Diet of the bonnethead (Sphyrna tiburo) along the northern Gulf of Mexico and southeastern Atlantic coast of the United States

Date

2022-07-14

Authors

Branham, C. C.
Frazier, Bryan
Strange, J. B.
Galloway, Ashley
Adams, Douglas
Drymon, James Marcus
Grubbs, Ralph
Portnoy, David
wells, robert
Sancho, Gorka

Journal Title

Journal ISSN

Volume Title

Publisher

Abstract

Diet of the bonnethead (Sphyrna tiburo) along the northern Gulf of Mexico and southeastern Atlantic coast of the United States. The diet of a potentially omnivorous coastal shark species, the bonnethead (Sphyrna tiburo), was examined in the western Atlantic along the coast of the southeastern United States. A total of 423 stomachs collected from Texas, Alabama, Florida and South Carolina were analyzed using standardized stomach content analysis methods. The diet was dominated by crabs, primarily portunids (Callinectes spp.), across the geographical range analyzed, though the relative importance of crabs varied between regions. Ontogenetic shifts in diet were not observed throughout the region studied. Female and male bonnetheads in South Carolina displayed different diets, particularly in the amount of portunid crabs consumed, with a higher proportion ingested by females. Bonnetheads consumed limited amounts of seagrasses in all regions except in South Carolina, where they occupy habitats without seagrasses in marsh dominated bays and estuaries. This finding indicates that, at least seasonally, seagrasses are not an essential part of the diet of this shark species and may only occur in stomachs as accidental ingestion.

Description

Keywords

elasmobranch diet, feeding ecology, sphyrna tiburo, callinectes spp., seagrasses

Sponsorship

Funding for the FSU surveys was from the NOAA SEFSC as part of the GulfSPAN program. This study was funded by Summer Undergraduate Research Funds from the College of Charleston and the School of Science and Mathematics, and by NOAA/NMFS Saltonstall–Kennedy funds (NA16NMF4270225).This is contribution 857 of the South Carolina Marine Resources Division.

Rights:

Attribution 4.0 International

Citation

Branham, C. C., Frazier, B. S., Strange, J. B., Galloway, A. S., Adams, D. H., Drymon, J. M., Grubbs, R. D., Portnoy, D. S., Wells, R. J. D., Sancho, G., 2022. Diet of the bonnethead (Sphyrna tiburo) along the northern Gulf of Mexico and southeastern Atlantic coast of the United States. Animal Biodiversity and Conservation, 45: 257-267, DOI: https://doi.org/10.32800/abc.2022.45.0257