Environmental Biology of Fishes

, Volume 97, Issue 9, pp 981–997 | Cite as

Quantitative food habits of the bullnose ray, Myliobatis freminvillii, in Delaware Bay

  • John A. Szczepanski
  • David A. Bengtson


Feeding habits of many batoid elasmobranchs have been recorded, but diets, prey selection, and resource partitioning within specific populations are not fully understood. Few descriptions exist of the diet of a batoid species throughout its entire life history. Through gut content analysis, our research examined the feeding habits of the bullnose ray, Myliobatis freminvillii, to understand the diet and trophic role of this species in the Delaware Bay at various life stages. We were able to collect a higher abundance of neonate and juvenile rays than expected allowing for a more comprehensive diet characterization than in past studies. Over the course of 2 years, 160 specimens were collected through fisheries-independent trawl surveys, of which 132 had stomach contents. Overall, this species feeds mainly on hermit crabs and gastropods, with some bivalves as well. Diet was shown to vary across months and across life history stages. Diet data for the various months and life stages of this species in Delaware Bay can provide new information for future efforts in conservation, ecosystem-based fisheries management, and modeling.


Myliobatis freminvillii Feeding ecology Diet characterization Elasmobranch biology Resource partitioning 



Thanks go to Cliff Katz, Ted Durbin, Jeremy Collie, and Brad Seibel for their intellectual advice and statistical help. Sample collection was only possible with the help of the RI Department of Environmental Management and the DE Department of Natural Resource and Environmental Control; specifically, the crews of the R/V Chaffee (Scott Olszewski and crew) and the R/V First State (Stewart Michels and crew). Sample processing and cataloguing were greatly facilitated by Peter Schooling, Christina Lemnotis and Juliana DeLuca. I need to thank Joe Bizzarro for further advice on statistics and techniques and Matt Ajemian and Julie Neer for organizing the Stingray Biology Symposium of JMIH 2013. The Save Our Seas Foundation and the American Elasmobranch Society funded the presentation of research and publication of this manuscript whereas the URI Research Office, the URI Biology Department and the College of Environment and Life Sciences, the Graduate Student Associate and the Graduate Assistants United of URI all contributed to financial assistance for travel and presentation of this work. This research was conducted with the approval of URI’s Institutional Animal Care and Use Committee.


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of Biological SciencesSalve Regina UniversityNewportUSA
  2. 2.Department of Biological Sciences, College of the Environmental and Life SciencesUniversity of Rhode IslandKingstonUSA

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