Shark food is where it's at

For sharks, it’s more where they eat than what they eat—at least when it comes to feeding patterns. Scientists have known little until now about the foraging habits of the world’s 500 or more shark species. Thanks to a new study—led by UK researchers Christopher Bird and Clive Trueman, and co-authored by biologists Francis Juanes and Amy Teffer now at the University of Victoria—it’s clear that coastal sharks have very different ways of feeding than sharks in the deeper ocean. The conservation implications for globally declining shark populations are significant.

The international team representing 73 scientists from 21 countries used carbon signatures to show on a global scale where sharks get most of their nutrients. The new research indicates that shelf-dwelling sharks living near coastlines feed locally across a range of areas, but deeper ocean sharks get most of their food from specific areas of colder, productive water in both the northern and southern hemispheres. This knowledge will help shark conservation by emphasizing how much sharks rely on coastal habitats and mid-latitude open ocean areas, which in turn will be used to plan marine-protected areas and reduce fishing pressures on shark populations of the world.

Participating in this internationally collaborative study to describe where sharks eat and move means a lot, especially as a graduate student. I’m excited to see how our findings will contribute to global shark conservation.

—Amy Teffer

An international PhD candidate in biology at UVic, Teffer was born in the US and earned an MSc in 2012 from the University of Massachusetts, Amherst where Juanes was her advisor. Teffer and Juanes, along with former UMass Amherst PhD student Michelle Staudinger who is also a co-author on the new study, published a paper in 2014, which caught Bird’s attention and led to the two UVic researchers joining the synthesis study on global shark ecology. At the time, Teffer was working with recreational fishers to collect tissue and stomach samples from catches on Cape Cod and the Islands of Massachusetts.

“The strength of the results is the compilation of studies, bringing together researchers and global perspectives on a vital conservation concern,” says Juanes, a faculty member in the biology department who came to UVic in 2011.

The paper, “A global perspective on the trophic geography of sharks,” will be published in the February issue of the peer-reviewed journal Nature Ecology and Evolution.

More info on the international study: University of Southampton news release | uMass Amherst news release

Online campus story on this study: UVic News 

A press kit containing high-resolution photos and an infographic is available on Dropbox.

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