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Monday, April 14, 2014

The Science of Counting Island Foxes

courtesy of National Park Service
In 2000 when there were only 15 island foxes surviving in captive breeding pens on San Miguel, you could count them easily on your fingers.

Today all Channel Island foxes across the six islands where they live are back in the wild. (A few rescued individuals from San Clemente Island can be seen in mainland zoos.) The recovery of the endangered island fox on San Miguel, Santa Rosa, Santa Cruz and Santa Catalina Islands has been record-breaking and the days of counting all of the physical island foxes are long gone.

courtesy of National Park Service

The process of counting foxes on each island begins in the fall with special capture cages.

These cages are set up either at the cross sections of grids or along a string depending on the island and its topography (More on strings and grids)

Cages in an area are set out over the course of a specific number of nights and checked each morning. On Catalina, each string is run for four consecutive nights; after that, typically the majority of individuals would be foxes that had already been captured on previous nights. Each island fox is identifiable because it has a Passive Identification Transponder (PIT) microchip. An island fox caught for the first time receives a PIT tag. From that point on the PIT tag allows it to be recognized as a specific individual. It can take weeks for biologists to evaluate each island.

Over the course of all the capture nights, the number of individual island foxes, their gender, ages and location caught are documented. Island foxes are quite territorial, therefore it is unlikely that a fox caught in one area of the island would be found on a different area of the island during the month of counting. (If it is, that is important too.)

The data is input into a modeling program for analysis. Different programs may be used on different islands and over the years land managers may change which program they use. The modeling program calculates the density of island foxes in specific habitats across the island and estimates a total island population.

Sometimes, however, it takes a human brain to see complexity in the numbers. On two islands where recovery has been robust over the past few years, San Miguel and Santa Catalina, the estimated population numbers appear to be higher in 2013 than they were in 2012.

But observations on both islands conclude that drought may have reduced births and did cause starvation in a number of pups last summer, prior to counting. How could the population number increase while the number of surviving pups decreased significantly?

Biologists Calvin Duncan and Julie King from the Catalina Island Conservancy explain that on Catalina they caught a greater number of adult island foxes that had not been counted for a number of years. Young animals are more likely to be curious and challenged with finding food; they venture into capture cages more readily. Once an animal is in the cage, no other can be caught that night. This year, on the fourth night of capturing, they were still finding a high percentage of animals that had not been caught on previous nights.

courtesy of Kevin Schafer

The increase in the population number for Catalina is warranted because of the number of unique individual animals that were counted. But rather than an increase in the population, the number represents a refinement of the estimate toward greater accuracy.

On both San Miguel and Santa Catalina Islands, island fox numbers have surpassed historic population figures. Both islands may have reached carrying capacity, or the number of individual animals that can find the territory and food resources necessary for a healthy life. As the drought continues this summer, there may be further impacts not only on pups, but also on older individuals.

Counting island foxes provides an important picture of island fox recovery, but observations throughout the year, health checks, blood tests, data collected from radio-collared island foxes and necropsies is vitally important to understanding the whole recovery picture.

Tuesday, April 08, 2014

Studying Island Fox Blood

What is the biologist doing to that island fox?

Blood samples play an important role in not only monitoring island fox health, but also in alerting biologists to potential diseases island foxes may have been exposed to. When an animal comes in contact with a disease, their immune system creates antibodies to fight against the disease threat. 

By testing island fox blood samples for titers, levels of antibodies, biologist can determine if island foxes have encountered new disease threats. They also can tell if individuals are carrying antibodies from vaccinations at high enough levels to protect them against know diseases like rabies and distemper.  

Serology, studying blood samples, may not sound very exciting, but it is very important to the recovery of the endangered island fox. Thanks to a $2,000 grant from our friends at the Fresno Chaffee Zoo, island fox blood samples taken during annual fall health checks last fall will be examined for antibodies to various canine diseases (distemper, parvo, etc.).

Tuesday, March 18, 2014

Island Fox Ambassador Schools

FIF Educators with students
Across Santa Barbara, Ventura and Los Angeles Counties, school children play an important role in actively working to protect and save Channel Island foxes. Not only are these young people actively participating in efforts to protect an endangered species, they are becoming stakeholders in their local environment.

Island Fox Ambassadors are individuals, classes, groups, grades, or whole schools where the students have taken a special interest in island fox conservation and have participated in some way to help save endangered island foxes.

How big is a golden eagle?
  1. First, Friends of the Island Fox educators visit the school or group and provide a presentation on the island fox and why it is endangered. Programs.
  2. The young people then decide how they will contribute. Will they spread information to others, like their parents, families and friends? Will they raise funds for some aspect of island fox conservation? Will they engage in a service project on the islands?

Highlighting two 2014 Island Fox Ambassador Schools:


Canalino Elementary School 

Teachers Kathleen Tomscha and Monica Shugart led the 4th grade teachers at Canalino Elementary to become Island Fox Ambassadors in 2009. They established a successful program selling hot chocolate and popcorn at the school's Family Movie Night and over the years the students and teachers of Canalino Elementary have funded - 2 radio collars and 13 vaccinations.

This year, the 2nd grade students in four classes worked together and raised $88 to fund eight more island fox vaccinations.

They were excited to look at island fox and bald eagle biofacts-including skull replicas, pelts and radio collars.

Carpinteria Family School 

Teacher Jan Silk has encouraged her 3rd and 4th grade students to be Ambassadors since she participated in a FIF teacher workshop in 2009. This year her students made a model island fox and collected donations for the opportunity to name the fox. When Pat Meyer visited the school she reached into the container and chose the ticket with the name. Much to everyone's delight, the name was "Pat."

The students also are selling purses they have made. So far this year they have raised $120 for island fox health checks and vaccinations.

The class will be visiting Santa Cruz Island in April and participating in two service projects: removal of non-native plants and collecting data on the types of trash enticing to island foxes in the campground and public areas. Over the years Jan's classes have also funded - a "Watch for Foxes" road sign and a radio collar.

Other Ambassador Schools:

Lincoln Elementary currently working on a project.
Montecito Union Elementary, Santa Barbara - 20 vaccinations
Blackstock Middle School, Ventura - a vaccination
Santa Clara Elementary School, Los Angeles - 8 vaccinations
Buena High School Environmental Club, Ventura - radio collar
Westridge School, Pasadena - radio collar
Moorpark College Teaching Zoo, Ventura - health checks
Santa Barbara Charter School, Santa Barbara - vaccinations
St. Cyril's of Jerusalem School, Los Angeles - radio collar
Hancock Park Elementary School, Los Angeles - radio collar and enclosure improvements for the breeding facility in 2006
North Hollywood High Zoo Magnet School, Los Angeles - health check
St. Louis DeMondford High School, Santa Maria - radio collar

Wednesday, February 12, 2014

FIF Spring Trip to Santa Cruz Island

Scorpion Anchorage, Santa Cruz Island, Channel Islands National Park
Spring offers beautiful days on the Channel Islands. Ocean views are made even more thrilling when you realize someone four-footed is enjoying them too.

Santa Cruz Island fox
Under the table, a curious Channel Island fox is investigating the human visitors.

The ongoing successful recovery of the endangered island fox means there are many opportunities to see this charismatic creature in its native habitat ! 

Join Friends of the Island Fox for a day of discovery and adventure as we travel to:

Scorpion Anchorage, Santa Cruz Island
Channel Islands National Park
May 3, 2014

This half-day trip offers options on arrival time:

  • 9:30 AM: For those who would like an early start, meet us at the Channel Islands National Park Headquarters, at 1901 Spinnaker Drive, Ventura (right at the end of Spinnaker Drive, beyond Island Packers).  We will tour the Center, receive a Tidepool Talk, and have the chance to view the Park film “Treasure in the Sea.”  
  • or 11:15 AM: Check in with Friends of the Island Fox at the Island Packers’ Ventura Harbor dock, at 1691 Spinnaker Drive, Ventura, for a noon departure to Santa Cruz Island, Scorpion Anchorage.
  • 5:00 PM: Island Packers’ boat departs Santa Cruz Island, arriving in Ventura Harbor around 6:00 PM

Tickets are $65.00 per person. 
(A percentage of the fee will go to support island fox recovery efforts.)
Reservations are limited and will be provided on a first come basis. To book reservations, please download the Reservation Form.

Send the completed form with your check, made payable to the "Friends of the Island Fox" to the address on the form.  Reservations will be taken in the order received, and no reservations can be accepted without payment.

At the time of booking you will receive further details of the trip, including: maps of where to meet, what to pack, suggested clothing and other items of interest. Remember the photo at the top. Island foxes are smart and curious, food items must be secured at all times.

If you have questions, contact FIF at
or (805) 228-4123

What to remember when visiting the island fox. 

Previous trips to Santa Cruz Island:

June 2013 Trip and Items on the Beach 
May 2012 Trip 


Tuesday, January 28, 2014

Which Island Foxes Wear Radio Collars?

island fox with radio tracking collar; courtesy CIC
Island fox populations are returning to normal levels across the six California Channel Islands where this rare species lives. With hundreds of island foxes on each island, the number of radio-collared animals is limited to a representative group. Typically 40-60 individual animals wear radio-tracking collars on each island.

 Which island foxes receive radio tracking collars?

Island foxes that wear radio-tracking collars are typically younger–ages 1-4 years old. Island foxes can live 8-10 years in the wild, with rare individuals living to age 12 years. Younger animals are more likely to move across the islands as they try to find a mate and establish their territory. (Female that traveled across Catalina's isthmus

While some radio-collared island foxes are individuals with specific survival challenges (Burnie Boots and three-legged island fox), most collared island foxes act as disease and predator sentinels. If something happens to these foxes their demise is quickly brought to the biologists' attention because of the radio collar. When an island fox stops moving, even breathing, for over six-eight hours the collar signals a specific mortality signal. Using the signal, biologists can locate the island fox's body, discover the cause of death and take action. (Listen to radio signals on our Audio/Video page)

“Being able to identify the threats greatly improves our ability to understand and protect this unique species,” says Julie King, director of conservation and wildlife management for the Catalina Island Conservancy. Once the carcass is collected it is sent to the California Animal Health and Food Safety Laboratory to ascertain the exact cause of death.

Both male and female island foxes can be sentinels. These individuals are not vaccinated against the two most threatening diseases to island foxes–rabies and canine distemper. (FIF vaccination funding) 

courtesy of Jason Bean
Reading information from the radio-collars varies across the islands. On flat-terrain islands radio receiver towers pick up the signals of island foxes in their area and relay the information to a computer terminal. Mountainous terrain is more challenging; on some islands radio-collar signals are picked up from the air by small aircraft, weekly or biweekly. On other islands, biologists with hand-held antennae and a receiver locate island foxes from vehicles or on foot.

In 2014 FIF has the goal to fund our 100th radio collar. With your help we will reach that goal. 

Wednesday, January 15, 2014

Come to the Fox Festival

Where can you see island foxes and learn more about them without taking a trip to the Channel Islands?

At the...

Sunday, Feb. 16th 2014
11 AM - 3 PM

Friends of the Island Fox invites you to join us in celebrating FOXES !

There will be activities, crafts, Keeper Talks, and an opportunity to see Channel Island foxes and compare them with the Zoo's new African fennec foxes. 

What do these two species of tiny foxes have in common? Which has the bigger ears? Which eats insects?

The Santa Barbara Zoo is also home to several bald eagles. 

Come out and join the Fox Fun. Friends of the Island Fox will have a booth with current island fox information and fox related activities.

Thursday, January 09, 2014

Bald Eagle Recovery on California Channel Islands

courtesy of Peter Sharp
The return of bald eagles to the California Channel Islands has been a slow but steady effort that has aided the Channel Island fox recovery on the northern islands. A robust bald eagle population keeps away golden eagles, island fox predators.  

Island fox recovery has been incredibly rapid. More typical of efforts to save endangered species, bald eagle conservation has spread across decades: 
  • 1967 bald eagle listed as endangered species
  • 1970s bald eagles become extinct on the Channel Islands
  • 1980 - 1986: 33 young bald eagles are reintroduced to Catalina Islands 
  • 1987: eggs laid by bald eagles on Catalina Island fail to survive because of continuing high levels of DDT in marine ecosystem
  • 1989: bald eagle eggs taken from Catalina Island nests and incubated. Later hatchlings or foster chicks are returned to nests. 
  • 2000 - 2002: juvenile bald eagles reintroduced to the northern Channel Islands 
  • 2006 first chick hatched without human assistance on the Channel Islands in 50 years; female A-49
  • 2007 bald eagle eggs hatch on Catalina Island without human assistance
  • June 2007 bald eagle taken off of the Endangered Species List
  • 2012 Female A-49 nests for the first time on Santa Cruz Island, but first chick does not survive
  • 2013 MILESTONE EVENT - Female A-49 and mate become the parents of female chick A-89 the first second-generation bald eagle chick successfully fledged on the Channel Islands since the beginning of the recovery effort

According to the biologists managing the bald eagle recovery program, fifteen pairs of bald eagles attempted to nest on the Channel Islands last year. See a photo of A-89 and the full accounting of bald eagle nesting on the Channel Islands in 2013 at the Institute for Wildlife Studies.

As a large predatory bird, the bald eagle plays an important role on the California Channel Islands. For more about bald eagle recovery SEE Video: Return Flight: Restoring the Bald Eagle to the Channel Islands by the Filmmakers Collaborative 

Wednesday, December 18, 2013

Celebrating Island Foxes, Bald Eagles and the Endangered Species Act

courtesy of NPS, Island Fox Recovery Group
December 28th is the 40th Anniversary of the Endangered Species Act (ESA). This vital legislation was implemented during President Richard Nixon's administration, along with the Migratory Bird Act, the Clean Air Act and Clean Water Act. Both political parties came together to improve the environment. Forty years later, there is much to celebrate.

Channel Island foxes were faced with extinction on four islands between 1998 and 2001. In 2004, island foxes on San Miguel, Santa Rosa, Santa Cruz and Santa Catalina were granted Endangered Species status resulting in additional protection and financial support for conservation efforts.

courtesy of P. Sharp, IWS, Island Fox Recovery Group
The ESA also played a vital role in protecting the bald eagle and restoring it to the Channel Island ecosystem. The interconnection between the island fox and the bald eagle meant that the survival of the island fox was dependent on the bald eagle's recovery. The role of the bald eagle on the Channel Islands.  

Protection under the ESA and conservation efforts have helped the bald eagle return from the edge of extinction. Island foxes are similarly benefiting. In less than ten years since their listing as an endangered species, island populations have shown dramatic increases and three populations have reached recovery levels. Early reports from Santa Rosa Island this fall suggest that the island fox population on Santa Rosa is now climbing toward recovery as well.

A major factor in saving the island fox has been the collaboration between government agencies, scientists, non-profit organizations and private individuals like you. Each year representatives from all of the Channel Islands, with island foxes, meet to share information and problem solve together. 

This December as we celebrate the Endangered Species Act and the success of island fox recovery, financial support to continue the annual Island Fox Recovery Group Meeting is in jeopardy. FIF knows that nothing is more important for the future of island foxes than bringing all of the people who work with the island fox together to share information. When everyone is in the same room, we save money, time and island foxes.

Help us raise $3,000 to support the annual Island Fox Recovery Group Meeting. It is a small investment, sure to reap conservation rewards. Please donate at the "Special Funding Need" donation button on the right.  

Find out more about the Endangered Species Act

Tuesday, December 03, 2013

What Does The Fox Say?

Since a music video with singers dressed as foxes went viral, the refrain "What does the fox say?" has become a recurring question.

Well we have an answer. The island fox BARKS!

Watch the video below taken in the field by biologist Calvin Duncan on Santa Catalina Island.

Island foxes bark to declare their territory. They may be small in size, but Channel Island foxes are big in personality.

Now you know what the fox REALLY says.

Monday, November 18, 2013

Radio Collars Protect Island Foxes

courtesy of Kevin Schafer
Island foxes are making a strong recovery across the Channel Islands, but the need to monitor their populations continues.

This past year, in 2013, three radio-collared island foxes were killed by golden eagle predation. Two foxes were killed by a golden eagle on San Miguel Island and one on Santa Cruz Island. Biologists do not know if the island foxes were killed by the same golden eagle or by two different golden eagles. The distance between the islands can be easily managed by a single large eagle. However, in the past, golden eagles have often preyed on island foxes in a specific area when they have been successful.

As the populations of island foxes have increased, the cost of radio-collaring all adults has become prohibitive. Radio-tracking collars now cost $300 each. A representative number of island foxes are radio-collared on each island–approximately 5% to 11% of individual island foxes on each of the northern islands. 

golden eagle at Denali Nat'l Park, courtesy of NPS
For each radio-collared island fox killed by a golden eagle, there is the possibility of several non-collared foxes being impacted as well. Island foxes are well camouflaged for their habitat. When an island fox without a radio collar is killed by a golden eagle it is difficult to know the incident happened, little alone to find the fox's remains. 

Because radio-tracking collars give off a specific signal when a fox is no longer living, radio collars are vital tools for locating individual island foxes and responding quickly to determine why that animal has died. Island Fox CSI

On Santa Catalina Island this past year biologists were on the look out for stowaway raccoons carrying disease. But in 2013 they encountered a new invader–a northern opossum that hitchhiked on a private boat and made its way onto the island. Introduced animals pose a serious disease threat to island foxes. Canine distemper 

Radio-tracking collars are the island foxes' best defense against unexpected threats. To-date Friends of the Island Fox supporters have funded 96 radio collars. 

The Foxy Ladies of El Segundo Ladies Golf Club
$300 Helps protect island foxes. Who has funded radio-tracking collars? 

Join with other people to help fund radio collars for island foxes.