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Background Naushon's
mission to run a environmentally sustainable and
economically viable farm is confounded by presence
of the new keystone predator, and wolf
replacement, the coyote. Our
coyote is more formidable than its western
counterpart. As populations edged eastward
through Canada our coyote ancestors hybridized
with wolves. These backcrossed with
coyotes incorporating some of their genes.
Scientists think that, as a result, our coyotes
are larger, live in packs, and can hunt
cooperative for larger prey. Coyote
Benefits Coyotes
can perform a beneficial ecological service by
controlling prey populations. When coyotes
arrived on Naushon there was a documented plunge
in the deer population. This is typical
after the arrival of coyotes. It happens
to rabbits and foxes as well. The affected
animals have existed for generation without
wolves, their ancestral predator, and they have
lost their edge. Lack of predation
pressure from wolves has made them
evolutionarily sloppy. From the human
perspective the effect is devastating:
populations of prey animals plunge, sometimes
for years. The animals are not gone,
however. During those years there is rapid
natural selection for prey animals that
are more alert, more muscular, more
intelligent. This is the case on Naushon
today where deer are returning to sustainable
levels. Coyote
Problems On
the other hand, coexisting with coyotes requires
careful thought. Our research on the
Narragansett Bay Coyote Study (NBCS) has shown
that coyotes can learn to specialize on
particular foods. A coyote that eats dead
sheep will quickly learn to eat live ones.
However, those that are not allowed to develop a
taste for sheep ignore them. If farms get
off on the wrong foot with coyotes it can be a
difficult cycle to break with clear economic
impacts. GPS
collaring by NBCS in response to coyote
complaints in Rhode Island has also shown that
coyote problems stem from a common issue.
In our area are subsidized in numbers of ways by
anthropogenic food resources. These
include road-killed deer, unburied winter-killed
farm carcasses, careless disposal of garbage,
domestic animal food left outdoors, and the
wildlife feeders. Previous research has
shown that numbers of individuals in each pack
(a pack is a breeding unit or family group)
increase as a response to rich food
resources. Our work in Rhode Island is showing
that coyote pack territory size (area defended
by one breeding group) decreases when the
pack is richly subsidized by food. If
average pack size is smaller more breeding
groups can fit on the island. It appears,
therefore, that food subsidization of coyotes
may affect coyote populations in two ways
leading to larger packs in smaller territories. There
is a second problem with anthropogenic
subsidies. If the coyotes make the
association between the people and the food they
become habituated, losing their natural fear of
humans. Coyotes are often active during
the day. This can seem exciting,
unnerving, or dangerous, depending on your point
of view. Co-existing
with Coyotes on Naushon: Research Goals Since
coyotes are highly visible on Naushon and active
during the day we suspect that they may be
receiving significant food subsidies from
humans. Our first step is to examine
whether this is the case. We will be collaring
animals from two packs: an unsubsidized
pack on the west end and one on the east end
where we suspect subsidies may be affecting the
density of coyotes. Naturally
we suspect the "Gentleman's Exchange"
may be part of problem so we will trap our east
end coyote there. It will be interesting
to compare the numbers in each pack and the
territory size of each. GPS
collars will tell us the size and locations of
the pack territories. Numbers of coyotes
in each pack will be counted using motion- and
heat-activated video at scent posts we place in
core areas within each pack's territory.
If we find significant subsidization occurring,
our second step will be to suggest ways to
button things up. We will track the pack
density and territory size on the east end as we
look for a response to removal of
resources. We hypothesize that pack
numbers will drop and territory size will
increase. Since coyotes aggressively
defend their territories this could mean lower
coyote numbers on the east end. Our goal
is to force coyote numbers to drop to a level
sustainable by the natural resources
available on Naushon creating a safe and
sustainable relationship between coyotes and
human residents. We are very excited for
the opportunity to include Naushon in our
coastal coyote study and look forward to
reporting our progress to you as we go. Many
thanks to the family members and staff who have
encouraged us to pursue this project. N.
Mitchell
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