Tuesday, November 29, 2005

Where Does The Island Fox Live?

The island fox ( Urocyon littoralis ) is found only on the Channel Islands located between 19 and 61 miles off the coast of Southern California. Many of the islands can be seen from the shore on a clear day. Of the eight islands, foxes are only found on six. Each island has its own genetically different island fox subspecies.

California’s Channel Islands are each unique and, like the Galapagos Islands, a treasure of biodiversity.

The northern islands:

San Miguel Island is a sandy, wind-swept plateau with rocky beaches. There are no large trees or shrubs. It is only 8 miles long by 4 miles wide, yet it is the most important sea bird nesting site in Southern California. It also is home to one of the largest pinniped breeding colonies in the world, over 126,000 animals, including: the northern elephant seal, harbor seal, Steller’s sea lion, sea otters and the endangered northern fur seal and Guadalupe fur seal. Approximately 90% of the California sea lion population breeds on San Miguel and San Nicolas Islands.

Foxes share the rugged terrain with creatures unique to the Channel Islands – the silk-spinning sand cricket, Channel Islands slender salamander, Island western fence lizard, several island subspecies of birds, the endangered snowy plover and the bald eagle (reintroduced 2001).

Santa Rosa Island
is, for the most part, dry rolling hills of grassland. The other half is wooded canyons, coastal cliffs, wetlands, and sandy beaches. The island is 10 miles long by 15 miles wide. It is home to one of the rarest pine trees in the world - the Santa Rosa Island Torrey pine. Important fossil discoveries have been made on this island, including 13,000-years-old human remains and numerous pygmy mammoth skeletons.

Foxes share the grasslands with pygmy grasshoppers, island cicadas, and the island gopher snake. They also share habitat with an island species of spotted skunk and over 195 species of birds, including: the endangered snowy plover and bald eagle (reintroduced 2002). Six other species of plants are also endangered on this island.

Santa Cruz Island
has mountains, valleys, streams, and rugged coastline. It is actually two separate islands on opposite sides of a geological fault. Twenty million years ago the two pieces of land slid into each other to create one island. One half is volcanic, while the other half is layers of sedimentary rock. Ancient species of plants and animals from the two original islands can be found on the different sides of the fault (ie. the Channel Islands slender salamander on one side, the black-bellied slender salamander on the other). Many plants on Santa Cruz only grow in specific soils on one side or other of the fault. At 24 miles long and 6 miles wide, it is California’s largest island (3 times the size of Manhattan) and has the greatest plant and animal diversity of all the islands. It is also home to the world’s longest sea cave (1,227 ft.).

The fox preys on the Santa Cruz island deer mouse and the endangered Santa Cruz Island harvest mouse. It shares its varied terrain with other unique species – the island scrub jay, flightless katydid, Santa Cruz Island woodland skipper butterfly, the Santa Cruz Island cicada, and 10 species of plants found no where else in the world, including the Santa Cruz Island pine and the endangered Santa Cruz Island silver lotus.

Islands without foxes:


Anacapa Islands
are a volcanic string of three small islands with dry grassy bluffs, steep cliffs and black sand beaches. The eroded volcanic shoreline has a natural bridge and other scenic formations. At 5 miles long but 1/4 mile wide, the only native land mammal is the Anacapa deer mouse. However, this island is home to numerous island plants and is an important sea bird nesting site. It has the largest breeding colony of brown pelicans in California.

Santa Barbara Island is the smallest of the Channel Islands at only 1 mile long by 1 mile wide. Its steep, rugged volcanic cliffs rise to a grassy plateau with no trees. There is only one native land mammal, the Santa Barbara Island deer mouse, but there are 30 species of sunflower. This tiny island is an important sea bird nesting site and home to the largest breeding colony of Xantus’ murrelets in the world.

The southern islands:

Santa Catalina Island is the most populated of the Channel Islands and has a thriving recreation and resort area. Twenty-one miles long by 8 miles wide, the terrain includes mountains, steep canyons, woodlands, grassy hills, and rocky beaches. Bald eagles were reintroduced here in 1995, but DDT remains in the environment at high enough levels that the eagles are still unable to reproduce without human intervention.

This is the only Channel Island where foxes live with rattlesnakes and the two-striped garter snake. Foxes also share habitat with the Santa Catalina subspecies of deer mouse, harvest mouse, ground squirrel, California quail, Bewick’s wren, and 10 butterflies, including the Avalon hairstreak. Here, foxes live among numerous rare plants including the Santa Catalina Island ironwood and the endangered Catalina Island mountain mahogany. Marine mammals frequent but typically do not breed on this island because beaches are used by people, but the island is home to an arboreal salamander and 4 species of bats.

San Clemente Island is a dry grassy plateau (21 miles long by 3 miles wide) rising from the sea to steep cliffs at the far end. The U.S. Navy uses the island for training operations. This island has the largest number of plants found only on one Channel Island, including 8 endangered species and 138 species of lichen. The native plant life has been recovering since the removal of invasive exotic animal species.

The foxes on this island have had to learn to live in harmony with an endangered bird, the San Clemente loggerhead shrike. At one point foxes were removed from the shrike’s nesting area to save young birds. All island foxes in zoos come from this island. Foxes also share the island with the island night lizard, numerous birds and 4 species of bats.

San Nicolas Island is a grassy plateau with sand dunes (9.7 miles long by 3 miles wide). Because it was overgrazed by sheep and other exotic animals, no native trees remain. Today, the island is occupied by the U.S. Navy, but still remains an important breeding site for marine mammals. Sea otters were reintroduced beginning in 1987 and 90% of the California sea lion population breeds on San Nicolas or San Miguel. It is also an important sea bird nesting site.

Foxes share this windswept terrain with the San Nicolas Island deer mouse, the island night lizard,and a variety of island subspecies of birds, including Bewick’s wren, house finch, orange-crowned warbler, and horned lark.

Monday, October 10, 2005

CURRENT CONSERVATION EFFORTS

Saving the island fox and conserving its island habitat requires many different conservation efforts. The following are just a few of the actions currently taking place:

  • Island foxes on San Miguel, Santa Rosa and Santa Cruz islands have been taken into captive breeding facilities to ensure their survival and to increase their numbers to a level that facilitates their safe release back into the wild. On San Miguel and Santa Rosa, increased population numbers and the absence of golden eagles has allowed initial releases of foxes back into the wild.
  • All released island foxes on the northern islands have been radio collared. The radio collars enable biologists to monitor the foxes’ activity and determine their survival.
  • A program of humanely capturing golden eagles is ongoing. Approximately 40 golden eagles have been successfully captured and released in northeastern California. To date, none of the relocated eagles has returned. Currently, San Miguel and Santa Rosa islands appear to be clear of golden eagles, however some golden eagles remain on Santa Cruz island.
  • Bald eagles are being reintroduced to the northern Channel Islands. Up to 12 juveniles will be released annually on Santa Cruz from 2002 to 2006. It is hoped these bald eagles will establish territories when they reach maturity and deter golden eagles from colonizing the Channel Islands.
  • Feral pigs are being removed from Santa Cruz Island as part of a joint project conducted by the National Park Service and the Nature Conservancy.
  • Non-native plants and animals are being removed from the northern islands in an attempt to return the island habitat to its original natural ecosystem condition.

Monday, September 26, 2005

Fox Festival - Oct. 2

Join us at an UPCOMING EVENT:

Sunday, October 2, Friends of the Island Fox, Inc. will be at :

The Fall Fox Festival at the Santa Barbara Zoo

The Santa Barbara Zoo is one of the few places beyond the Channel Islands where you can see an endangered island fox. The island foxes at the Santa Barbara Zoo were the first to breed in captivity on the main land and the zoo has been very involved with the National Park Service and the Nature Conservancy regarding captive fox husbandry on the islands.

  • Come and see the island foxes enjoy some of their favorite food–insects.
  • Learn about the challenges the fox faces in the wild.
  • And have fun with fox crafts, face painting, and other activities.

What can you do to help the island fox?
  • Friends of the Island Fox will be raising money to provide funds for fox radio collars. Each island fox returned to the wild on San Miguel, Santa Rosa, and Santa Cruz Island must have a radio collar so biologists can monitor its activity and survival. Radio collars cost $250.00 each. Every little bit we raise will help to see that another island fox can be released back into the wild.
  • You also can be an ambassador. The more you know about the Channel Islands and the island fox, the more you can spread the story and help us Save The Island Fox.

All Fall Fox Festival activities are included with the price of Zoo admission.

Come out and join us Sunday, October 2 (11 AM - 3 PM) and MEET AN ISLAND FOX.

Tuesday, September 06, 2005

ABOUT THE ISLAND FOX

The island fox (Urocyon littoralis) lives on six of the eight California Channel Islands. Each island’s fox population is unique and identified as its own subspecies. For example: the foxes on San Nicholas Island have more vertebra in their tail than the other island fox subspecies.

The island fox is one of the smallest members of the dog family, or canid species, in the world. They are about the size of a housecat–weighing from four to five lbs. and standing only 12 to 13 inches high. They are 20% smaller than their closest relative, the mainland gray fox.

The tiny island fox actively seeks food during the early morning and evening, as well as at night. Their diet consists of native fruit, vegetation, mice, insects and crabs.

Male and female island foxes come together as a pair between December and January. They typically form a lifetime monogamous relationship and mate early in the spring. One to five pups are generally born between April and May. The pair raises their family together, providing a protective den, hunting for food and eventually teaching their offspring to be self-sufficient. By September, the pups are ready to be on their own and the family splits up.

In recent years, the foxes have almost disappeared on the northern islands of San Miguel, Santa Rosa and Santa Cruz. In 1994, San Miguel was home to approximately 450 foxes. By 1999, only 14 foxes remained–a 97% decline. In hopes of saving the island foxes, four of the six subspecies were listed as endangered under the U.S. Endangered Species Act in 2004–the populations on Santa Catalina Island, San Miguel Island, Santa Rosa Island and Santa Cruz Island.


CURRENT FOX STATUS

Channel Island National Park:
San Miguel Island fox - endangered
Santa Rosa Island fox - endangered
Santa Cruz Island fox - endangered
Anacapa Islands - no foxes (islands are too small and there is no fresh water)
Santa Barbara Island - no foxes (there is no fresh water)

Santa Catalina Island fox - endangered

Navy Operated Islands:
San Clemente Island fox - stable
San Nicolas Island fox - stable

WHY HAVE THE ISLAND FOXES DECLINED?

In 1994, the National Park Service recognized a large decline in island fox populations. Park biologists studied disease, predation and environmental factors, but could not explain the reason for the decline. Then a pattern began to emerge. In a two-year period, 21 out 29 dead foxes had been preyed upon. In the fall of 1998, eight foxes were radio-collared for a telemetry study to monitor their movements. In just a few months, half of these foxes were attacked. The culprit was identified by a long feather left beside a fox carcass–a golden eagle feather.

Historically, bald eagles had occupied the islands. Being territorial, they had limited the number of other large predatory birds. As predators of fish and sea birds, bald eagles did not prey on the island fox. Our national symbol disappeared on the islands in the 1950s and 60s due to the effects of DDT. Bald eagles ingested the pesticide DDT in local fish and laid eggs with very thin shells. Because the eggs broke before hatching, the bald eagles could not successfully reproduce and went extinct.

In the absence of the bald eagle, the golden eagle was attracted to the northern islands by an abundance of wild, or feral, piglets on Santa Cruz Island. The golden eagles also soon discovered the easy-to-catch island fox. The tiny foxes had never known a predator. In contrast to the mainland gray fox, the island fox may forage openly by day so is easily spotted by a hunting golden eagle. The protective cover once provided by chaparral and native plants had been eaten away by the many introduced animal species during the years of ranching on the islands. In a short time, golden eagles decimated the northern island foxes.

On Santa Catalina, the island foxes faced a different danger. An outbreak of canine distemper contracted from a local domestic dog caused their numbers to decline from 1,342 in 1994 to 165 in 2000.

Today, captive breeding and a restored native habitat are vital to saving the endangered island fox.