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Island Grey
Fox About 16,000 to 18,000
years ago the world experienced its last major ice
age. Much of the ocean's water had turned to ice
and the level of the remaining seas were lower than
they are today. The Santa Barbara channel off the
coast of southern California in North America was
narrow enough for animals to cross over. One of
these animals was a relative of the
grey
fox. When the ice age
ended, and the ice began to melt, the sea levels
rose. Over time the foxes found themselves cut off
from the mainland on a string of islands. Today the
island grey fox can still be found on six of the
largest of the Channel Islands 19 to 60 miles off
the coast of southern
California. These are the islands of Santa
Catalina, San Clemente, San Nicholas, San Miguel,
Santa Cruz, and Santa Rosa. The Channel Islands have a
Mediterranean climate which is hot and dry in the
summer, and cool and wet in the winter. In America
it is know as chaparral. There are many different
types of habitats on the Channel Islands. There are
valleys and foothill grasslands, coastal
sage/scrub, sand dunes, coastal oak and pine
forests, and marshes. The island grey fox lives in
all of them. Many people don't even
know the island grey fox exists. Its not hard to
overlook these distant cousins of the mainland grey
fox, they are tiny. They became smaller by a type
of evolution called natural selection. Because
there is a limited supply of food, water and
territory on an island, large foxes had a hard time
surviving. But when a small runt of a fox was born,
it didn't need as much food or territory. This
would enable it to survive to a breeding age and
pass its small genes along to the next generation.
Over time the foxes became smaller and
smaller. It is actually the
smallest fox species in the United States and is
almost as small as Africa's fennec fox. It only
stand 5 to 6 inches tall at the shoulders and
weighs 3 to 4 pounds. Females weigh a little less
than males. Its head and body lengths range from 19
to 20 inches, and the tail is about 4 to 12 inches
long. The tail actually has two less vertebrae than
the mainland grey fox. The island grey fox looks
very much like its larger cousin, the mainland grey
fox. Its coat can range from cinnamon, light grey
or red, but is mostly a combination of all these
colors. The chin, lips, nose, and the areas around
the eyes are outlined in black. Its ears, neck and
the sides of its legs are usually cinnamon. The
tail has a thin black stripe on the top side while
the bottom side is cinnamon. Young foxes usually
have a paler and thicker fur coat and their ears
are a darker color compared to the adults. From
August to November the island grey fox molts, or
gets a new coat of fur. Their old fur coats fade in
color and the tips of the hairs curl at the ends.
Although it is only as
large as a house cat, the Island grey fox belongs
to the Canidae family, the same family wolves,
coyotes and domestic dogs belong to. The island
grey fox is also the only carnivore found nowhere
else except in California. Island
grey foxes mate for life, but they only
stay together to mate and raise their
pups. Then they are off by themselves
until the next breeding season. They only
breed once a year between January and
April. The female, or vixen, will give
birth to a litter of kits 50 to 63 days
after mating. Litters usually have 2 to 3
kits, but can have as few as 1 or as many
as 5 kits. The kits are born in dens in
ground holes, hollow trees, rock piles,
shrubs, and caves. The parents find these
and don't actually make the dens
themselves. They are born blind and
helpless with short dark brown hair and
only weigh about 5 ounces. The mother
nurses them The island grey fox is
solitary and diurnal, being active mostly in the
early morning and in the evening. They hunt mostly
during the day, but are known to move around at
night. Island grey foxes are called omnivorous
because they eat both plants and animals. Depending
on where they live their diets can consist of
mostly insects and fruit like manzanita, toyon,
saltbush, prickly pear, and the fruit of sea-figs.
They will also eat deer mice, birds, lizards, land
snails and any garbage people leave out. They communicate with each
other through sight, sound and smell. They use
their body postures and facial expressions to show
dominance, and bark and growl at each other. They
mark their territories by leaving a few drops of
urine around the borders and leaving their scat in
obvious places like trails. This tiny fox is
described as being docile, playful and
affectionate. When first approached by humans it
will growl, but soon it tolerates the human and
becomes curious. Not that you should try to pick
one up, if you ever see one. That wouldn't be safe
for you or the fox. The island grey fox has
been dying at an alarming rate during the last
decade. The main causes were discovered to be
diseases from domestic pets humans have brought to
the islands, and the golden eagle. Because they
have been isolated on the islands for thousands of
years they haven't built up an immunity to the
diseases and parasites brought over by animals from
the mainland. Thousand of years of breeding within
a small gene pool has also created a small genetic
variation, which makes them susceptible to
diseases. By 2000 there was a 95% decrease in the
population on the northern three Channel Islands
over a span of only four years. The
National
Park Service, which owns
some of the islands, won't allow you to bring your
dogs or cats into the Channel Island National
Park. Golden eagles are also a
major threat to the island grey fox. These
beautiful birds haven't always lived on the Channel
Islands. They were attracted to the islands by the
wild pig population and settled permanently around
1995 when the larger, fish-eating bald eagles died
out in the area from DDT, hunting and egg
collecting. Their arrival on San Miguel island that
year coincided with the first decline in the island
grey fox population. At that time there used to be
about 450 grey foxes living there, but only 40
survive today. In 1999 the golden eagles began to
nest on Santa Cruz and the population there went
down from 2,000 in 1994 to only 60
today. The island grey fox is
protected by California state law, and is listed as
threatened. In 1996 the IUCN listed Urocyon
littoralis as Lower Risk/Conservation Dependent.
This means that the island grey fox can't survive
unless humans intervene on its behalf. Island grey
foxes are dependent on captive breeding programs on
San Miguel, Santa Rosa and Santa Cruz for their
survival. They are bred in captivity and then taken
to other areas to try to raise their
population. In 1999 the National Park
Service together with The
Nature Conservancy
established an Island
Fox Recovery Team to look
into the problem of the population decline. They
recommended that the following things be done:
The Park Service and The Nature Conservancy are
also workin on restoring the natural ecosystem and
elimination the feral pigs off Santa Cruz
Island. So far the Park Service
has set up sanctuaries and captive breeding
programs on San Miguel and Santa Rosa Island.
Thirteen of the golden eagles have been captured
from the Santa Cruz Island and relocated by the
Santa
Cruz Predatory Bird Research
Group. Only a few golden
eagles remain to be moved. By the year 2004 a dozen
American bald eagles were released on Santa Cruz
Island, and ten more bald eagles from Alaska will
be joining them. On March 5, 2004, the U.S. Fish
and Wildlife Service listed the subspecies Santa
Cruz Island Fox as endangered. In the spring of 2004 the
first two wild kits were born on Santa Rosa. Since
the year 2000 no wild foxes had existed on the
island. They join 9 other kits and 7 adults who
were all raised in captivity. The National Park Service
needs our help to save the island grey fox. Their
populations have declined so rapidly on all six
Channel Islands that it needs help in raising funds
for their recovery program. The National
Park Foundation has set up an
Island Fox Fund and hope to raise money and spread
awareness about this critically endangered
species What happened to the
island grey fox is a good lesson on how ecosystems
and their inhabitant rely on each other. Change one
element in the system and a species could become
extinct. Until about 1995 the island grey fox had a
strong population able to take care of itself. Then
something happened to the bald eagle with which
they had no contact. This created an opening for
the golden eagle, which had avoided the larger bald
eagle up till then. This changed everything for the
island grey fox as they became easy prey for the
golden eagle. Within 7 short years the island grey
fox is teetering on extinction because one species
was removed from their ecosystem.
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