Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters
Abstract Rock hind ( Epinephelus adscensionis ) and spotted moray ( Gymnothorax moringa ) are ubiquitous mesopredators that co‐occur in the nearshore waters of Ascension Island in the South Atlantic Ocean, where they have significant cultural and subsistence value, but management of their non‐commer...
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Online Access: | http://dx.doi.org/10.1111/jfb.15744 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15744 |
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crwiley:10.1111/jfb.15744 2024-05-19T07:48:34+00:00 Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters Orrell, Danielle L. Sadd, Daniel Jones, Kirsty L. Chadwick, Kate Simpson, Tiffany Philpott, Darcy E. Hussey, Nigel E. Natural Sciences and Engineering Research Council of Canada 2024 http://dx.doi.org/10.1111/jfb.15744 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15744 en eng Wiley http://creativecommons.org/licenses/by-nc/4.0/ Journal of Fish Biology ISSN 0022-1112 1095-8649 Aquatic Science Ecology, Evolution, Behavior and Systematics journal-article 2024 crwiley https://doi.org/10.1111/jfb.15744 2024-04-22T07:34:59Z Abstract Rock hind ( Epinephelus adscensionis ) and spotted moray ( Gymnothorax moringa ) are ubiquitous mesopredators that co‐occur in the nearshore waters of Ascension Island in the South Atlantic Ocean, where they have significant cultural and subsistence value, but management of their non‐commercial take is limited. This isolated volcanic system is home to high biomass and low species diversity, which poses two key questions: How can two mesopredators that perform similar ecological roles coexist? And if these two species are so ecologically similar, can they be managed using the same approach? Here, we combined acoustic telemetry, stomach content analysis, and stable isotope analysis to (i) explore space use and diet choices within and between these two species and (ii) to assess appropriate species‐specific management options. Although rock hind had high residency and small calculated home ranges (0.0001–0.3114 km 2 ), spotted moray exhibited shorter periods of residency (<3 months) before exiting the array. Vertical space use differed significantly across the 20‐month tracking period, with individual differences in vertical space observed for both species. A hierarchical generalized additive model using 12‐h averaged depth data identified that rock hind occurred lower in the water column than spotted moray, with both species occupying moderately deeper depths at night versus day (+1.6% relative depth). Spotted moray depth was also significantly predicted by lunar illumination. Aggregating samples by species and tissue type, Bayesian ecological niche modeling identified a 53.14%–54.15% and 78.02%–97.08% probability of niche overlap from fin clip and white muscle, respectively, whereas limited stomach content data indicated a preference for piscivorous prey. Variability in niche breadth between years suggests these species may exploit a range of prey items over time. These findings indicate that although these two species perform a similar ecological role by feeding on prey occupying the same trophic ... Article in Journal/Newspaper South Atlantic Ocean Wiley Online Library Journal of Fish Biology |
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Open Polar |
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Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
topic |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Aquatic Science Ecology, Evolution, Behavior and Systematics Orrell, Danielle L. Sadd, Daniel Jones, Kirsty L. Chadwick, Kate Simpson, Tiffany Philpott, Darcy E. Hussey, Nigel E. Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
topic_facet |
Aquatic Science Ecology, Evolution, Behavior and Systematics |
description |
Abstract Rock hind ( Epinephelus adscensionis ) and spotted moray ( Gymnothorax moringa ) are ubiquitous mesopredators that co‐occur in the nearshore waters of Ascension Island in the South Atlantic Ocean, where they have significant cultural and subsistence value, but management of their non‐commercial take is limited. This isolated volcanic system is home to high biomass and low species diversity, which poses two key questions: How can two mesopredators that perform similar ecological roles coexist? And if these two species are so ecologically similar, can they be managed using the same approach? Here, we combined acoustic telemetry, stomach content analysis, and stable isotope analysis to (i) explore space use and diet choices within and between these two species and (ii) to assess appropriate species‐specific management options. Although rock hind had high residency and small calculated home ranges (0.0001–0.3114 km 2 ), spotted moray exhibited shorter periods of residency (<3 months) before exiting the array. Vertical space use differed significantly across the 20‐month tracking period, with individual differences in vertical space observed for both species. A hierarchical generalized additive model using 12‐h averaged depth data identified that rock hind occurred lower in the water column than spotted moray, with both species occupying moderately deeper depths at night versus day (+1.6% relative depth). Spotted moray depth was also significantly predicted by lunar illumination. Aggregating samples by species and tissue type, Bayesian ecological niche modeling identified a 53.14%–54.15% and 78.02%–97.08% probability of niche overlap from fin clip and white muscle, respectively, whereas limited stomach content data indicated a preference for piscivorous prey. Variability in niche breadth between years suggests these species may exploit a range of prey items over time. These findings indicate that although these two species perform a similar ecological role by feeding on prey occupying the same trophic ... |
author2 |
Natural Sciences and Engineering Research Council of Canada |
format |
Article in Journal/Newspaper |
author |
Orrell, Danielle L. Sadd, Daniel Jones, Kirsty L. Chadwick, Kate Simpson, Tiffany Philpott, Darcy E. Hussey, Nigel E. |
author_facet |
Orrell, Danielle L. Sadd, Daniel Jones, Kirsty L. Chadwick, Kate Simpson, Tiffany Philpott, Darcy E. Hussey, Nigel E. |
author_sort |
Orrell, Danielle L. |
title |
Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
title_short |
Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
title_full |
Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
title_fullStr |
Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
title_full_unstemmed |
Coexistence, resource partitioning, and fisheries management: A tale of two mesopredators in equatorial waters |
title_sort |
coexistence, resource partitioning, and fisheries management: a tale of two mesopredators in equatorial waters |
publisher |
Wiley |
publishDate |
2024 |
url |
http://dx.doi.org/10.1111/jfb.15744 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfb.15744 |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
Journal of Fish Biology ISSN 0022-1112 1095-8649 |
op_rights |
http://creativecommons.org/licenses/by-nc/4.0/ |
op_doi |
https://doi.org/10.1111/jfb.15744 |
container_title |
Journal of Fish Biology |
_version_ |
1799466863550267392 |