Forest Carnivore returns to Southeast Ohio
Posted by collegegreenou on November 13, 2009
By Audrey Rabalais
A small predator stalks its way through the night in Wayne National Forest, spotting a turkey feather on a tree and further enticed by the scent of beaver castor oil and catnip. It approaches the alluring trap, relieving an itch against blunt nails under the feather. With two quick camera flashes, the bobcat disappears, leaving only a few stray hairs and its picture on the film.
Wildlife biologists like Suzie Prange live for this hypothetical scenario.
“It used to be that I couldn’t wait to get my hands on an animal, but now just getting pictures is so great,” said Prange who is part of a bobcat research project aimed at documenting the distribution and abundance of bobcats (Lynx rufus) in southeastern Ohio.
Bobcats are an endangered species in Ohio, native to central and southeastern areas of the state. The mid-sized cat with black-tufted ears controls small rodent populations and is an essential component of the food chain and ecosystems to which it belongs.
During the 18th and early 19th centuries, bobcats were found throughout Ohio, but as more land was cleared for settlement and agriculture, bobcat numbers plummeted, and by 1850 the species was nearly extirpated. Since 1970, there have been 255 verified reports of bobcats in Ohio. A verified report requires physical evidence of the animal such as roadkill or a photograph. Prange said many of the reports are from people who call in to the local Department of Natural Resources office and many of these sightings remain unverified.
“We get a lot of just folks calling in saying, ‘I saw a bobcat,’ ” said Prange. Although unverified reports are not used to estimate bobcat populations, she said it appears that the unverified report trend supports the numbers of verified reports. Prange suggests that the increase in trail cameras bought by hunters and private landowners has lent itself to a larger number of reports in recent years.
The Ohio Division of Wildlife began conducting its bobcat camera trap and hair snare study in 2007 in three sites across southeastern Ohio. Each site was divided into a grid consisting of 12 one-square kilometer areas where hare snares and cameras were set up. The hair snares consisted of a square of carpet with blunt roofing nails inserted in it that could snag fur when the cats rubbed against it. The carpet was scented with beaver castor oil and catnip to attract the cats by scent. A turkey feather was placed above the carpet pad to attract them by sight as bobcats are flashers, predators attracted through movement.
Two infrared cameras were placed at 90-degree angles toward the scent pad and feather to capture footage of the bobcats that visit the site. Ideally, two picture angles would be captured of the visiting bobcats, Prange said.
After successful monitoring in the pilot study, 12 sites were set up and monitored during 2008 with photos obtained at four sites and hair sample at six sites. Wildlife biologists are now looking for patterns in the movement and territory of bobcats. Individual felines can be identified by DNA analyses of the hair samples, which are also used to estimate total density of the population. Individuals can also be identified by looking at pelage patterns, or the specific pattern of spots in the fur, which ideally are discernable from the photos taken.
Biologists involved with the bobcat project are also trying to determine if seasons affect bobcat detection rates. However, they are not speaking of your typical spring, summer, fall and winter; these seasons are based on the cats’ biology. The first season begins in May with birth and early kitten rearing, followed by late kitten rearing in August, dispersal in November and breeding in February.
To determine if seasonality affects bobcat detection rates, biologists will resurvey each site from 2008 at which bobcats were detected during the 2009-2010 survey. This will allow identification of the best time of year to survey the bobcats, generating more efficient surveying techniques and better bobcat management in Ohio.
Only four sightings may not seem much for a field site, but Prange said those pictures make the job worthwhile.
“After a long day in the field, I get into my car and turn the headlights on, driving away wondering if those bobcats are going up to the traps I just put up.”
Prange intends to continue the project as long as it lasts, already persevering through a pregnancy last year. She spoke of seeing video and pictures of herself out in the field, eight months pregnant.
“I look forward to when my daughter is old enough to see it and I can say, ‘There’s mommy! There you are looking for bobcats.’”
It appears that bobcats are back in Ohio to stay, and research on these cats is just beginning for dedicated biologists like Prange. Her research now may help ensure that her daughter grows up in an Ohio with a healthy bobcat population.