UNDERSTANDING BOBCATS IN THE GRANITE STATE: A cooperative project led by the University of New Hampshire and the New Hampshire Fish & Game Department

 

Linking Molecules to Management

Bobcats are highly mobile and can disperse long distances. In the absence of physical barriers, such dispersal can potentially result in thorough mixing of their genetic material within a population. Over the last few decades, New Hampshire has experienced a rapid increase in human population, and to support this growth, a concurrent increase in infrastructure development. Roads and dense developments can pose real barriers to roaming bobcats. Optimal bobcat habitat is now patchily distributed and populations may be separated by urban and suburban development and by major highways. By modeling collision probabilities, we found that actual traffic volume is a better predictor of bobcat mortality in the state rather than road densities. The model has recently been confirmed by actual data on bobcat fatalities caused by collisions.

MapofCollisionProbablity
 
Roadkills
Mean probability of vehicular fatality for a first attempt of a bobcat crossing a road in New Hampshire (from Litvaitis and Tash 2008).

 

Number of bobcat vehicle mortalities (n = 57) by township (2007 – 2011) and road density in New Hampshire (from Broman 2012).

From the above figures, it is clearly evident that major interstate highways (I-95, I-93, I-89), the Spaulding Turnpike, SR 101 (Seacoast to Manchester), and SR 3 (Manchester to Nashua) present formidable barriers to bobcats, and it is highly likely that as a result, populations are isolated from each other to varying degrees.

Such isolation can be measured using a population genetic approach. As geographic distance and isolation increase among populations, genetic similarity will decrease. Using microsatellites (a standard population genetic marker), we are currently testing the effects of major highways on the genetic diversity and population subdivision of NH bobcats. Ultimately, the results will be combined with data on habitat suitability to identify movement patterns of bobcats. Information on genetic connectivity of a wide-ranging animal can be used to identify important habitat linkages and wildlife corridors that will inform road planning and enhance strategic land acquisitions.

Using Historical DNA to Understand Current Bobcat Populations

Bobcatskull

New techniques allow us to extract DNA from a collection of bobcat skulls dating to the 1950s and early 60s. The skulls were prepared by the late Dr. Stevens and are associated with information regarding location, sex, body weight and physical condition. Using population genetic analyses we will estimate historical population sizes of NH bobcats and determine if significant changes have occurred since.

We can also combine locations of historical records with GIS to construct models of historical geographic distribution, and to determine how the availability and extent of suitable habitat has changed. This information will give us a glimpse into the historical status of bobcats, and will provide data on what the effects of human activities and habitat loss were on their genetic diversity. Our overall goal is to determine if patterns of genetic population divergence in today's bobcats reflect the recent or a historic landscape.

 

To report problems or broken links, please contact m.litvaitis@unh.edu