Coyotes
vs. ranchers: Millville research center works toward
a solution
By Jessica
Allen
May 4, 2009 | CACHE COUNTY, Utah -- On a ranch out
in Tremonton, a herd of 1,800 sheep graze and rest quietly
as a stealthy, wiry predator calmly stalks a nearby
lamb. Running swiftly and taking it down, the predator
bites the throat of the young lamb, making it the killing
blow.
Braden Jensen, a student studying agriculture at Utah
State University, said that his family has tried numerous
ways to protect their herd of sheep, but nothing has
been completely successful at keeping the coyotes away,
a problem that a lot of farmers and ranchers face.
Jensen's family has been raising sheep and dealing
with coyotes for four generations and see the predators
as an expected annoyance when it comes to the business,
he said. They own sheep in Tremonton and Penrose with
summer ranges in Avon and Liberty, Utah.
"You know it's going to be a problem, so it's more
of an annoyance," Jensen said about raising and losing
sheep to predatory animals.
Out in Millville at the USU Predator Research Facility,
Dr. John A. Shivik, supervisory research wildlife biologist,
said that at the facility they study coyote behaviors
and habits to try and help ranchers and farmers with
coyote problems. The goal of the facility, he said,
is to find a way to keep coyotes living where they are,
but to stop them from preying on the livestock.
At the facility over 100 coyotes, born and raised
there, are studied by researchers and students from
USU.
Coyotes that mostly prey on livestock usually go after
sheep and goats, Shivik said, but sometimes they may
prey on calves too.
Garrett Snow, a student at USU, said his grandfather
used to own a couple hundred head of cattle out in Roosevelt,
Utah for 20 years and that coyotes were something that
they had to deal with.
"Every now and then he would lose a calf," Snow said.
The coyotes would usually work as a pack to separate
it from the protective mother and kill it.
However, Snow said, the coyotes most often get the
calves when they were separated from their mothers and
the rest of the herd to be weaned and that they were
small enough still that a single coyote could kill one.
One year it was particularly bad when it was dry in
the mountains and there was less prey, causing the coyotes
to go after bigger game than they normally would go
for, resulting in more cattle loss than usual, Snow
said. He said his grandfather probably lost two or three
calves a year to coyotes, and that the way that they
usually dealt with them was to go out and hunt them.
Coyote packs usually consist of two adults and whatever
offspring they have that survive to maturity, Shivik
said, but packs can be as large as 12 adults in some
areas.
Coyotes are very smart and adaptable, Shivik said,
and can live in the country or in urban areas where
they can be a threat to humans.
Shivik said that coyote populations are larger now
than they were before humans moved into the areas where
they lived. People brought in trees that didn't use
to be here and put in ditches with water and canals,
and inadvertently created environments for coyotes to
thrive, especially when they brought in livestock.
In Utah, studies done in 1999 by the National Agricultural
Statistics Service, also known as NASS, showed that
in the United States coyotes were the leading predator
and were responsible for the loss of 165,800 sheep and
lambs in that year, resulting in the total national
loss of $9,637 for ranchers.
NASS reported that in 1999, coyotes were responsible
for the loss of 12,000 lambs and 3,800 sheep in Utah
alone.
Jensen said that they have about 4,000 to 5,000 lambs
born each year, as about 70 percent of the ewes had
twins, and said that they probably lost a couple hundred
lambs a year to coyotes.
Another problem, Shivik said, is that coyotes and
sheep have their offspring at the same time of year,
in April.
"One of the motivations for coyotes is if they have
pups they need more food and then they'll eat those
lambs," Shivik said about why there is an increase for
coyotes with pups to prey more on sheep and lambs than
those that do not.
Not all coyotes prey on lambs, and many scientists
and studies are finding is that the coyotes that prey
on sheep is a learned behavior, states the information
booklet Lines of Defense: Coping with Predators in
the Rocky Mountain Region, written by Eric M. Geese,
Sean P. Keenan, and Ann M. Kitchen.
Shivik said some coyotes are perfectly happy hunting
rabbits, rats, other small rodents, and taking bites
out of watermelon without ever killing livestock.
Lines of Defense also states that although
most coyotes have the potential to prey on the livestock,
many don't -- further supporting that it is a learned
behavior.
"What one of our scientists has done was he went in
with helicopters and surgically sterilized packs," Shevik
said. "So those coyotes maintained their territory but
they didn't have pups, and he grazed sheep through places
with sterilized coyotes and not sterilized coyotes and
there was about a six-fold decrease in the lamb kills."
Lines of Defense also states that ranchers
and farmers that are not experiencing any losses to
the coyotes around them to let them be, because if they
remove the coyotes that aren't doing any harm to their
livestock or farms new coyotes may move into the territory
that will cause damage.
Ideal, Shivik said, would be to have coyote packs
that breed but do not prey on sheep or cattle that maintain
their territory. A coyote's territory can vary anywhere
from a couple of square miles to 10, he said.
Shivik said studies that the facility has done have
shown that coyote pairs mate for life, and that when
a female losses her mate she will leave the territory
to look for a new one, while if a male coyote loses
his he will try and bring one on to the territory.
But right now a perfect solution to the coyote problem
hasn't been found and ranchers and farmers try different
ways to deter the animals.
"We have found that each coyote is very different,"
Shivik said, "and that some are afraid of some things
and others aren't."
Shivik said that a lot of ranchers and farmers will
use bright flashing lights to try and scare coyotes
away as well as music, lamb sheds for when they are
first born, guard dogs or llamas.
Coyotes can also be dealt with either shooting them
on sight like a lot of farmers and ranchers do, or with
sacrificial type collars. The sacrificial collars may
be worn by a sheep if a rancher is having trouble with
a particular coyote; when the coyote attacks the ‘sacrificial
sheep' that is wearing the collar and bites into the
neck it will poison the predator.
It would take three years, Shivik said, killing 70
percent of the coyotes to reduce their numbers to make
a difference due to their reproductive capacity.
Some of the tactics that Jensen and others have used
have been tying flags or pieces of clothing to posts
or stings of wire around where the livestock graze.
But that hasn't worked and sometimes, Jensen said, a
trapper is needed to go out and take care of the coyotes.
The best defense against coyotes Jensen said his family
has found has been the guard llamas that live among
the sheep, and Great Pyrenees dogs, which are large
white dogs that are raised as pups with the sheep to
protect them.
Another great defense, Jensen said, is the three full
time sheep herders that travel with the animals.
Currently there is no perfect solution that will benefit
ranchers, farmers, and the coyotes but to keep trying
to deal with them to the best of their abilities and
trying different tactics, Shivik said.
"It's no big surprise," Jensen said, "coyotes are
just something you just have to deal with."
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