Bobcat Isotope Analysis

In the fall of 2017, Furbearer Conservation's licensed trapper, Jeff Traynor, was approached by local independent biologists in search of data. Isotopes are chemical signatures incorporated into all growing tissues proportionately to the signature of whatever an animal eats. In the case of bobcats, all prey items will have slightly different isotope ratios based on their diet. For example, hares eating mostly grasses and herbaceous plants will have different ratios than beavers eating mostly bark and cambium and both will be different from grouse eating acorns and berries. By collecting isotopes of bobcat prey, scientists can piece together how important each prey species is in a bobcat's diet.

Jeff extracts hair samples from every trapped furbearer to assist with this continued research. Another prime example of NH's trappers giving back to conservation of wildlife.


 Hair samples from Jeff's harvested furbearers are collected and sent to UNH biologists. Image furnished by Jeff Traynor (Furbearer Conservation™)

Hair samples from Jeff's harvested furbearers are collected and sent to UNH biologists. Image furnished by Jeff Traynor (Furbearer Conservation™)

From University of NH:

"Scientists theorize bobcats have rebounded, in part, because they have shifted their diet to different prey, such as turkeys and squirrels that hang out beneath bird feeders during the winter. To test their hypothesis, they will compare the stable isotope signatures – different forms of chemical elements such as nitrogen and carbon -- in possible prey animals with those in bobcat hair. The idea behind the analysis is that isotope signatures in a top predator are a reflection of foods consumed at different ecological levels.

They also want to understand if bobcats that live in more developed areas are subjected to higher levels of stress. To do this, scientists will compare levels of a stress hormone called cortisol in hairs from individuals living in developed areas with those from individuals in more rural areas."