the main fishing strategy applied on muddy
bottoms (see Supplementary Information – Table S1).

26

Figure 1. Map of the study area located in the Tropical Southwestern Atlantic, showing
the sampling locations (black dots).Map of the study area located in the Tropical
Southwestern Atlantic, showing the sampling locations (black dots).

All collected individuals were transported to laboratory facilities to undergo
species identification and accurate morphometric recording. Subsequently, the fish
species were subjected to further characterization based on a comprehensive set of
eight functional traits (Table 1) associated with swimming efficiency, movement
capacity, feeding behavior, and habitat utilization (SIBBING; NAGELKERKE, 2000;
WATSON; BALON, 1984). To acquire this information, we used previously published
works, as well as online databases (such as the FishBase), except for the calculation
of the body shape index, which relied on the morphometric measurements obtained
directly from the collected individuals. In order to facilitate subsequent functional
analyses, a species-trait matrix was constructed using the compiled data.

27

Table 1.

Description and interpretation of the traits used for the functional

characterization of species collected throughout the Neotropical South Atlantic.

Habitat use

Morphological

Trophic

Functional traits

Variable
type

Categories

Ecological
meaning

Mouth angle

Categorical

Bottom, top and terminal

Catchability of
prey

Type of
dentition

Categorical

Flat, canine, conical, fused,
incisor, molariform, nodular,
triangular, tricuspid, villiform

Catchability of
prey

Trophic guild

Categorical

Herbivores, sessile invertebrates,
mobile invertebrates, mobile
invertebrates and detritus, mobile
invertebrates and fish, piscivores
and planktivores

Diet

Aspect-ratio
of caudal fin

Continuous

-

Swimming
efficiency

Body shape
index

Continuous

-

Locomotion

Maximum
length

Continuous

-

Trophic
position

Vertical use
of the water
column

Categorical

Benthic, benthopelagic, pelagic
and reef

Habitat use
and feeding
strategy

Coastal, neritic and oceanic

Habitat use
and feeding
strategy

Horizontal
Categorical
use of the
water column

3.2.3. Diversity measures and statistical analysis
Fish density for each haul was expressed as the total number of collected
individuals per haul divided by the product of the swept area(GHODRATI SHOJAEI;
AMIN TAGHAVI MOTLAGH, 2011). To analyze and identity patterns in species

28

composition, two approaches were applied. First, a non-metric multidimensional
scaling (NMDS) was performed using the "metaMDS" function (k = 2 dimensions and
100 iterations), based on Jaccard's distance as the dissimilarity measure
(LEGENDRE; LEGENDRE, 2012). This iterative procedure, based on random start
configurations, aimed to achieve a stable global solution for the ordination, as well as
to mitigate the potential influences of different fishing gears applied during sampling.
We also performed a clustering analysis for samples, using the Ward’s method, and
measured the indicator value (IndVal) of species to express species importance in
community classifications (PODANI; CSÁNYI, 2010).
Following the examination of fish assemblages’ composition, the next step was
to analyze the observed patterns in sample aggregation using an analysis of
dissimilarities, which was conducted using the “adonis” function available in the
“vegan” package. This is a robust approach for conducting permutational multivariate
analysis of variance with community ecology data, since dissimilarity patterns among
fish assemblages can be thoroughly investigated while taking into account the
underlying ecological factors that contribute to these variations (ANDERSON;
WALSH, 2013).
Given the variability in size of fishing gear and sampling efforts, Hill numbers were
applied to quantify the different diversity facets (taxonomic and functional) within each
assemblage. The Hill number accounts for both species’ richness and species
abundance, providing a more comprehensive assessment of biodiversity. It offers
several advantages as it is expressed in units of effective numbers of species, allowing
for a more meaningful comparison of diversity across different assemblages in time or
space (CHAO et al., 2014; CHIU; CHAO, 2014). This is particularly valuable when

29

comparing communities with varying levels of rarity and commonness among the
species, such as in this study.
Thus, we employed Taxonomic and Functional Hill numbers, following the
approach outlined by Chiu and Chao (2014), to assess the different components of
diversity (α and β-diversity) of studied assemblages by quantifying the effective
number of equally abundant and functionally equally distinct species (CHIU; CHAO,
2014). Additionally, we incorporated the q factor to account for biomass effects, as
described by (OHLMANN et al., 2019a). The q factor ranges from 0 to 2, where 0
represents species and/or functional richness, 1 represents the exponential Shannon
entropy, and 2 generalizes Rao's quadratic entropy (OHLMANN et al. 2019).
Both taxonomic and functional β-diversity were calculated in a similar manner,
converting the values into dissimilarity indices (β-Hill) that range from 0 (indicating
samples with no shared species or trait composition) to 1 (representing identical
samples). To compare taxonomic and functional diversity measures across regions,
we conducted an analysis of covariance (ANCOVA) after confirming the normality and
homoscedasticity of the data. We then used the “emmeans_test” function from the
“rstatix” package, which performs a post-hoc pairwise comparisons between groups
using the estimated marginal means for fitted models and profiles (KASSAMBARA,
2019).

30

3.3. Results
A total of 97,488 individuals belonging to 209 species were collected during the
study period. Among these, 172 species were distributed throughout the Tropical
Southwestern Atlantic, while 110 species were collected on the Northern Brazil Shelf.
Clustering analysis based on the similarity of assemblage structures (Figure 2)
revealed three distinct species pool among regions, which were subsequently
confirmed by the PERMANOVA analysis (p=0.001).

Figure 2. Multidimensional scaling (nMDS) applied to the similarity matrix of the
collected species illustrating the significant differences in composition between three
identified regions (NBS – Northern Brazil Shelf; TSA-N – North of the Southwestern
Tropical Atlantic; TSA-S – South of the Southwestern Tropical Atlantic).

31

Figure 3. Analysis of similarity in species composition among samples, showing
regional differences throughout the Neotropical Atlantic and the three regions
identified in our study (A – North of the Southwestern Tropical Atlantic; B – Northern
Brazil Shelf; and C – South of the Southwestern Tropical Atlantic).

The first group of species consisted of sampling points distributed along the
Northern Brazil Shelf province (NBS), which were characterized by the presence of
elasmobranchs and larger-sized fish, such as Mustelus canis, Pseudobatos horkelii
and Narcine brasiliensis (see Table S2 for the whole list of species). The second group
represented sampling points located north of the Southwestern Tropical Atlantic
province (TSA-N) that featured many reef-associated species (i.e., Lujanus analis,
Selene vomer, and Chaetodipterus faber), while the third one (TSA-S) comprised

32

sampling points situated in the southern part of this province, mainly comprised for
species predominantly belonging to coastal-estuarine environments, especially
Cathorops agassizii, Larimus breviceps and Sciades herzbergii (Fig. 3).
The regions displayed significant variations in both taxonomic and functional
alpha-diversity (Figure 4 and Table 2). However, the observed patterns were not
congruent. Specifically, while meaningful differences in taxonomic diversity were only
observed between TSA-N and TSA-S (ANCOVA, F= -2.992, p=0.012), it is noteworthy
that TSA-N exhibited lower values of functional diversity even when compared to NBS
(F=2.725, p=0.012), despite the absence of significant variation in species diversity
between the two areas.

Figure 4. Diversity profiles as a function of order q for ordinary Hill numbers (A), and
functional Hill numbers (B), where NBS – Northern Brazil Shelf; TSA-N – North of the
Southwestern Tropical Atlantic; and TSA-S – South of the Southwestern Tropical
Atlantic.

33

Table 2. Estimated marginal means (EMMs) applied as a post-hoc test to detect
significant differences in biodiversity dimensions among identified regions

(NBS –

Northern Brazil Shelf; TSA-N – North of the Southwestern Tropical Atlantic; TSA-S –
South of the Southwestern Tropical Atlantic).
Taxonomic diversity

Functional diversity

Statistic

p-value

Statistic

p-value

NBS × TSA-N

1.919

0.089

2.725

0.012*

NBS × TSA-S

-1.176

0.244

-0.586

0.559

TSA-N × TSA-S

-2.992

0.012*

-3.231

0.006*

Comparison

Examining the similarity in species composition within the study area, the
analysis unveiled a small resemblance among regions (Fig. 5A). However, when
delving into functional composition, we consistently observed higher β-Hill numbers
across all three areas, indicating a significant level of redundancy (Fig. 5B). These
results strongly suggest that multiple species within each region contribute to similar
ecological functions, highlighting a noteworthy degree of functional convergence
within the ecosystems under study.

34

Figure 5. Similarity in species composition (A) and trait composition (B) of fish species
inhabiting coastal muddy bottoms along the Neotropical South Atlantic (NBS –
Northern Brazil Shelf; TSA-N – North of the Southwestern Tropical Atlantic; TSA-S –
South of the Southwestern Tropical Atlantic).

3.4. Discussion
The findings presented in this study unveil the complex nature of coastal muddy
bottoms in tropical regions. The taxonomic structuring shows the existence of distinct
species pools that are dispersed across the study area, giving rise to diverse patterns
across multiple dimensions of fish biodiversity. These patterns go beyond species
richness and abundance, extending to the functional composition of the fish
communities present.
For example, the taxonomic composition of muddy bottoms in the Tropical
South Atlantic exhibited significant differences among studied areas, indicating the
presence of three species pools influenced by regional biogeographic provinces. In
the Northern Brazil Shelf (NBS) province, the influx of continental waters from major
35

rivers such as the Orinoco and the Amazon enriches nutrient inputs, leading to
increased productivity and species diversity (VILAR et al. 2013). These environments
in the NBS coast exhibit high macrofauna density and richness, driven by a wide set
of factors, such as habitat heterogeneity provided by vegetation and the complex local
hydrodynamics, which contribute to the variation in macroinfaunal structure(KNEIB,
1984; RADER, 1984; SANTOS et al., 2020). This diverse community creates a
favorable environment for a wide range of fish species, offering abundant benthonic
food sources and enhancing ecological complexity, especially by the presence of
elasmobranchs Pseudobatos horkelii and Narcine brasiliensis and larger-sized fish,
such as Mustelus canis (CAVALCANTI-LIMA et al., 2023; MAGALHAES; PEREIRA;
DA COSTA, 2015; SANTOS et al., 2020).
On the other hand, the coastline of the northern portion of the Tropical
Southwestern Atlantic (TSA-N) presents a different scenario, as it serves as a
significant transitional zone where the South Equatorial current bifurcates, dividing the
area into two distinct fragments (PEREIRA et al., 2014; PETERSON; STRAMMA,
1991). This division creates a corridor, but also a barrier for the fish fauna (Silva and
Kampel 2022), contributing to significant changes in the diversity of coastal species in
the region, including the presence of a mix set of species that may inhabit different
parts of the TSA-N (GARCIA JÚNIOR; NÓBREGA; OLIVEIRA, 2015).
For instance, many works have shown that while the dynamics of the region,
along with the presence of many coral reef formations enable the presence of reef
species in coastal areas, as seen in our study, these features also prevent the
expansion of other species southwards, which could explain why the area has a
distinct pool of species, and also the lowest values of taxonomic diversity among
regions (FLOETER et al., 2001; JOHANSSON et al., 2013; MOUILLOT et al., 2014b).
36

Another possible explanation for the high incidence of reef species along the coast is
the presence of hypersaline estuaries, which contribute to this pattern of occurrence
(SALES et al., 2018).
In the TSA-S region, local landscape characteristics such as the presence of
mangroves, seagrass, and reef formations may contribute to the structuring of
assemblages and enhance species richness (DA SILVA et al., 2018; DA SILVA;
DOLBETH; FABRÉ, 2021). The southern coast of the Tropical Southwestern Atlantic
is marked by high influx of freshwater and sediments, which results in an estuarinelike condition that extends throughout many habitats along the coast, especially
muddy bottoms (LONGHURST; PAULY, 1987b). This process, known as
"estuarization", brings about significant changes in productivity levels and
environmental factors such as salinity, turbidity, and dissolved oxygen (DA SILVA;
DOLBETH; FABRÉ, 2021; KRUMME; HERBECK; WANG, 2012; PASSOS et al.,
2016b). As a result, these alterations affect the overall structure of the habitats and
have an impact on the composition of fish communities (SALES et al., 2016), allowing
the occurrence of many coastal and estuarine species, as seen in our results.
Differences in species composition and the presence of exclusive species in
each region may also have subsidized the distinct patterns of functional diversity found
within these communities. For instance, in the NBS region, the presence of
elasmobranchs and larger-sized species with higher mobility and trophic levels may
be associated with increases in functional complexity (PAULY; PALOMARES, 2001).
More precisely, elasmobranchs and larger-sized species found within the region might
suggest a complex interplay of trophic interactions and functional diversity. The topdown control exerted by elasmobranchs and the ecological roles fulfilled by largersized species contribute to the functional complexity of the ecosystem (DESBIENS et
37

al., 2021). Through predation and influencing resource availability, these species can
shape the behavior, distribution, and abundance of other organisms within the
community (DESBIENS et al., 2021).
For example, elasmobranch mesopredators, including batoids and small
sharks, play a significant role in structuring the community in coastal marine habitats,
as they may use them as feeding and reproductive areas (DA SILVA et al., 2018;
PETERSON et al., 2001). Their predation on shellfish serves as a crucial link between
apex predators and lower trophic levels, particularly in nearshore sandflats and
seagrass beds(MYERS et al., 2007; VAUDO; HEITHAUS, 2011). Here, we provide
evidence of this role, as species such Mustelus canis, Pseudobatos horkelii and
Narcine brasiliensis enhanced functional diversity in the northern regions of the
Amazon estuary, characterized by extensive muddy habitats resulting from the flow of
the Amazon River. Mustelus canis has been highlighted as a major opportunistic
predator of coastal habitats, feeding on a wide range of prey items and having a
complex foraging ecology (MONTEMARANO; HAVELIN; DRAUD, 2016).
Meanwhile, in the TSA-S region, the collected species predominantly belong to
coastal-estuarine environments, which can be related to the great number of small
estuaries distributed along the whole coast, such as Mugil sp. and Cathorops
agassizii. The species reported herein inhabit marine habitats, but use estuaries
during their life cycle, potentially playing a functional connectivity role between coastal
and neritic environments due to their high mobility (DA SILVA et al., 2022; MACEDO
et al., 2021). In addition, the tropical coastal fish assemblages present in the region
have been strongly associated to increases in functionality of coastal habitats.
Specifically, higher functional diversity (FD) profiles have been reported in shallow

38

areas than in deeper areas, especially during the rainy seasons (MACEDO et al.,
2023, 2021; PASSOS et al., 2016b).
The pulse created by the rainfall favors connectivity and the exchange of
organisms between estuaries and the coast habitats, creating seasonal changes in
temperature, currents, and nutrient input (MACEDO et al., 2023, 2021). The ordered
energy is greater in the rainy season, which means that in this season, an enormous
amount of energy is concentrated in fewer paths than in the dry season, probably, due
to the detritus from the river flow (MACEDO et al. 2023). These patterns align with the
relaxation of niche filtering since deeper areas are located further from the land and
have a much greater volume of water. As a result, they are less abiotically influenced
by seasonal changes in terrestrial precipitation and associated run-off and discharge
(MACEDO et al., 2023; PASSOS et al., 2016b).
On the other hand, in the TSA-N region, the dominance of fish that are
predominantly associated with reef environments may explain why the area has the
lowest values of functional diversity in comparison to the other regions (Sibbing and
Nagelkerke 2000). These fish species have evolved to thrive in highly specialized
ecological niches, presenting a similar set of traits that enhances functional
redundancy, where multiple species perform similar ecological roles or functions within
the ecosystem (NYSTRÖM, 2006). For instance, the body shape of these species has
been linked to their feeding and migratory behaviors, as they primarily reside in
structured environments where movement is characterized more by maneuvering than
high speeds (Reis-Júnior et al., 2023).

39

3.5 . Conclusion
In conclusion, our study elucidates the intricate relationship among environmental
variables, species assemblages, and functional diversity within coastal muddy
bottoms, highlighting their key role as crucial habitats for fish species in coastal
ecosystems. These habitats serve as vital nurseries for many species, while also
playing a fundamental role in supporting complex food webs, which facilitate nutrient
cycling, and sustain fisheries activities.
The highlighted differences in diversity profiles among regions prompts a deeper
investigation into the underlying factors influencing species assembly. It suggests the
presence of unique ecological dynamics or environmental pressures within that may
disproportionately affect the distribution or functional roles of species, thus warranting
further exploration and contextualization. Acknowledging the distinct attributes and
ecological significance of these habitats on a spatial scale is imperative for the
formulation of effective conservation and management strategies, which are essential
for the preservation of fish communities and the enduring maintenance of these areas.

3.6. Acknowledgements
We would like to thank the National Council for Scientific and Technological
Development (CNPq) for funding this research. This study is a contribution from the
projects "Camarão NE_N" (Grant number: 445766/2015-8), which received funding
from the Secretariat of Fisheries and Aquaculture (MAPA/SAP) and the National
Council for Scientific and Technological Development (CNPq), and "Subsidies for the
sustainable management of shrimp fisheries on the northern coast of Paraíba," also
funded by CNPq.
40

3.7. References
AGUILAR-MEDRANO, R.; VEGA-CENDEJAS, M. E. Biogeographical affinities,
trophodynamics, and fisheries pressure in the fish community of the Laguna Madre
Tamaulipas. Journal of Applied Ichthyology, v. 35, n. 4, p. 908–916, 2019.
ANDERSON, M. J.; WALSH, D. C. I. PERMANOVA , ANOSIM , and the Mantel test in
the face of heterogeneous dispersions : What null hypothesis are you testing ? Author
( s ): Marti J . Anderson and Daniel C . I . Walsh Published by : Wiley Stable URL :
http://www.jstor.org/stable/23596913 REF. Ecological Monographs, v. 83, n. 4, p.
557–574, 2013.
BANNAR-MARTIN, K. H. et al. Integrating community assembly and biodiversity to
better understand ecosystem function: the Community Assembly and the Functioning
of Ecosystems (CAFE) approach. Ecology Letters, v. 21, n. 2, p. 167–180, 2018.
BARLETTA, M. The role of salinity in structuring the fish assemblages in a tropical
estuary. Journal of Fish Biology, p. 1–28, 2004.
BRIGGS, J. C.; BOWEN, B. W. A realignment of marine biogeographic provinces with
particular reference to fish distributions. Journal of Biogeography, v. 39, n. 1, p. 12–
30, jan. 2012.
CAPEZZUTO, F. et al. Feeding of the deep-water fish Helicolenus dactylopterus
(Delaroche, 1809) in different habitats: From muddy bottoms to cold-water coral
habitats. Deep Sea Research Part I: Oceanographic Research Papers, v. 159, p.
103252, 2020.
CAVALCANTI-LIMA, L. F. et al. Effects of climate, spatial and hydrological processes
on shaping phytoplankton community structure and β-diversity in an estuary-ocean
continuum (Amazon continental shelf, Brazil). Journal of Sea Research, v. 193, p.
102384, 2023.
CHAO, A. et al. Rarefaction and extrapolation with Hill numbers: a framework for
sampling and estimation in species diversity studies. Ecological monographs, v. 84,
n. 1, p. 45–67, 2014.
41

CHIU, C.-H.; CHAO, A. Distance-based functional diversity measures and their
decomposition: a framework based on Hill numbers. PloS one, v. 9, n. 7, p. e100014,
2014.
DA SILVA, V. et al. Spatial distribution of juvenile fish species in nursery grounds of a
tropical coastal area of the south-western Atlantic. Acta Ichthyologica et Piscatoria,
v. 48, n. 1, p. 9–18, 31 mar. 2018.
DA SILVA, V. E. L. et al. Relative importance of habitat mosaics for fish guilds in the
northeastern coast of Brazil. Regional Studies in Marine Science, v. 50, p. 102145,
2022.
DA SILVA, V. E. L.; DOLBETH, M.; FABRÉ, N. N. Assessing tropical coastal dynamics
across habitats and seasons through different dimensions of fish diversity. Marine
Environmental Research, v. 171, p. 105458, 2021.
DESBIENS, A. A. et al. Revisiting the paradigm of shark-driven trophic cascades in
coral reef ecosystems. Ecology, v. 102, n. 4, p. e03303, 2021.
EKAU, W.; KNOPPERS, B. An introduction to the pelagic system of the North-East
and East Brazilian shelf. Archive of Fishery and Marine Research, v. 47, n. 2–3, p.
113–132, 1999.
FLOETER, S. R. et al. Geographic variation in reef-fish assemblages along the
Brazilian coast. Global Ecology and Biogeography, v. 10, n. 4, p. 423–431, 2001.
FLOETER, S. R. et al. Atlantic reef fish biogeography and evolution. Journal of
Biogeography, v. 35, n. 1, p. 22–47, 2008.
GARCIA JÚNIOR, J.; NÓBREGA, M. F.; OLIVEIRA, J. E. L. Coastal fishes of Rio
Grande do Norte, northeastern Brazil, with new records. Check List, v. 11, n. 3, p.
1659, 17 maio 2015.
GHODRATI SHOJAEI, M.; AMIN TAGHAVI MOTLAGH, S. The Catch Per Unit of
Swept Area (CPUA) and Estimated Biomass of Large Head Hairtail (Trichiurus
lepturus) with an Improved Trawl in the Persian Gulf and Gulf of Oman, Iran. Asian
Fisheries Science, v. 24, p. 209–217, 2011.
42

GOUVEIA, N. DE A. et al. The salinity structure of the Amazon River plume drives
spatiotemporal variation of oceanic primary productivity. Journal of Geophysical
Research: Biogeosciences, v. 124, n. 1, p. 147–165, 2019.
HENRIQUES, S. et al. Biogeographical region and environmental conditions drive
functional traits of estuarine fish assemblages worldwide. Fish and Fisheries, v. 18,
n. 4, p. 752–771, 2017.
IBAÑEZ, A. et al. Unraveling the Mugil curema complex of American coasts integrating
genetic variations and otolith shapes. Estuarine, Coastal and Shelf Science, p.
107914, 2022.
JOHANSSON, C. L. et al. Key herbivores reveal limited functional redundancy on
inshore coral reefs. Coral Reefs, v. 32, p. 963–972, 2013.
KASSAMBARA, A. Practical Statistics in R II. Comparing Groups: Numerical
Variables; Datanovia: Montpellier, France, 2019.
KNEIB, R. T. Patterns of invertebrate distribution and abundance in the intertidal salt
marsh: causes and questions. Estuaries, v. 7, p. 392–412, 1984.
KRUMME, U.; HERBECK, L. S.; WANG, T. Tide-and rainfall-induced variations of
physical and chemical parameters in a mangrove-depleted estuary of East Hainan
(South China Sea). Marine environmental research, v. 82, p. 28–39, 2012.
LEGENDRE, P.; LEGENDRE, L. Numerical ecology. [s.l.] Elsevier, 2012.
LONGHURST, A. R.; PAULY, D. Ecology of tropical oceans. Academic Press, San
Diego, , 1987.
MACEDO, M. et al. Influence of the river flow pulse on the maturity, resilience, and
sustainability of tropical coastal ecosystems. Marine Environmental Research, v.
183, p. 105806, 2023.
MACEDO, M. M. et al. Trophic structure of coastal meta-ecosystems in the tropical
Southwestern Atlantic. Estuarine, Coastal and Shelf Science, v. 263, n. September,
p. 107654, 2021.

43

MAGALHAES, A.; PEREIRA, L. C. C.; DA COSTA, R. M. Relationships between
copepod community structure, rainfall regimes, and hydrological variables in a tropical
mangrove estuary (Amazon coast, Brazil). Helgoland Marine Research, v. 69, p.
123–136, 2015.
MARTINHO, F. et al. The use of nursery areas by juvenile fish in a temperate estuary,
Portugal. Hydrobiologia, v. 587, p. 281–290, 2007.
MCLUSKY, D. S.; ELLIOTT, M. The Estuarine Ecosystem. Cambridge: Oxford
University Press, 2004.
MONTEMARANO, J. J.; HAVELIN, J.; DRAUD, M. Diet composition of the smooth
dogfish (Mustelus canis) in the waters of Long Island, New York, USA. Marine Biology
Research, v. 12, n. 4, p. 435–442, 2016.
MOUILLOT, D. et al. Functional over-redundancy and high functional vulnerability in
global fish faunas on tropical reefs. Proceedings of the National Academy of
Sciences, p. 1–6, 2014.
MYERS, R. A. et al. Cascading effects of the loss of apex predatory sharks from a
coastal ocean. Science, v. 315, n. 5820, p. 1846–1850, 2007.
NETO, J. L. R. et al. Spatio-temporal Variability of Chlorophyll-A in the Coastal Zone
of Northeastern Brazil. Estuaries and Coasts, v. 38, n. 1, p. 72–83, 2014.
NITTROUER, C. A.; DEMASTER, D. J. Sedimentary processes on the Amazon
continental shelf: past, present and future research. Continental Shelf Research, v.
6, n. 1–2, p. 5–30, 1986.
NYSTRÖM, M. Redundancy and Response Diversity of Functional Groups:
Implications for the Resilience of Coral Reefs. AMBIO: A Journal of the Human
Environment, v. 35, n. 1, p. 30–35, fev. 2006.
OHLMANN, M. et al. Diversity indices for ecological networks: a unifying framework
using Hill numbers. Ecology letters, v. 22, n. 4, p. 737–747, 2019.

44

PASSOS, C. V. B. et al. Estuarization increases functional diversity of demersal fish
assemblages in tropical coastal ecosystems. Journal of fish biology, v. 89, n. 1, p.
847–862, 2016.
PAULY, D.; PALOMARES, M. L. D. Fishing Down Marine Food Webs: An Update.
Waters in Peril, v. 279, n. February, p. 47–56, 2001.
PEREIRA, J. et al. The bifurcation of the western boundary current system of the
South Atlantic Ocean. Brazilian Journal of Geophysics, v. 32, n. 2, p. 241–257,
2014.
PETERSON, C. H. et al. Site-specific and density-dependent extinction of prey by
schooling rays: generation of a population sink in top-quality habitat for bay scallops.
Oecologia, v. 129, p. 349–356, 2001.
PETERSON, R. G.; STRAMMA, L. Upper-level circulation in the South Atlantic Ocean.
Progress in oceanography, v. 26, n. 1, p. 1–73, 1991.
PODANI, J.; CSÁNYI, B. Detecting indicator species: Some extensions of the IndVal
measure. Ecological indicators, v. 10, n. 6, p. 1119–1124, 2010.
RADER, D. N. Salt-marsh benthic invertebrates: small-scale patterns of distribution
and abundance. Estuaries, v. 7, p. 413–420, 1984.
SALES, N. DOS S. et al. Do the shallow-water habitats of a hypersaline tropical
estuary act as nursery grounds for fishes? Marine Ecology, v. 39, n. 1, p. e12473,
2018.
SALES, N. S. et al. Dependence of juvenile reef fishes on semi-arid hypersaline
estuary microhabitats as nurseries. Journal of Fish Biology, v. 89, n. 1, p. 661–679,
2016.
SANTOS, T. M. T. et al. Vertical distribution of macrobenthic community of tropical
saltmarshes on the Amazon coast. Regional studies in marine science, v. 40, p.
101536, 2020.

45

SIBBING, F. A.; NAGELKERKE, L. A. J. Resource partitioning by Lake Tana barbs
predicted from fish morphometrics and prey characteristics. Reviews in Fish Biology
and Fisheries, v. 10, n. 4, p. 393–437, 2000.
SILVA, M. et al. Ocean dynamics and topographic upwelling around the Aracati
Seamount - North Brazilian chain from in situ observations and modeling results.
Frontiers in Marine Science, v. 8, n. May, 2021.
SMITH, W. O.; DEMASTER, D. J. Phytoplankton biomass and productivity in the
Amazon River plume: Correlation with seasonal river discharge. Continental Shelf
Research, v. 16, n. 3, p. 291–319, 1996.
SPALDING, M. D. et al. Marine Ecoregions of the World: A Bioregionalization of
Coastal and Shelf Areas. BioScience, v. 57, n. 7, p. 573–583, 2007.
VAUDO, J. J.; HEITHAUS, M. R. Dietary niche overlap in a nearshore elasmobranch
mesopredator community. Marine Ecology Progress Series, v. 425, p. 247–260,
2011.
VILAR, C. C. et al. Local and regional ecological drivers of fish assemblages in
Brazilian estuaries. Marine Ecology Progress Series, v. 485, n. Levin 1992, p. 181–
197, 2013.
WATSON, D. J.; BALON, E. K. Ecomorphological analysis of fish taxocenes in
rainforest streams of northern Borneo. Journal of Fish Biology, v. 25, n. 3, p. 371–
384, 1984.
WIJERMANS, N. et al. Behavioural diversity in fishing—Towards a next generation of
fishery models. Fish and Fisheries, v. 21, n. 5, p. 872–890, 2020.

46

4.CAPÍTULO II: Assessing functional composition patterns in fish communities
along the South-Western Atlantic

Daniele Souto-Vieira1, Victor Emmanuel Lopes da Silva1, Nidia Noemi Fabré1

1

Universidade Federal de Alagoas, Instituto de Ciências Biológicas e da Saúde,

Maceió – Alagoas, Brazil.
Abstract
Describe diversity patterns is an important mechanism to access community ecology,
and functional diversity approach has been a useful tool to understand how
dimensions of biodiversity and ecology interact through the ecosystems. In coastal
ecosystem of South-Western Atlantic, the high diversity of fish and diversification of
environmental and geological condition, could be an interesting area to access the
dimensions of biodiversity through all four completely different provinces. Thus, this
study aims to investigate biogeographic patterns in the species and functional
composition of the South-Western Atlantic. We collected 10113 species of four
provinces from fishbase. Then, we classified them in guilds regarding their feeding
habits, habitat use, energy allocation to growth and reproduction, and used their traits
to obtain a functional space of the communities. Our results showed that temperate
province in the south is less diverse compared to warmer provinces in the north.
Taxonomic similarity was low between faraway provinces, on the other hand functional
similarity and redundancy were high. The proportion of big, generalist and with
maternal care species seems to be higher in the south. In contrast, the north holds
small and specialist group of species. The differences in diversity and life strategies
47

between provinces is a result of different environmental conditions such as river
discharges, habitat complexity and productivity. Also, the niche compression in tropical
habitats, help us to understand diversity of species and food items in the north
provinces.

4.1. Introduction
Biodiversity is an intricate product of evolutionary and ecological processes,
which goes beyond the mere species’ identification and counting in a particular region
(MAZEL et al., 2014). A comprehensive understanding of its patterns requires
considerable attention to a broad spectrum of variables, including the distribution of
species and traits, as well as the underlying processes driving them. For example,
established patterns like the latitudinal biodiversity gradient and Bergmann’s rule have
provided insights into biodiversity dynamics. They indicate a trend of increased
richness and diversity from the poles to the equator and noticeable variations in
organism size, with smaller individuals in warmer climates and larger ones in colder
climates and higher latitudes (BERGMANN, 1847; GASTON, 2000b).
Various mechanisms have been identified as contributors to these patterns,
particularly in tropical regions. A classic example lies in the evolutionary history of
regions characterized by climate stability during glaciations, which facilitated
heightened speciation processes, resulting in greater diversity in the tropics compared
to temperate zones (CARNAVAL; MORITZ, 2008; WALLACE, 1878b). Conversely,
some authors emphasize natural gradients in environmental factors and existing
barriers

as

significant

drivers,

including

temperature,

productivity,

habitat

geomorphology, and ocean currents (LONGHURST, 2010; LONGHURST; PAULY,
48

1987b). For instance, in the marine coastal areas, higher and stable temperatures,
coupled with abundant river inputs in the Tropical South, sustain elevated primary
production levels (LONGHURST; PAULY, 1987b). This, along with the intricate habitat
structures such as mangroves, coral reefs, and seagrass beds, provides diverse
micro-habitats and niches, facilitating species coexistence.(KOSTYLEV et al., 2005;
PIANKA, 2011)
Species interactions, such as competition and predation, further shape species
distribution and influence diversity patterns (MACARTHUR, 1984). Despite this
understanding, knowledge gaps persist, particularly in coastal environments
(HULTGREN et al., 2021; TEICHERT et al., 2018). Fish assemblages in the
Southwestern Atlantic seem to be influenced by dispersal limitations and temperature,
with trait composition being more closely associated with variables related to
connectivity between estuaries and the ocean (HENRIQUES et al., 2017b, 2017a).
However, comprehending how environmental gradients impact trait composition and
functional diversity in coastal environments remains a challenge (MACEDO et al.,
2021).
The Southwestern Atlantic is characterized by its complexity, with varied
environmental conditions and distinct sea geology configurations, resulting in diverse
biogeographic provinces and ecoregions along its coast (SPALDING et al., 2007b).,
Each region's unique characteristics influence biodiversity dimensions differently,
emphasizing the need for a comprehensive approach. This region is home to
numerous species, particularly in coastal systems, making it an important hotspot of
species richness

(VASCONCELOS et al., 2015). Identifying the factors driving

biodiversity dimensions along its length is crucial. Our hypothesis suggests that
environmental and geomorphological gradients shape biodiversity in the South49

western Atlantic. Specific objectives include investigating biogeographic patterns in
species and functional composition and defining latitudinal patterns in parental care.

4.2. Materials and methods
4.2.1. Data acquisition and dataset creation
The study area encompassed four provinces in the South-western Atlantic
according to Spalding (2007) (Figure 1). We selected these provinces based on their
composition and environmental differences. Data on the occurrence of fish species in
the coastal and marine regions of the South-western Atlantic were extracted from
publicly available databases, including ORBIS and GBIF. The data were obtained
using the ‘robis’ and ‘rgbif’ packages for the R statistical software. Initially, the dataset
contained 1147 records, but filtering was conducted to remove duplicates and ensure
the accuracy of taxonomic classification for all identified species. This filtering process
involved removing records with incomplete or inconsistent data, as well as those
flagged as outliers based on their geographic location. The taxonomic classification of
each species was also verified using the most recent taxonomic literature available,
through the ‘rfishbase’ package (BOETTIGER; LANG; WAINWRIGHT, 2012).

50

Figure 1. Study area showing Southwestern Atlantic coast with the provinces
according Spalding et al. (2007). Also, the graphic shows environmental changes
expected along the gradient in the area.

After correcting the database, the ‘letsR’ package was used to create a grid of
1x1 covering the entire study area (VILELA; VILLALOBOS, 2015). A matrix of species
presence and absence was then generated, with each grid containing a binary
representation of the occurrence of each species within. Our main goal was to create
a database that comprises a comprehensive and up-to-date inventory of fish species
occurring in the coastal and marine regions of South-Western Atlantic that would allow
us to carry on a representative analysis of species and trait composition.

51

4.2.2. Functional traits of fish species
Functional traits were selected based on their well-known relationship with
species performance in ecosystems, such as feeding habits, energy allocation to
growth and reproduction, and habitat use (HENRIQUES et al., 2017a). We compiled
a species-trait database with information retrieved from online databases(BEUKHOF
et al., 2019; FROESE; PAULY, 2020) for four functional traits (Table 1). When data
were not available from these sources, we conducted an online search for specific
information and evaluated its reliability based on the reasonableness of reported
values and the apparent credibility of the source. Because removing species with
missing data could bias results for regional species assemblages (BRUM et al., 2017;
NAKAGAWA; FRECKLETON, 2008), whenever information was not available for a
particular species, we used existing data for the closest species in the same genus or
family.

Parental care
Parental care refers to any investment, whether biological or behavioral, made
by parents to ensure reproductive success by increasing the offspring’s chance of
survival (BAYLIS, 1981; GROSS, 2005a). In this study, we employed four categories
as defined by (BALON, 1975) to characterize this life history trait: (a) non-guarders:
these species exhibit no parental care, with external fertilization and zygotes not
tended to by either parent. While this strategy may require less energy from parents,
it often results in higher zygote mortality; (b) guarders: species in this category can
identify and choose suitable spawning sites (such as under rocks, among plants, in
caves, or nests), and the zygotes are cared for by one or both parents; (c) bearers:
52

fish in this group carry their zygotes, typically in the mouth, to protect the offspring and
reduce predation risk; (d) maternal: involves internal fertilization in most species, with
the zygotes carried inside the mother's body.

Salinity tolerance
(a)Freshwater and estuarine - species with low salinity tolerance and that able
to move between freshwater and estuarine habitats; (b) Estuarine and estuarine species are characterized by some tolerance to salinity changes, and depend on
estuaries to complete their life cycle and/or feeding; (c) Estuarine and marine –
species that moves easily between estuaries and marine environment, with tolerance
to salinity change and (d) Marine – species strictly marine and high salinity tolerance.

Trophic guild
Since diet is related with species’ position in the food chain, trophic guilds were
organized bottom up in the following order: detritivores, Herbivorous, planktivorous,
invertivores + herbivorous, invertivores, piscivores + invertivores, piscivores,
piscivores. + Other vertebrates (birds, turtles).

Table 3. Functional traits used to estimate the functional diversity of fish species along
the marine systems of the South-Western Atlantic.
Trait

Ecological meaning

Maximum body

Generally associated with vertical (HENRIQUES et al.,

length (mm)

position in the food web, energy

Reference

2017c)

allocation and life history
53

strategies, dispersal ability and
home range
Salinity tolerance

Physiological ability to deal with
osmotic stress across the

(HENRIQUES et al.,
2017c)

freshwater–marine ecotone
Trophic guild

Role as consumer within the food
web

Parental care

Life history component generally
associated with density-

(HENRIQUES et al.,
2017c)
(LEFCHECK; DUFFY,
2015)

dependent population regulation

4.2.3.Statistical analysis
Taxonomic and Functional Hill numbers were employed to determine β-diversity
following CHIU E CHAO (2014). We assessed species and trait distribution across
each province by calculating the taxonomic and functional diversity of each grid. To
accomplish this, we used the ‘hillR’ package to obtain Hill numbers. Taxonomic and
Functional Hill numbers were used to quantify the effective number of functionally
equally distinct species (CHIU; CHAO, 2014; OHLMANN et al., 2019a) and to assess
abundance effects by weighting species dominance with a q factor (OHLMANN et al.,
2019b). The calculation method for taxonomic and functional β-diversity had converted
values into dissimilarity indices (β-Hill) that ranged from 0 (samples with no shared
species) to 1 (identical samples). Comparisons between taxonomic and functional
diversity measures for all provinces were carried out by an analysis of variance
(ANOVA) since the normality and homoscedasticity of data were met.

54

To better understand patterns of distribution in both dimensions of diversity, we
also calculated equivalent diversity measures for each grid, allowing for spatial
comparisons. The taxonomic diversity component was expressed by the species
richness (SR), which accounted for the total number of species found in each grid.
Functional diversity was evaluated using the dendrogram length functional diversity
(FD) proposed by (PETCHEY; GASTON, 2002), which is a non-abundance weighted
diversity measure that incorporates small functional differences between species and
simultaneously measures diversity at all hierarchical scales. While FD is expected to
be correlated and have a significant relationship with SR, studies have shown that this
relationship is weak at broader scales (ARNAN; CERDÁ; RETANA, 2017). Moreover,
FD covary in different ways along geographic and environmental gradients
(BERNARD-VERDIER et al., 2013; PURSCHKE et al., 2013) , making them suitable
for studies that cross biogeographic regions. Heat maps using the estimated indexes
were created using the “ggplot2” package.

4.3. Results
After correcting and filtering the database, we identified a total of 1,113 fish
species distributed in coastal waters along the latitudinal gradient of the Southwestern
Atlantic. Species richness varied significantly among the four provinces, with the
highest number of species recorded in the Warm Temperate Southwestern Atlantic
(WTSA) province (545 species), followed by the North Brazil Shelf (NBS) with 521
species, the Tropical Southwestern Atlantic (TSA) with 496 species, and the
Magellanic (MAG) province with 143 species.

55

In terms of taxonomic composition, distinct patterns were identified, with the
distance between provinces playing a significant role in estimating dissimilarity (Figure
2). In contrast, for the functional dimension, a pattern of redundancy was observed
(Figure 2).

Figure 2. Similarity in taxonomic composition (A) and trait composition (B) of fish
species among the four provinces along the latitudinal gradient of Southwestern
Atlantic coastal waters.

Across all provinces, trends in fish traits unfolded systematically, reflecting
variations in size, habitat use, parental care, and diet. Towards the northern regions,
there was an increasing prevalence of small and medium-sized species, coupled with
a greater diversity of habitat use guilds compared to the south (Figure 3). In addition,
a broader array of feeding habits was also observed for the norther regions, resulting
in a more complex dietary composition and a richer tapestry of trophic guilds and
occupied niches. Conversely, in the southern reaches, larger and extra-large fishes
were more common, suggesting a shift towards habitats conducive to their size and
foraging behaviors. While most species across all provinces did not exhibit parental
56

care behaviors, there was a notable increase in maternal care observed in the
Magellanic province, particularly emblematic of southern regions.

Figure 3. Proportions of traits represented in fish assemblages of coastal waters of
four provinces in the Southwest Altantic..For maximum body length – S= small, M=
medium, L= large, and XL = extra large; for habitat – F&E= fresh water and marine
species; E= estuarine, E&M= estuarine and marine, M= marine; for parental care B=
bearers, G= guarders, Mt= maternal care, N= no parental care; for diet – De= detritus,
Al= algae, Pl= plankton, In= invertebrates, I&F= invertebrates and fish, Om=
Invertebrates and plants, Ca= only fish, Pi= fish and other vertebrates (birds and
turtles).

4.4 Discussion
Our study sheds light on the dimensions of fish diversity across the provinces
of the Southwestern Atlantic. As expected, species richness exhibited a latitudinal
gradient, with higher richness observed in tropical provinces, gradually decreasing
towards the south. The similarity of fish communities and their diversity correlated with
57

the proximity of provinces, with closer provinces sharing more species compared to
those more distantly located. However, functional patterns were less predictable.
While overall metrics of functional diversity indicated a redundancy pattern among
regions, a closer examination of trait distribution revealed intriguing gradients in trait
distribution across the study area.
In the North Brazil Shelf province, the pronounced diversity index and richness
of species align with the latitudinal pattern of biodiversity (GASTON, 2000b). The
region's biogeographical history, characterized by significant freshwater discharge
from rivers such as the Orinoco and Amazonas, creates barriers to coastal dispersal
for certain fish species (FLOETER et al., 2008c; ROCHA, 2003). This phenomenon
likely contributes to regional patterns of endemism. Additionally, the presence of coral
reefs along the coast, coupled with high productivity and habitat complexity, fosters
greater species diversity in the area (ROCHA, 2003).
Conversely, in the Magellanic province, lower species diversity and limited
species distributions along the coast may be influenced by variations in salinity and
temperature. The region receives subantarctic water from the Antarctic convergence
and discharges from ice melt originating from Tierra del Fuego, the Strait of Magellan,
and rivers of Santa Cruz (COUSSEAU et al., 2020). Such factors lead to spatial
variations in salinity, with coastal environments exhibiting lower tolerance to salinity
changes compared to the open sea under the influence of the Falkland Current
(BALECH; EHRLICH, 2008). Species occurrence in this region is contingent upon their
ability to tolerate low temperatures and temporal and spatial fluctuations in salinity.
Provinces in close geographical proximity with similar environmental conditions
are more likely to share similar species compositions (CHASE, 2003). For instance,
the warm climate and presence of coral reefs in the North Brazil Shelf and Tropical
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Southwestern Atlantic provinces contribute to the observed similarity in species
composition. Coral reefs serve as specialized habitats for many marine species,
particularly reef-associated fish, creating a common ecological niche and selecting for
species adapted to coral reef environments.
The functional redundancy observed between provinces is consistent with
previous studies on estuarine and reef fishes (BENDER et al., 2017; HENRIQUES et
al., 2017d; MOUILLOT et al., 2014b). Tropical fish communities typically exhibit
functional redundancy, with certain functional groups harboring a greater number of
species due to phylogenetic trait conservatism. This redundancy enhances ecosystem
functioning, stability, and resilience in the face of environmental change. However, rare
species with unique functional trait configurations may play critical roles in ecosystem
functions and may be particularly vulnerable to climate change (DA SILVA; FABRÉ,
2019).
In biogeographic regions exhibiting a pattern of redundancy, trait distributions
tend to be homogeneous, characterized by two main combinations: large-bodied
species with piscivorous diets and small-bodied species with omnivorous diets
(BENDER et al., 2017). This pattern aligns with our findings and can explain the high
proportion of small species with diverse feeding habits in the North Brazil Shelf
province and the prevalence of large-bodied species feeding on fish and invertebrates
in the Magellanic province. However, it is essential to recognize that trait distributions
may be influenced by various ecological and environmental factors specific to each
region, including temperature, salinity, and precipitation (HENRIQUES et al., 2017d).
Therefore, it is important to take in consideration differences in trait distribution, even
when faced with an apparent redundant patter.

59

For example, the Magellanic province exhibited a clear tendency towards larger
body sizes, in line with Bergmann's rule, which suggests that organisms in colder
environments tend to have larger body sizes. This may be attributed to metabolic
efficiency in use and energy storage capabilities in cold environments, facilitating the
success of large-bodied species such as pelagic species and sharks (DICKERSON,
1978; WALKER, 2005). Since energetic condition is what control parental investment
in reproductive events (COOKE et al., 2006), larger body sizes in cold habitats may
be associated with parental care strategies, as larger bodies individuals tend to have
higher metabolic and lower fecundity rates, necessitating investment in parental care
to ensure offspring survival (CARRIER; PRATT; CASTRO, 2004). Therefore, internal
fertilization and maternal care are common strategies observed in the Magellanic
province to safeguard offspring survival. Conversely, species in tropical provinces tend
to be smaller and mature earlier (DICKERSON, 1978), which is associated with their
lower metabolic rates (ALONSO-ALVAREZ; VELANDO, 2012; COOKE et al., 2006).
Because of that, parental care seems to be energetically expensive to small body
species, and they use other strategies to protect their brood such as small egg size,
nesting and guarding behavior (COOKE et al., 2006; GROSS, 2005b; ZIĘBA et al.,
2018).
In conclusion, our study reveals intricate patterns of fish diversity across the
Southwestern Atlantic provinces. While we confirm the expected latitudinal gradient in
species richness, we uncover nuanced variations in functional patterns. Factors such
as freshwater discharge and habitat complexity drive biodiversity in certain provinces,
while environmental gradients like salinity and temperature shape species
distributions elsewhere. Proximity and environmental similarity facilitate species
sharing among neighboring provinces, but the observed functional redundancy
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underscores the importance of considering trait distributions. Our findings underscore
the need for a holistic understanding of ecological processes to inform effective
conservation strategies amidst environmental change. Future research should focus
on elucidating the mechanisms driving trait distributions and their implications for
ecosystem resilience, while integrating climate change projections to anticipate and
mitigate impacts on Southwestern Atlantic biodiversity.

4.5. References
ALONSO-ALVAREZ, C.; VELANDO, A. Benefits and costs of parental care. Em: The
Evolution of Parental Care. [s.l.] Oxford University Press, 2012. p. 40–61.
ARNAN, X.; CERDÁ, X.; RETANA, J. Relationships among taxonomic, functional, and
phylogenetic ant diversity across the biogeographic regions of Europe. Ecography, v.
40, n. 3, p. 448–457, 2017.
BALECH, E.; EHRLICH, M. D. Esquema biogeográfico del mar Argentino. 2008.
BALON, E. K. Reproductive guilds of fishes: a proposal and definition. Journal of the
Fisheries Board of Canada, v. 32, n. 6, p. 821–864, 1975.
BAYLIS, J. R. The evolution of parental care in fishes, with reference to Darwin’s
rule of male sexual selectionEnv. Biol. Fish. [s.l: s.n.].
BENDER, M. G. et al. Isolation drives taxonomic and functional nestedness in tropical
reef fish faunas. Ecography, v. 40, n. 3, p. 425–435, 2017.
BERGMANN, C. Uber die Verhaltnisse der warmeokonomie der Thiere zu uber
Grosso. Gottinger studien, v. 3, p. 595–708, 1847.

61

BERNARD-VERDIER, M. et al. Partitioning phylogenetic and functional diversity into
alpha and beta components along an environmental gradient in a M editerranean
rangeland. Journal of Vegetation Science, v. 24, n. 5, p. 877–889, 2013.
BEUKHOF, E. et al. A trait collection of marine fish species from North Atlantic and
Northeast Pacific continental shelf seas. Pangaea, v. 1, p. 12, 2019.
BOETTIGER, C.; LANG, D. T.; WAINWRIGHT, P. C. rfishbase: exploring, manipulating
and visualizing FishBase data from R. Journal of Fish Biology, v. 81, n. 6, p. 2030–
2039, 2012.
BRUM, F. T. et al. Global priorities for conservation across multiple dimensions of
mammalian diversity. Proceedings of the National Academy of Sciences of the
United States of America, v. 114, n. 29, p. 7641–7646, 2017.
CARNAVAL, A. C.; MORITZ, C. Historical climate modelling predicts patterns of
current biodiversity in the Brazilian Atlantic forest. Journal of Biogeography, v. 35, n.
7, p. 1187–1201, jul. 2008.
CARRIER, J. C.; PRATT, H. L.; CASTRO, J. I. Reproductive biology of elasmobranchs.
Biology of sharks and their relatives, v. 10, p. 269–286, 2004.
CHASE, J. M. Community assembly: When should history matter? Oecologia, v. 136,
n. 4, p. 489–498, 2003.
CHIU, C.-H.; CHAO, A. Distance-based functional diversity measures and their
decomposition: a framework based on Hill numbers. PloS one, v. 9, n. 7, p. e100014,
2014.
COOKE, S. J. et al. Energetics of parental care in six syntopic centrarchid fishes.
Oecologia, v. 148, n. 2, p. 235–249, jun. 2006.
COUSSEAU, M. B. et al. The Magellanic Province and its fish fauna (South America):
Several provinces or one? Journal of Biogeography, v. 47, n. 1, p. 220–234, 2020.
DA SILVA, V. E. L.; FABRÉ, N. N. Rare Species Enhance Niche Differentiation Among
Tropical Estuarine Fish Species. Estuaries and Coasts, v. 42, n. 3, p. 890–899, 2019.
62

DICKERSON, G. E. Animal size and efficiency: basic concepts. Animal Science, v.
27, n. 3, p. 367–379, 2 dez. 1978.
FLOETER, S. R. et al. Atlantic reef fish biogeography and evolution. Journal of
Biogeography, v. 35, n. 1, p. 22–47, jan. 2008.
GASTON, K. J. Global patterns in biodiversity. Nature, v. 405, n. 6783, p. 220–7, 2000.
GROSS, M. R. The evolution of parental care. Quarterly Review of Biology. Anais,
2005.
HENRIQUES, S. et al. Processes underpinning fish species composition patterns in
estuarine ecosystems worldwide. Journal of Biogeography, v. 44, n. 3, p. 627–639,
2017a.
HENRIQUES, S. et al. Biogeographical region and environmental conditions drive
functional traits of estuarine fish assemblages worldwide. Fish and Fisheries, v. 18,
n. 4, p. 752–771, 2017b.
HULTGREN, K. M. et al. Crustacean diversity in the Puget Sound: Reconciling
species, phylogenetic, and functional diversity. Marine Biodiversity, v. 51, n. 2, p. 37,
2021.
KOSTYLEV, V. E. et al. The relative importance of habitat complexity and surface area
in assessing biodiversity: Fractal application on rocky shores. Ecological
Complexity, v. 2, n. 3, p. 272–286, set. 2005.
LEFCHECK, J. S.; DUFFY, J. E. Multitrophic functional diversity predicts ecosystem
functioning in experimental assemblages of estuarine consumers. Ecology, v. 96, n.
11, p. 2973–2983, 2015.
LONGHURST, A. R. Ecological Geography of the Sea. 2. ed. [s.l.] Elsevier, 2010.
LONGHURST, A. R.; PAULY, D. Ecology of tropical oceans. Academic Press, San
Diego, , 1987.
MACARTHUR, R. H. Geographical Ecology: Patterns in the Distribution of
Species. [s.l.] Princeton University Press, 1984.
63

MACEDO, M. M. et al. Trophic structure of coastal meta-ecosystems in the tropical
Southwestern Atlantic. Estuarine, Coastal and Shelf Science, v. 263, n. September,
p. 107654, 2021.
MAZEL, F. et al. Multifaceted diversity–area relationships reveal global hotspots of
mammalian species, trait and lineage diversity. Global ecology and biogeography,
v. 23, n. 8, p. 836–847, 2014.
MOUILLOT, D. et al. Functional over-redundancy and high functional vulnerability in
global fish faunas on tropical reefs. Proceedings of the National Academy of
Sciences, p. 1–6, 2014.
NAKAGAWA, S.; FRECKLETON, R. P. Missing inaction: the dangers of ignoring
missing data. Trends in ecology & evolution, v. 23, n. 11, p. 592–596, 2008.
OHLMANN, M. et al. Diversity indices for ecological networks: a unifying framework
using Hill numbers. Ecology letters, v. 22, n. 4, p. 737–747, 2019.
PETCHEY, O. L.; GASTON, K. J. Functional diversity (FD), species richness and
community composition. Ecology Letters, v. 5, n. 3, p. 402–411, maio 2002.
PIANKA, E. R. Evolutionary ecology: Eric R. Pianka (Original work published 1974),
2011.
PURSCHKE, O. et al. Contrasting changes in taxonomic, phylogenetic and functional
diversity during a long-term succession: insights into assembly processes. Journal of
Ecology, v. 101, n. 4, p. 857–866, 2013.
ROCHA, L. A. Patterns of distribution and processes of speciation in Brazilian reef
fishes. Journal of Biogeography, v. 30, n. 8, p. 1161–1171, 2003.
SPALDING, M. D. et al. Marine Ecoregions of the World: A Bioregionalization of
Coastal and Shelf Areas. BioScience, v. 57, n. 7, p. 573–583, 2007.
TEICHERT, N. et al. Environmental drivers of taxonomic, functional and phylogenetic
diversity (alpha, beta and gamma components) in estuarine fish communities. Journal
of Biogeography, v. 45, n. 2, p. 406–417, fev. 2018.
64

VASCONCELOS, R. P. et al. Global patterns and predictors of fish species richness
in estuaries. Journal of Animal Ecology, v. 84, n. 5, p. 1331–1341, 2015.
VILELA, B.; VILLALOBOS, F. LetsR: A new R package for data handling and analysis
in macroecology. Methods in Ecology and Evolution, v. 6, n. 10, p. 1229–1234, 1
out. 2015.
WALKER, T. I. Reproduction in fisheries science. In ‘Reproductive Biology and
Phylogeny of Chondrichthyes: Sharks, Batoids and Chimaeras’.(Ed. WC Hamlett.) pp.
81–127. Science Publishers, 2005.
WALLACE, A. R. Tropical nature, and other essays. Macmillan and Company, 1878.
ZIĘBA, G. et al. Parental care compromises feeding in the pumpkinseed (Lepomis
gibbosus). Science of Nature, v. 105, n. 3–4, 2018.

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6. CONCLUSÃO
Em resumo, as comunidades de peixes do Atlântico Sul são fundamentais para
a manutenção dos ecossistemas marinhos costeiros, e são influenciadas por diversos
fatores bióticos e abióticos que afetam a distribuição e a abundância das espécies.
Especialmente nos habitats considerados como berçário de diversas espécies de
peixes, há uma forte correlação entre fatores ambientais, composição de espécies e
diversidade funcional. Assim, os processos locais como salinização e estuarização
ajudam a explicar a diversidade taxonômica e funcional em ambientes costeiros de
fundos de lama.
Além disso, observamos um gradiente latitudinal já esperado na riqueza de
espécies. Esse padrão de distribuição das espécies é resultado da influência de
fatores como descarga de água doce e complexidade do habitat impulsionam a
biodiversidade em certas províncias, enquanto gradientes ambientais como
salinidade e temperatura influenciam outras comunidades.
No geral foi observado uma redundância funcional consistente tanto na escala
local quanto na regional, a composição taxonômica e funcional são distintas,
reforçando a importância de do pool de espécies locais para a manutenção da
biodiversidade, na estabilidade das cadeias alimentares. Ademais, o funcionamento
compreensão da estrutura funcional dessas comunidades é essencial para
desenvolver estratégias de gestão sustentável dos recursos pesqueiros e para a
conservação eficaz dos ecossistemas costeiros no Atlantico Sul.

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