A Stingray’s Preferred Menu: A Wide Selection of Small Invertebrates
Location
HCAS Guy Harvey Oceanographic Center, Nova Southeastern University
Start
2-14-2025 10:00 AM
End
2-14-2025 10:15 AM
Type of Presentation
Oral Presentation
Abstract
The Indian River Lagoon (IRL) is a brackish estuarine ecosystem along the Atlantic coast of Florida. Along with other elasmobranchs, Hypanus sabinus and Hypanus say stingray are common, particularly in shallow-water areas along the shorelines. Life-history parameters of these species are poorly-known, including diet. In particular, the diet of an organism provides crucial information such as prey selection, prey abundance, and population shifts of both the stingray and prey species, and more. Traditional diet research used visual identification of partially digested prey in the stomach, but soft-bodied prey ingested by many batoids tend to be quickly digested. For this study, three separate techniques have been applied to better quantify prey items and assimilation for these two stingray species: stomach content analyses, DNA metabarcoding, and stable isotope biogeochemistry. A 129-sample set was examined from H. sabinus (n= 67) and H. say (n=62) using stomach content analysis, a subsample of 5 individuals were selected for investigative metabarcoding analysis using three techniques. Polychaetes, shrimps, crabs, brittle stars, and small fishes were the most abundant findings to date. Stable isotope analysis will also be applied as a different approach to measure the flux of organic elements across the ecosystem through diet analysis. Detecting dietary trends of H. sabinus and H. say such as seasonal or ontogenetic diet preferences is vital for understanding general knowledge of the two species and broader IRL ecosystem health.
A Stingray’s Preferred Menu: A Wide Selection of Small Invertebrates
HCAS Guy Harvey Oceanographic Center, Nova Southeastern University
The Indian River Lagoon (IRL) is a brackish estuarine ecosystem along the Atlantic coast of Florida. Along with other elasmobranchs, Hypanus sabinus and Hypanus say stingray are common, particularly in shallow-water areas along the shorelines. Life-history parameters of these species are poorly-known, including diet. In particular, the diet of an organism provides crucial information such as prey selection, prey abundance, and population shifts of both the stingray and prey species, and more. Traditional diet research used visual identification of partially digested prey in the stomach, but soft-bodied prey ingested by many batoids tend to be quickly digested. For this study, three separate techniques have been applied to better quantify prey items and assimilation for these two stingray species: stomach content analyses, DNA metabarcoding, and stable isotope biogeochemistry. A 129-sample set was examined from H. sabinus (n= 67) and H. say (n=62) using stomach content analysis, a subsample of 5 individuals were selected for investigative metabarcoding analysis using three techniques. Polychaetes, shrimps, crabs, brittle stars, and small fishes were the most abundant findings to date. Stable isotope analysis will also be applied as a different approach to measure the flux of organic elements across the ecosystem through diet analysis. Detecting dietary trends of H. sabinus and H. say such as seasonal or ontogenetic diet preferences is vital for understanding general knowledge of the two species and broader IRL ecosystem health.