[A version of this article appeared in the Brown County Democrat on 3/13/18].
by Leslie Bishop, Ph.D.
From endangered to prize booty, the bobcats in Indiana continue to have a questionable future.
Populations of bobcats had plummeted in the state due to loss of habitat and over-harvest. In 1969, bobcats were protected as a State Endangered Species. In 2005, bobcats were removed from the State Endangered List and demoted to Species of Special Concern. This year their protection will come to a halt if DNR gets its way. The Indiana DNR is proposing the inclusion of bobcats for hunting and trapping.
This change in policy is not grounded in solid science. A population study has not been completed. In a survey of state wildlife management agencies (Roberts and Crimmins, 2010), the authors list Indiana as monitoring bobcats through public sightings and incidental harvest with an unknown population estimate. Since that study, DNR reports that additional information is being collected on vehicle collision mortality, Archer’s Index (a special program where bow hunters can report wildlife sightings), and sporadic trail camera use (Snapshot Indiana, Citizen Science Trail Cams).
All of these methods can be useful in describing the presence-absence and distribution of bobcats, yet none of them can predict population size (Caley, Hosack, and Barry, 2017). Use of trail cameras is becoming an increasingly useful tool in wildlife studies but can be used in population estimates only if there is consistent data collection over a given sampling period, a large sample size, and identification of individuals for mark-recapture data (Burton et al., 2015).
Vehicle collision mortality can be used in population estimate models if average speed, rate of traffic flow, and specific time periods are also known (e.g., Hobday and Minstrell, 2008). In addition, information about topographic features and highway construction variables is essential when making inferences about roadkill data (Finder, Roseberry, and Woolf, 1999). In the case of southern Indiana, we need to see data that tracks the incidence of roadkill with the construction of I-69. Has roadkill increased due to a new interstate with increased traffic and higher speeds? Specific locations of bobcat road mortality through time must be analyzed for consistency. But to date, these data are missing.
A population estimate requires agency resources (staff time and financial support), and thus far these resources have not gone into bobcat research. In the 2015 Indiana State Wildlife Plan (SWAP) report, the bobcat database was flagged as in need of statistical population reconstruction. The technical experts participating in the Modeling Focus Group suggested a group of terrestrial species as candidates for landscape-level modeling, but bobcats were not chosen (SWAP 2015).
At this time, we do not have a population estimate of Indiana bobcats, and therefore cannot know what a viable population is or whether the population size is above or below that level. Without these data, it will be impossible to fully understand the effect of hunting/trapping on Indiana bobcat populations as well as to accurately determine the needed limit on annual bobcat harvest.
DNR also claims that a regulated season will cut down on poaching and illegal marketing of bobcat pelts. Without a number (or estimate) of poachings or illegal sales, it is impossible to infer that the cost of allowing the harvest of hundreds of bobcats would outweigh the benefit of stopping a handful of poachers. By opening a trapping season with a bag limit of one animal, it may become even easier to abuse the system and take more individuals. It may become harder to identify illegal marketing as well. The actual regulation and enforcement of limited trapping seasons with bag limits is difficult due to minimal staffing of conservation officers in the rugged terrain of southern Indiana. Ecological decision making should not be driven by lack of enforcement.
There is no good reason to manage bobcat populations through trapping in Indiana. DNR admits that there have been no reports of negative effects on humans or family pets. In fact, an increased bobcat population is beneficial since their main diet includes rodents and rabbits.
A few trappers will benefit from the sale of bobcat pelts. Bobcat pelts from the eastern US and Canada yielded between $81.00 and $85.00. But with the limit of one bobcat per trapper, the benefit is limited.
Most of us have never seen a bobcat in the wild. These solitary and secretive animals play an important ecological role as predator in our forests. Instead of managing them through hunting and trapping, let us celebrate their comeback.
Please tell DNR not to include bobcats in hunting/trapping season. Submit your comments to DNR by 5 p.m., Friday, March 23.
You can also attend a public hearing on in Anderson on March 22, 2018, 5:30 p.m. ET at the Mounds State Park Pavilion.
Literature Cited
Burton, A.C., Neilson, E., Moreira, D., Ladle, A., Steenweg, R., Fisher, J.T., Bayne, E. and Boutin, S., 2015. Wildlife camera trapping: a review and recommendations for linking surveys to ecological processes. Journal of Applied Ecology, 52(3):675-685.
Caley, P., Hosack, G.R., Barry, S.C., 2017. Making inference from wildlife collision data: inferring predator absence from prey strikes. PeerJ 5:e3014. https://doi.org/10.7717/peerj.3014
Finder, R.A., Roseberry, J.L. and Woolf, A., 1999. Site and landscape conditions at white-tailed deer/vehicle collision locations in Illinois. Landscape and Urban Planning, 44(2-3):77-85.
Hobday, A.J. , Minstrell, M.L., 2008. Distribution and abundance of roadkill on Tasmanian highways: human management options. Wildlife Research 35:712-726.
Roberts, N.M., Crimmins, S.M., 2010. Bobcat population status and management in North America: evidence of large-scale population increase. Journal of Fish and Wildlife Management 1(2):169-174.
The 2015 Indiana State Wildlife Plan is available online.
Leslie is a Professor Emerita of Biology at Earlham College.
