Resource partitioning between fisheries and endangered sharks in a tropical marine food web

Author(s)

Marquez-Velasquez, Viviana ^{[1, 2, 3]} ; Navia, Andres F. ^{[2, 4]} ; Rosa, Ricardo S. ^[5] ; Guimaraes Jr, Paulo R. ; Raimundo, Rafael L. G. ^{[6, 7, 8, 9]}

Affiliation

^[1] Univ Fed Paraiba, Programa Posgrad Ciencias Biol Zool, BR-58051900 Joao Pessoa, Paraiba - Brazil

^[2] Fdn Colombiana Invest & Conservac Tiburones & Ray, SQUALUS, Calle 10a 72-35, Apto 310E, Cali - Colombia

^[3] Univ Fed Paraiba, Lab Anim Ecol, IRIS Res Grp, Innovat Resilience Inclus & Sustainabil, Campus 4, BR-58297000 Rio Tinto, PB - Brazil

^[4] Univ Valle, Dept Biol, Grp Invest Ecol Anim, Cali 25360 - Colombia

^[5] Univ Fed Paraiba, Ctr Ciencias Exatas & Nat, Dept Sistemat & Ecol, BR-58051900 Joao Pessoa, Paraiba - Brazil

^[6] Guimaraes Jr, Jr., Paulo R., Univ Fed Paraiba, Lab Anim Ecol, IRIS Res Grp, Innovat Resilience Inclus & Sustainabil, Campus 4, BR-58297000 Rio Tinto, PB - Brazil

^[7] Dept Engn & Meio Ambiente, BR-58297000 Rio Tinto, PB - Brazil

^[8] Programa Posgrad Ecol & Monitoramento Ambiental P, BR-58297000 Rio Tinto, PB - Brazil

^[9] Univ Fed Paraiba, Programa Posgrad Ecol & Monitoramento Ambiental P, Campus 4, BR-58297000 Rio Tinto, PB - Brazil

• Document type: Journal article
• Source: ICES JOURNAL OF MARINE SCIENCE; v. 78, n. 7, p. 2518-2527, OCT 2021.
• Web of Science Citations: 0

Abstract

Fisheries can act as top predators and affect marine biodiversity and ecosystem functioning via their target species. We studied a coastal food web in the Pacific Ocean that is modular and encompasses 360 species and small- and large- scale fisheries. Small- scale fisheries (SSF), two hammerhead sharks, one stingray, and one flatfish species are network hubs, interacting with multiple species among and within trophic levels (TLs) and modules. SSF and endangered hammerhead sharksact as hyper-hubs, which are network hubs preying on other network hubs and likely imposing widespread top-down effects. Hyper-hubs have two consequences to network structure. First, they show low dietary overlap, connecting the network in complementary ways. Second, they have overlapping indirect interactions, suggesting they can strongly affect each other. Simulations assuming distinct fishery regulations and species extinctions of different Tls and topological roles did not change network structure but redefined hub identity. We hypothesize that competition shapes resource partitioning between fisheries and hammerhead sharks. Our findings suggest that ecosystem-level strategies informed by network approaches can optimize investments to conserve marine ecosystems and ensure food security over coastal areas in the developing world. (AU)

• FAPESP's process: 18/14809-0 - Evolutionary dynamics in ecological networks
• Grantee: Paulo Roberto Guimarães Junior
• Support Opportunities: Research Grants - Young Investigators Grants - Phase 2