ALBANY: Dr. Roland Kays, Mammalogist with the New York State
Museum, explained to a large, appreciative Save the Pine Bush
audience, why carnivores are important to ecosystems. Carnivores
have a “top down” effect on ecosystems. For example, wolves
eat moose, who eat plants. A change in the number of wolves
will affect a change in the number of moose, which changes the
vegetation in the ecosystem.
Or, coyotes are known to eat cats. The population of coyotes
has an effect on song birds; the more coyotes, the fewer cats,
the more song birds. Or, the fewer the coyotes, the more cats,
the fewer the song birds.
Two top carnivores in New York State have disappeared, the
wolf and the cougar. Losing these top predators changes the
ecosystem. The coyote moved in when the wolf became extinct
here. Coyotes arrived from Canada in the 1950s, finding good
habitat such as abandoned farm lands. Coyotes are abundant and
have been increasing in number in the past 10 years.
Eastern coyotes are bigger than western coyotes, but are still
only about 1/2 the size of a wolf. Little is known about eastern
coyote ecology. DNA analysis is expected to be completed soon.
The big questions about carnivores are which, where, and why
— classic museum work. With new, modern methods, study of carnivores
is affordable and more sophisticated than in the past.
New methods include camera traps and fecal DNA analysis. These
methods, combined with traditional methods of live-trapping,
radio tracking and scat collection can give scientists a great
deal of information about carnivores.
Camera-trapping involves placing a camera with a motion detector
in sight of bait. The pictures are time and date-stamped. Caught
in Kay’s camera’s eye were the fisher, gray fox, raccoon and
a few miscellaneous homo sapiens. The fisher is a brown/black
weasel-like animal that is making a remarkable comeback. Trappers
catch fishers for their fur.
Kays has two years of scat (feces) collected. Using fecal DNA
analysis, Kays can identify the species, the sex ratio of the
animals, and specific individuals. With camera-trapping, it
is hard to determine if it is many individuals being photographed,
or one individual being photographed many times. With fecal
DNA analysis, scientists can easily identify individual animals.
Live-trapping, a traditional method of studying animals, has
advantages. However, the disadvantage is that it is time intensive
and carnivores are hard to catch. Kays has used mark/release
to study carnivores.
Radio-tracking is another traditional method of study which
gives very detailed information about where creatures live and
roam. However, it is also very time-intensive.
Kays’s studies show that the two major carnivores found in
the Pine Bush are coyotes and raccoons. In the Pine Bush, skunk,
weasel and red fox are not common.
Kays studies carnivores in the Pine Bush because the Pine Bush
is a place of high conservation interest and intense development
pressure. He studies carnivores in relation to fragment size
of the ecosystem, isolation of these fragments, and the ecosystem
of the land surrounding the fragments.
For his studies, Kays has identified 22 ecosystem fragments
in the Pine Bush from 1 to 400 hectacres in size.
For coyotes, Kays’s research has produced some important information.
His studies show that the coyote population may be increasing
in size, but more study is needed. Coyotes do have an impact
on the deer population by probably eating fawns. Coyotes do
eat cats, but not many. Coyotes don’t eat livestock, are not
much of a threat to people, and are different from Western coyotes.
Scat analysis show coyotes eat primarily cottontail rabbits,
deer, plants and fruits in the fall, insects, very very little
garbage (this is good!), a kitten and a grey squirrel. This
is a very good sign that coyotes eat primarily natural foods,
and not garbage.
Radio-collar research has shown that coyotes stay primarily
in the largest fragments of Pine Bush ecosystem, and not near
the suburban areas. They don’t cross highways or roads at all.
The home range of coyotes in the Pine Bush is only 5 square
km, as opposed to coyotes in Cape Cod (30 square km) or the
Adirondacks (112 square km).
The known coyote deaths include one from trapping or shooting,
one killed on a highway off-ramp, and one mystery death of a
healthy coyote found curled up in the woods. “Its not easy being
a coyote” said Kays.
Kays studies of cats have produced some interesting findings.
The main question is, “Are cats a threat to nature preserves?”
There are a few hundred cats bordering the Pine Bush preserve.
Of these, 1/3 go outside. They hunt mostly common mammals, such
as mice. They almost never go into the Preserve, and prefer
the small fragments of ecosystem. Kays speculates the cats stay
away from the large fragments to avoid the coyotes.
Dr. Kays will be part of a Pine Bush Lecture Series, hosted
by the NYS Museum called “The Albany Pine Bush: Biology and
Conservation of a Suburban Oasis” The series will be held Wednesday
evenings, 7:00 PM, during the month of May at the Museum.
Printed in the February/March 2002 Newsletter