The Island Fox
(Urocyon littoralis)
By: Benjamin Campos
Background
At 12 to 13 inches in height and 4 to 5 pounds, the island
fox is about the size of a house cat, about 1/3 smaller than its
ancestor, the Grey wolf. Their small size can be attributed to the natural
selection of a smaller size in response to overcrowding, food limitations and
genetic variations. The Island Fox’s coat has a gray color on the back, rust
color on the sides, and white color underneath. Interestingly enough, the Island Fox is the only carnivore that is unique to the state of California.
Habitat
(Map courtesy of UC Santa Barbara) |
The Island Fox is native to the Channel Islands of
California, a group of 8 islands that are found off of the Coast of Los Angeles
county and Santa Barbara, in Southern California. There are 6 subspecies of the
Island Fox, all named after the native island on which they live on: Santa
Cruz, Santa Rosa, San Miguel, San Nicolas, San Clemente and Santa Catalina.
Even though there are six different subspecies that look similar, all of the
subspecies have their own distinctions. Although the six subspecies are
threatened, only four are currently listed as endangered due to their dramatic
population changes: The Santa Rosa, Santa Cruz, San Miguel and Santa Catalina
island foxes. Island foxes are believed to have been introduced by the Native Americans that populated the islands since there is no evidence of any other way the foxes would have been able to arrive from the mainland. On the islands, the foxes inhabit all types of habitats such as coastal lands, chaparral and forests.
Reproduction
Island Foxes are k-species and monogamous, which means they only have 1 mate during their entire lifetime, and only reproduce once a year. Island foxes produce litters of 2 to 3 pups, on average, who spend their first month in a den, since they are born blind and therefore vulnerable. As seen below, pups are born much darker and furrier than their parents and remain that way for a couple of months.
Why are they threatened?
Golden Eagle |
You would not expect the Island
Fox (Urocyon littoralis)
to be their island’s top predator, based on its very diminutive size. However,
that was the case for thousands of years. The Island Fox enjoyed being the
island’s top predator until the 1990’s when Golden Eagles began nesting on the
islands from the mainland. Golden Eagles began to nest on the islands after Bald Eagle populations began to decreases in their populations due to their struggle with DDT contamination. The foxes, never before having been subject to
predation, became easy victims to these new-found predators.
Recovery Plan
All 4 subspecies of the Island Fox were listed as endangered in March 2004. Recent efforts to recover the Island Foxes from their endangered listing include removing Golden Eagles from the Channel Islands, as well as removing Foxes and placing them in captivity. Since Bald Eagles' diet consist of marine life and seabirds, they pose little threat to Foxes, but compete with the Golden Eagles. "From 2002-2006, the Institute for Wildlife Studies (IWS) released 61 bald eagles on Santa Cruz Island" (National Park Service). The foxes that are placed in captivity were bred with one another, and then released back to the wild. The reintroduced Island Foxes proved to be very successful reproducing and had a very high survival rate. The costs that were incurred for trying to recover the six species of Island Fox almost reached a value of $8,500,000. If the recovery plan goes as planned, it is estimated that the species could be recovered by the year 2020.
What Can You Do?
Since the Island Fox resides on an isolated island, there isn't much that one can do to directly help them. However, you can donate to organizations such as the "Friends of the Island Fox" program that exist in order to aid these creatures. "The Friends of the Island Fox" use donated funds in order to purchase necessary materials such as microchips or radio collars that are used in order to capture more foxes and place them in captivity (National Park Service). The size of the diminutive Island Fox, does not correlate to its large importance. The Island fox is a very crucial species to maintaining the beautiful ecological puzzle that is California.
Works Cited:
"Friends of the Island Fox: To Help." Friends of the Island Fox: To Help. N.p., n.d. Web. 02 Dec. 2015.
National Park Service. "Island Fox." National Park Service. N.p., n.d. Web. 2 Dec. 2015.
U.S. Fish and Wildlife Service. 2015. Recovery Plan for Four Subspecies of Island
Fox (Urocyon littoralis). U.S. Fish and Wildlife Service, Sacramento,
California. xiv + 180 pp
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ReplyDeleteThe Island Fox is such an interesting species to me! I love the fact that they are only native to California. I find it extremely interesting that the fox only has 1 mate for its entire lifetime.
ReplyDelete-Logan Chirigotis #BIO227Fall2015
The pictures are so cute! I wonder why there are plans to re-establish bald eagles on the islands, since golden Eagles were the cause of endangerment.
ReplyDelete#BIO227fall2015