the bloodstream that trigger a “fight or flight” response. Chronic
stress can cause a decreased immune function that increases
susceptibility to disease and parasites. High stress levels
also inhibit growth and reduce reproduction. Because stress
hormones in the bloodstream are incorporated into growing
tissue, including hair, these researchers have a signature of
the stress levels a bobcat has experienced since its last molt.
Preliminary results show that bobcats living in more developed
landscapes do indeed show signs of greater stress, but it isn’t clear
yet whether the levels of stress detected are detrimental to the
health of the bobcats.
Living with humans presents obvious challenges to bobcats,
but there also may be consequences of revitalized bobcat
populations for humans. Nearly all wild animals have some
capacity to spread diseases or parasites to humans and their
pets. Bobcat fever, for instance, is caused by a protozoal
organism transmitted to domestic cats by tick bites, and the
natural reservoir host is the bobcat. This disease can be fatal to
house cats, and the number of infections may increase as bobcat
populations increase. The disease may be limited by the range
of the lone star tick; it has reached as far east as Pennsylvania.
Bobcats can transmit rabies, but given their scarcity, humans are
far more likely to encounter a raccoon, skunk, or fox with the
disease than they are to encounter a rabid bobcat.
On the other hand, research in the western United States
has revealed that humans and their pets can transmit diseases
to bobcats. Toxoplasmosis is caused by a parasite and can be
carried by healthy people with little or no effect, but it can cause
complications for infants and adults with compromised immune
systems. Toxoplasmosis can be spread by eating poorly cooked
food that contains cysts, exposure to infected cat feces, and
to a fetus during pregnancy if the mother becomes infected.
The parasite is only known to reproduce sexually in wild and
domestic cats. Bobcats living near urban areas in California have
been found to have higher rates of infection than rural bobcats
possibly as a consequence of encounters with domestic cats.
With the increase in sightings of bobcats, I often receive
questions regarding potential bobcat attacks. Yes, bobcats are
very capable predators. So chickens, domestic ducks, and turkeys
warrant husbandry techniques that protect them from all
predators – not just bobcats. Cats and small dogs left unattended
may also be vulnerable to a hungry bobcat. A recent news story
about an attack on a small dog in suburban Massachusetts by
a family of bobcats (a mother and two kittens) alarmed many
viewers, but such attacks are quite rare. It is important to
acknowledge that human populations have expanded into the
habitat of bobcats and other species. With time, bobcats have
adapted to a changing environment. Now, it is our responsibility
to ensure this magnificent animal will continue to thrive.
John Litvaitis has worked as a wildlife ecologist for county, state, and federal natural
resource agencies in New Jersey, Florida, and Oklahoma. After 31 years as a professor
at the University of New Hampshire, he is “re-wiring” his career as a full-time advocate
for wildlife. John lives in Madbury, New Hampshire. A male bobcat.