Poster presentation 12th International Mammalogical Congress

Temporal reduction in the abundance of Lynx rufus: Evidence from camera-trapping and DNA-analysis (#639)

Pedro Galetti 1 , Charli N Davis 2 , Fernando Gonçalves , Bruno Saranholi 1 , Trevor Herbert 3 , Rodolfo Dirzo 2
  1. Genetics and Evolution, Universidade Federal de São Carlos, São Carlos, São Paulo , Brazil
  2. Stanford University, East Palo Alto, California, United States of America
  3. Jasper Ridge Biological Preserve, Woodside, California, United States of America

Due to the elusive nature and low densities of wild felids, traditional mark-recapture methods for estimating population size are often insufficient to guide appropriate conservation actions. Furthermore, wildlife ranges are often reduced by ever-expanding urban landscapes, making it difficult to study elusive felids and maintain stable populations. Therefore, developing effective methods to assess felid populations in human-dominated landscapes is vital to understanding the future of these populations. We examined the spatial distribution and abundance of the bobcat (Lynx rufus) at Stanford’s Jasper Ridge Biological Preserve (JRBP), combining camera-trapping and DNA-analysis data. JRBP is a 485 hectare preserve surrounded by urban environment in Woodside, California. This study is the first to assess bobcat population in this area using both camera-trapping and DNA-analysis techniques. Initial surveys were done from 2006-2008 and 2014-2015 using mark-recapture camera-trapping methods. We conducted additional surveys in the summer and fall of 2016 employing a non-invasive, scat DNA-based capture-recapture framework, compared to concurrent camera-trapping surveys. A comparison of the three time-points shows that there has been a substantial decrease in the bobcat population, with population estimates of 25 bobcats in 2006, around half that number in 2014, and 7 in 2016. When comparing the two sampling methods (camera-trapping, scat DNA-analysis), we found higher capture rates using DNA-analysis techniques. Our genetic approach combined with traditional camera-trapping improves upon traditional mark-recapture techniques, likely providing a more reliable method for monitoring low-density wildlife populations.