Where the grass is greenest in seagrass seascapes depends on life history and simple species traits of fish

Tropical seagrass meadows are critical habitats for many fish species, yet few studies have investigated the influence of multiple scale-dependent factors and marine protected areas on seagrass fish species of differing life histories. We assessed the influence of fine-scale seagrass meadow characteristics and seascape-scale variables on the abundance of fish in a seagrass-dominated seascape in the Bazaruto Archipelago, Mozambique, particularly examining patterns of nursery- vs. resident species as well as mobile- vs. sedentary species. We found that fish distribution patterns in this seagrass-dominated seascape were dependent on species’ life history characteristics; nursery taxa showed lower abundance in seagrass meadows further from adult reef habitats, while resident species within seagrass meadows occurred in higher abundances far from reefs. For taxa utilizing both mangroves and seagrass meadows as nursery habitat, proximity to mangroves was an important factor. Fish abundances were generally influenced by variables at the seascape scale (km), while sedentary species were predominantly influenced by area variables, and smaller seascapes (<500 m in radius) better explained distribution patterns. The influence of marine protected areas was taxon-specific, with the strongest effects of protection on resident species. Our results indicate that protection efforts in seagrass-dominated seascapes can have varying impacts on fish distribution, depending on the life history of the species present, and the geographical placement of the reserve within the seascape. Further, we suggest that simple species attributes can be utilised to describe generalized abundance patterns of fish in seagrass seascapes.

Description

Acknowledgements : We thank M. Ambly, C. d’Agata and A. Ostman ¨ for help in the field. We also wish to thank the VCWS and the Parque Nacional de Arquipélago de Bazaruto (PNAB) for their thorough support during the field work, Mr. H. Brown and all the staff at Msasa, G. van Wyk and our skipper Orlando. We also thank three anonymous reviewers whose comments helped improve the manuscript. Research permits – Permission to conduct research in the PNAB was provided by the Administraçao ˜ Nacional das Áreas de Conservação (ANAC). Research permission for the Santuario Bravio de Vilanculos (Vilanculos Wildlife Coastal Sanctuary - VWCS) was provided by the VWCS. Funding was provided by the Western Indian Ocean Marine Science Association (WIOMSA) MARG I grant, Stockholm University (Sweden) and the Swedish Research Council (VR; no. E0344801 and 2015–05902).

Keywords

Seagrass Reef fish Seascape ecology Boosted regression trees Nursery habitat Marine protected areas

URI

http://hdl.handle.net/10400.8/7528

Citation

Linda Eggertsen, Whitney Goodell, Cesar A.M.M. Cordeiro, Damboia Cossa, Marcos de Lucena, Charlotte Berkström, João N. Franco, Carlos E.L. Ferreira, Salomão Bandeira, Martin Gullström, Where the grass is greenest in seagrass seascapes depends on life history and simple species traits of fish, Estuarine, Coastal and Shelf Science, Volume 266, 2022, 107738, ISSN 0272-7714, https://doi.org/10.1016/j.ecss.2021.107738.