Mapping seahorses in a Brazilian estuary: mangrove structures as key predictors for distribution and habitat preference

PeerJ. 2023 Jul 20:11:e15730. doi: 10.7717/peerj.15730. eCollection 2023.

Abstract

Planning for effective conservation demands an accurate understanding of the ecological aspects of species, particularly their distribution and habitat preferences. This is even more critical in the case of data-poor, rare, and threatened species, such as seahorses, mainly when they inhabit vulnerable ecosystems like estuaries. Given the importance of better understanding these parameters to design seahorse conservation strategies, we mapped the distribution and assessed habitat preferences of longsnout seahorses (Hippocampus reidi) in a mangrove estuary in a Brazilian protected area. Using generalised linear mixed-effects models we found that dense mangrove cover macro-habitats and shallow depths predicted seahorse sightings and higher densities. Furthermore, the selective index of micro-habitats used by seahorses showed that seahorses exhibited a preference for mangrove structures as holdfasts (i.e., fallen branches). Due to the significant importance of mangroves in providing suitable habitats for H. reidi in estuaries, it is crucial to enforce the protection of these ecosystems in conservation and management strategies for the species.

Keywords: Conservation; Hippocampus reidi; Longsnout seahorse; Mangrove; Syngnathids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brazil
  • Ecosystem*
  • Endangered Species
  • Estuaries
  • Smegmamorpha*

Grants and funding

This work was supported by the German cooperation for sustainable development through Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH. Rômulo Romeu Nóbrega Alves received a National Council for Scientific and Technological Development (CNPq) productivity research grant. Anna Karolina Martins Borges received a Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Brasil (CAPES) scholarship (88887.633844/2021-00). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.