Friday, February 23, 2024

Injured Island Fox Pup Gets Second Chance

 You can help this young island fox

Friends of the Island Fox is raising funds to pay for her orthopedic surgery

During the annual fall 2023 counting and island fox health checks on San Nicolas Island, biologists discovered this female pup with a recently injured right hind leg. The bones just above her foot, the metatarsal bones, had been fractured and the wound was open.

The injury was too severe for treatment on the remote Navy island. According to our friends with the U.S. Navy and the Santa Barbara Zoo: "The cause of the injury could not be determined but her chance for survival without intervention was minimal due [to] the risk of infection and septicemia posed by the open fracture. Releasing her without treatment with such an injury was determined to be both inhumane and life threatening."

island fox in the wild on Santa Cruz Island

Removing an island fox from the island where it lives is a big decision. Having evolved in isolation on their specific islands, once an island fox leaves an island it can not return. The biosecurity risk of introducing disease from the mainland to the wild population is too great.

The young fox was just old enough to be dispersing from her parents. With treatment and several months of observed convalescence, she had a good chance for full recovery. The cost of treatment, however, was being removed from the wild for the rest of her life.


The California Department of Fish and Wildlife (CDFW) gave special authorization to transport the state-protected species off of the island and off of the Navy's federal lands into state jurisdiction. She was flown off of San Nicolas Island and transferred to the Santa Barbara Zoo, which has "extensive experience in caring for orphaned and injured island foxes." A pair of brother San Clemente Island foxes who were abandoned by their parents during a drought year, currently live at the Santa Barbara Zoo. (Lewis and Clark)

In consultation with Dr. Steve Klause, a veterinary orthopedic surgeon, the Santa Barbara Zoo veterinary team initiated a conservative treatment plan. While the little fox responded well, the fracture did not initially heal as hoped. 

The Zoo team reached out to Friends of the Island Fox. The little female island fox needed special orthopedic surgical repair for internal fixation of the fracture. Could we help with some of the unexpected costs? 

FIF determined to raise the $1,900 needed.

On December 16, 2023, the little fox had her surgery and Dr. Julie Barnes Vice-President of Animal Care and Health tells us, she is doing well. The island fox still has several months of recuperation before she is fully healed. The Santa Barbara Zoo says "Once fully recovered, the fox will be transferred to a permanent home ... at an Association of Zoos and Aquariums (AZA) accredited facility where she will serve as an ambassador for the species - the first known San Nicolas Island fox to do so!"

Protecting island foxes is a community effort and saving this individual island fox is no different. People from the U.S. Navy, Santa Barbara Zoo, specialist veterinarians, and FIF are all investing in the future of this island fox.

You can HELP Too! 

Join our list of donors supporting this island fox

  • Recycling for Island Foxes and the Planet: $200
  • school children in Thousand Oaks, CA: $300+
  • FIF Instagram followers: $100
  • FIF "X" followers, including in Japan: $350
  • FIF returning donors: $435

Thursday, January 25, 2024

Unexpected Creatures During Island Fox Counting - Part 4

Welcome guest blogger Jessica Sanchez, wildlife veterinarian and FIF Board Member. She's explained how island foxes are captured annually in Part 1, shown how a fox's body condition is evaluated in Part 2, and demonstrated health procedures preformed on island foxes during an annual health check in Part 3. As she explains, she might be out capturing island foxes, but they aren't the only animals she encounters.

We also catch island spotted skunks, although this has become rarer in recent years.

You know you have caught a skunk even before you get to the trap because...

  1. of the smell
  2. they ball up all the grass and vegetation in the trap to make a cozy little nest for themselves

If you're lucky, they will still be asleep in this nest when you approach the trap the next morning. All of this gives you time to pause and carefully plan your approach to getting them out of the humane box trap. 

Skunks also get a microchip for identification and we take a tiny 2–3mm biopsy of the ear, with a special cartilage snip device, for genetic testing. Then they receive a thorough exam. (similar to island foxes) We try to handle the little skunks carefully so they don't spray us–this is for our benefit and theirs as it can take up to a couple of weeks for skunks to regenerate their spray and they need it to defend themselves. 

Currently, island spotted skunks are not vaccinated, though researchers are investigating options to potentially do so in the future.

Island spotted skunks aren't the only surprise that might be found in a box trap set out for island foxes. See what else Sanchez has found:

An island scrub-jay!

The final steps of a long day catching island foxes are to wash off any skunk spray and/or fleas, check yourself for ticks, enjoy a beautiful sunset, and get a good night's sleep before doing it again the next day! - Jessica Sanchez

Part 1 - capturing island foxes

Part 2 - Health Check: body condition

Part 3 - Health Check: veterinary procedures


Monday, January 22, 2024

Island Fox Gets a Health Check - Part 3

Welcome guest blogger Jessica Sanchez, wildlife veterinarian and FIF Board Member. She's explained how island foxes are captured annually in Part 1 and shown how a fox's body condition is evaluated in Part 2. But an island fox health check includes additional health measures.

We check the foxes for ectoparasites such as ticks, fleas, mites, and lice. We comb their fur to find fleas, and pay special attention to their ears, armpits, and belly area–where lice and ticks are often found. 

Ticks are collected so we can identify the species and test them for viruses or bacteria they might be carrying. Since ticks can feed on multiple hosts in their lifetime, testing the ticks tells us about what diseases the island spotted skunks, deermice, and other island species might be exposed to as well. 



We take a look in the fox's ears using an otoscope, just like the doctor uses to examine your ear canal. On Santa Catalina Island, where ear mites introduced by feral cats have been associated with ear tumors, foxes are treated with a topical medication to kill ear mites and reduce inflammation in the ear canal.

We collect blood from the jugular vein. This is used to test for exposure to disease, genetic analyses, and to look at other health parameters like liver and kidney function.

One of the most important steps is to administer vaccinations. A subset of the population is vaccinated every year for rabies and canine distemper virus. Neither disease is currently found on the Channel Islands, but we vaccinate as a preventative measure after the Santa Catalina Island foxes almost went extinct due to the introduction of canine distemper in 1999–2000. Vaccinations ensure that if there is ever an outbreak of either disease, at least the vaccinated foxes will survive to repopulate the island. (FIF's efforts to provide vaccine for island foxes in 2023)

A subset of foxes also gets radio collared. 


These collars are small, less than 5% of their body weight, and do not interfere with the foxes going about their daily life. Collars serve multiple purposes, allowing us to track the size and location of home ranges, monitor survival, and find dead animals quickly so their carcasses can be sent for necropsy ASAP to identify the cause of death. 

Most of the radio collared foxes are unvaccinated "sentinels," meaning if a disease outbreak occurs, they are not protected and may get sick, but their deaths will be detected via the change in their collar signal so we can recover the bodies for necropsy. Without collared animals, we would not know foxes were dying and would not be able to find the carcasses to get more information about the cause. Monitoring mortalities also gives us information on trends in other causes of death, such as internal parasites or being hit by cars, so we can address those threats as well.

Foxes are released after their workups and immediately run off! - Jessica Sanchez


In Part 4, Jessica details what happens when an island spotted skunk is unexpectedly caught during island fox health checks.

Friday, January 19, 2024

An Island Fox Gets a Health Check - Part 2

Welcome guest blogger Jessica Sanchez, wildlife veterinarian and FIF Board Member. In Part 1, she explained how island foxes are captured annually. Now, she'll take us through an island fox health check.

As biologists and veterinarians, we carefully remove the fox from the box trap, being sure not to get their tail caught in the door!

Island foxes are blindfolded to help keep them calm and reduce stress. Foxes do not have any natural predators on the Channel Islands so they are very brave, but they can still be stressed from handling by humans. Exams are quick and we do our best to be quiet and efficient. Island foxes are not sedated, so they can be released immediately and return to life as normal ASAP.

The health exam begins with an examination of teeth.

We open their mouths very gently so we can see the upper premolars. The wear on these teeth allows us to classify each animal into an "age class." Age classes range from 0 (pups born that year) to 4 (very old foxes with worn teeth). The pups also have serration on their incisors that have not yet worn smooth. Although age classes are not an exact age–and can vary by island, diet, and habitat (rougher food and sand wear teeth faster)–they give us a semi-standardized guide for assessing how old the population is overall. (more on using teeth to age island foxes)

We can also identify the pups of the year (less than a year old) by their appearance. They start out darkly colored and slowly transition to their adult gray/rufous/white. By the time we catch them during the summer/fall season, they look like mini-adults but with a rounder, fluffier shape.

Reproduction can be assessed in the females by examining their abdomens. A female who has not had pups that year will have white fur on her belly, with no mammary/nipple development (left, below). A female nursing pups will have the hair licked away from her nipples, the surrounding hair will be stained red from the saliva of the puppies, and her mammary tissue will be large and well developed from producing milk (right, below).

We do a thorough exam, assessing body condition and checking for any injuries. We check each foot to make sure they have no injuries to their claws, which are semi-retractable. Island foxes and grey foxes are unique among canids in that they can rotate their wrists, allowing them to grip and climb trees. (more on the island fox's ancestor, the grey fox)

Foxes often have grass awns or other debris stuck in their eyes, so we clean these out and remove any gunk that has accumulated. - Jessica Sanchez

In Health Check Part 3 - Jessica will detail the specific health measures taken for island foxes.

Part 4 - Other species encountered during health checks

Tuesday, January 16, 2024

How Do Biologists Capture Island Foxes?

Meet guest blogger, FIF Board Member, Jessica Sanchez. 

Sanchez is a wildlife veterinarian and epidemiologist who's been working with Channel Island foxes since 2006. She started her career managing the captive breeding and wild fox monitoring program on Santa Cruz Island. For her master's degree, she researched social interactions among island foxes, and modeled vaccination and monitoring methods to prevent and detect disease outbreaks. She is currently a consulting veterinarian for island foxes across the Channel Islands, providing medical care and advising on biosecurity and fox health research.

Every year, island managers and biologists conduct island-wide capture of wild island foxes to monitor the population size, reproduction, and health of individuals. This is done using the same locations every year, so direct comparisons can be made and trends identified. (counting island foxes)

The first step is finding a safe location to place a box trap–somewhere with flat ground, so it won't roll. It has to be out of the direct sun and wind, away from water with no risk of flooding, and where we can use vegetation to cover and disguise the capture device.


We capture foxes using wire, humane, live box traps; the very same ones used to capture feral cats. There is a "treadle plate" at the back that is attached to the door with a stiff wire. When the animal steps on the treadle, the door closes behind them.

We disguise the wire bottom by covering it lightly with grass or other vegetation. This also provides a comfortable bed for the fox to spend the night. We attract the fox with a small cup of fox-safe food at the very back, past the treadle. The fox must enter far enough to trigger the door and close it behind itself. An aromatic scent is also spread on a branch above the box trap–this scent travels longer distances than the smell of the food and attracts the fox to the area.

We cover the box trap with vegetation so the island fox is shaded and protected from any other animals that might come poking around. Then, we leave it overnight and return to check it first thing in the morning.

Sometimes, animals will try to get to the bait without going inside. This trap was disturbed by ravens! Ravens are extremely smart and will learn that the brightly colored "flagging" we put on trees to mark locations means there is an easy meal nearby.

If a fox is in the box trap, we first weigh both the trap and the fox. Once the fox is released, we subtract the weight of just the trap to calculate the fox's weight. An adult island fox will weigh between 1.5–3 kg, or 3–6 lbs, with foxes being slightly different sizes on different islands (largest on Santa Catalina, smallest on Santa Cruz).

We carefully remove the fox from the trap, being sure not to get their tail caught in the door!

The first thing we do once we have the fox in hand is scan it for a microchip tag, just like the ones used in dogs and cats. This tells us that the fox has been previously caught. The microchips are small implants, the size of a grain of rice, and are inserted under the skin near the shoulder blades using a needle.

The microchip provides lifelong identification of an individual so we can track its history–the locations it was captured, its age, any injuries, whether it had offspring, vaccines administered, any blood test results, and radio-collar frequencies.  - Jessica Sanchez

See F257's multi-year story.

The microchip can also alert the biologist that the captured fox has already had a health check that year. If so, it is immediately released.


If not, the island fox will receive a full health check. Follow as Jessica provides an island fox with a Health Check Part 2 - body condition. 

Health Check Part 3 - Preventative care 

Other species encountered during health checks

Saturday, December 16, 2023

Fox Foto Friday - Radio Collars on San Miguel Island Foxes

 Look who's getting radio tracking collars!

Island foxes born on San Miguel Island in April of 2023 are now adults and large enough to wear radio collars. Three were fitted with radio collars this week. The mask helps the island fox remain calm while the collar is being fitted.

Channel Island National Park biologists report this year's young adults are looking very healthy.

Watch them for yourself as they are released with their new radio collars.


Your donations to Friends of the Island Fox 

help to fund radio collars, vaccinations, and research 

into island fox health and behavior

Tuesday, November 28, 2023

Date With A Fox - Tim Coonan, Biologist

 Join Friends of the Island Fox for a Virtual Event !

"Date with a Fox" 

with guest Tim Coonan

Tuesday, December 5 

6:30 - 7:30 pm Pacific Time on Zoom

Tim Coonan is the retired Senior Biologist for Channel Islands National Park. He documented the mysterious decline of island foxes across the northern Channel Islands and uncovered that golden eagles had colonized the islands and were unexpectedly preying on island foxes. 

How were the decisions made to bring island foxes into captive breeding? What steps had to be taken to restore the ecosystem so that island foxes could return into the wild and recover their populations? Tim Coonan was there when only 15 individual island foxes remained on San Miguel Island and four populations were listed as Endangered Species. 

He released the last captive island foxes back into the wild and is the co-author of "Decline and Recovery of the Island Fox." 

Join FIF for an intimate conversation with Tim Coonan and a chance to ask your questions about island foxes.


Monday, November 13, 2023

She's Back! F257 - an Island Fox with a Story

F257 was true to form in 2023. She was captured during island-wide counting on Santa Rosa Island for the fifth year in a row!

This charismatic female island fox was first captured and radio-collared in the fall of 2019 as a pup of that year. She was collared in the territory where she was born and there were thoughts she might provide additional data on how far female offspring disperse from their parents' territory.


She didn't go anywhere. F257 remained in the coastal plain of her childhood. She has been captured each year, not only in the same area, but in exactly the same location. A highly unusual occurrence.


Health checks in 2020, 2021, and 2022 found F257 healthy even during years of drought. She even was videoed after receiving her new radio collar. But physical evidence revealed that this healthy female island fox had not become a mother. Island foxes typically have pups in their second year, but they can breed before they are a year old if resources are available. During the 2021–22 drought years, most female island foxes did not breed.

This year F257 approached breeding season as a middle-aged fox–4 years old.

The rainy winter suggested a boom of resources for island foxes. We all waited to see what would happen with F257.

When she was captured in September, F257 showed evidence of nursing pups. 

Island fox females who have NOT been nursing have white bellies.

Females that have been nursing have pink bellies.

F257 has added her genes to the population of island foxes on Santa Rosa Island. We hope she continues to thrive and tell her story.

More on island fox reproduction.

Monday, November 06, 2023

FIF 2023 Research Grant to Help Count Island Spotted Skunks

Friends of the Island Fox received a record number of grant applications this year. Funds were awarded to two projects. Today we highlight:

Desirae Thomaier a masters student in Biological Sciences at Cal Poly San Luis Obispo. 


Island foxes share their habitat with island spotted skunks on Santa Cruz and Santa Rosa Islands. When island fox numbers declined due to golden eagles, island spotted skunk numbers increased dramatically. As island fox populations recovered, skunk numbers appeared to decline. 

While some researchers have attempted to follow island spotted skunks with radio-tracking collars, the spotted skunks small size and seasonal weight fluctuations make it difficult to effectively use radio collars. Prior studies recommended wildlife field cameras as a way to potentially quantify the number of island spotted skunks on each island.

Thomaier's project–Occupancy modeling of Island Spotted Skunks on Santa Rosa and Santa Cruz Islands–will deploy 60 field cameras across each island for a full year.

Hopefully, this effort will provide a better accounting of island spotted skunks numbers and how they are "responding to very high fox abundance."

Island spotted skunks are nocturnal. Interactions between island foxes and island spotted skunks under the cover of darkness. Thomaier's cameras may also uncover additional information about the interactions between these two island carnivores.

The series of three photos below were taken over the course of 8 minutes.

One spotted skunk followed less than a minute later by an island fox.

Followed 7 minutes later by two island spotted skunks.

One skunk is in the upper left corner with the second skunk right on its heels. (photos courtesy of Channel Islands National Park)

What is the story here? We really don't know. Hopefully, Thomaier's research project will help provide a more accurate count of island spotted skunk populations and shine a light on the complicated relationship between these two island predators.

Island spotted skunks may deserve separate species status. FIF Research Grant 2022 recipient Julia Owen will be presenting at the California Island Symposium this week in Ventura.

Tuesday, October 17, 2023


Friends of the Island Fox will be at the 

P-22 Day Festival 

Sunday October 22 at Griffith Park

Come by our booth and see if you can detect what island foxes have been eating.


We'll also be unveiling our new Island Fox Science shirt -

It's Science, for Fox Sake!

- to raise funds for island fox scientific research. 

Come out to celebrate the life of mountain lion P-22 and support California wildlife at the P-22 Day Festival.