Island Fox Whiskers Go to the Lab

Schamel with island fox pup

FIF Research Grant recipient Juliann Schamel has been collecting island fox whiskers to study the diet of island foxes through stable isotope analysis. Her research project is in conjunction with Dr. Seth Newsome and the Center for Stable Isotopes at the University of New Mexico.

Juliann says "Once I learned how stable isotope ecology works and what we could learn about island fox ecology from this method...I was hooked. The invisible chemical world can reveal fascinating connections within food webs and beyond." More on stable isotopes

"This year, with the support of Friends of the Island Fox and [another conservation fund], we are able to investigate a variety of conservation-geared questions about island fox diet on San Miguel and Santa Rosa Islands. We are looking into how diet differs among habitats on the islands, among demographic groups, and between island fox and island skunk. We are also assessing if and how fox diet has changed over time (2010–present) in response to things like density changes in the fox population and rainfall (drought conditions). This last question may have important implications for the ecology of the acanthocephalan worm, a novel parasite that appeared in the San Miguel Island fox in 2012 (at the beginning of the drought) and has spread through the fox population."

The spiny-headed worm, a species of Acanthocephala, has been implicated in the low population numbers on San Miguel in recent years. Parasite threatening San Miguel Island Fox.

"By using whisker samples that are linked to a known individual with a known history within the island fox monitoring program," Schamel says, "we are able to track the diet of individuals over time to see if and how their diet may have fluctuated during the drought or as they moved to a new habitat."

A number of whisker specimens were collected this winter, including in the beach/dune habitat on Miguel and Rosa where island foxes are not typically counted. This will provide data on dietary resources in the marine adjacent habitat that has not been collected before. Schamel says "I am very excited to run these samples!"

Collected whisker samples are sorted, inventoried, and cataloged. Once they are cleaned, rinsed, and dried, each individual whisker is placed in vial.

Newsome and his lab manager at UNM use a razor and tweezers to divide each whisker into sub-samples: 0.2mg (weighed precisely with a micro-scale).

Schamel explains these sub-samples are fed into "the mass spectrometer, which consumes the samples and spits out data on carbon and nitrogen isotope ratios." The ratios are compared to a library of food resources and their known isotope ratios. "The FIF funding is actually paying the mass spectrometer for its time."

Schamel in the field on Santa Rosa Island.

So far ~100 island fox samples from Santa Rosa have been analyzed from a variety of habitats. In addition ~200 island fox whisker samples from San Miguel have been analyzed from 2010–2012, before the drought. Schamel will be at UNM this spring working on samples from 2014–2016. "There are many samples from the same individuals across this time frame, which will be exciting to see!"

Juliann Schamel hopes to present preliminary data at the 2019 Island Fox Conservation Working Group Meeting in May. 

Research like Juliann Schamel's is vital to understanding island fox health and long-term survival.  This research is only possible with donations from people like you.

Applications for the 2019 Friends of the Island Fox Research Grant will be available on islandfox.org on April 15, 2019.

Fox Foto Friday - Island Foxes in the Wild

an island fox during March on Santa Cruz

It's hard for people to believe that you can easily see an island fox in the wild on Santa Cruz Island. This island fox was walking across the dirt road near the visitor center. It was happy to give us time to take its photo.

The unique relationship between island foxes and people began around 9,000 years ago. The Chumash and other native peoples living on the islands regarded the island fox as an important neighbor. They did not hunt the island fox or confine it as a pet.

People are surprised when they view wild island foxes going about their daily lives with little regard for the human visitors. Maintaining this relationship means respecting the island fox and its right to live safe from threat or interference on its island home.

When Visiting Island Foxes
More on Santa Cruz Island 

Island Journal - A Visit to San Miguel Island

A visit to San Miguel Island is a rare opportunity. Island foxes are few and the land is windswept. Experience a firsthand trip to this remote Channel Island.
 

Island Journal - San Miguel Island 

San Miguel Island lies at the top of the Southern California Bight, 26 miles from Point Conception. The western most of the Channel Islands, San Miguel receives the full force of the cold California current sweeping past its shores.

Recently, I went on a rarely offered day trip to San Miguel to observe firsthand how the island is recovering from years of ranching and to get a feeling of what island life must endure to survive there. 

After a night of light rain and distant thunder, the morning was overcast, but dry. On the boat trip out, the winds were light as was the swell.  The crossing was direct to San Miguel, approximately a 3-hour trip. About an hour out of Ventura, we spotted the blow of a Humpback whale.  The Islander Packers' boat took time to observe the mighty cetacean feeding in the channel.  A few minutes later, we observed 2 more blows further out.

Santa Cruz Island and Santa Rosa Island slowly passed by on our port side. Eventually, San Miguel came into view. 
 
There is no pier on San Miguel which means we landed by skiff. It's common to have large breakers at the beach on Miguel, which can easily swamp a skiff. Fortunately, the seas remained uncharacteristically calm. We arrived on schedule at 11:15 with 110 people on-board and 2 skiffs. Each skiff  holds 6 passengers. It took approximately 30 minutes to get everyone ashore. Once on the island we had  the mandatory island briefing by the National Park Service (NPS) naturalist.

San Miguel island is owned by the US Navy and managed by the NPS.  During WWII and through to the 1970s, San Miguel was used as a Navy bombing range. To protect visitors from any hazards that might still exist (the Navy did a complete survey in 2016 and found no unexploded ordnance), and to protect the natural resources, visitors must hike in escorted groups. However, you can freely explore the mile-long beach at Cuyler Harbor and hike up to the nearby ranger station and campground. 

coreopsis

To access the island interior, we hiked from the beach up the steep Nidever Canyon for approximately a half mile, gaining 600 feet in the process. The canyon is a great example of how the island is recovering. There is an incredible display of native vegetation; very healthy coastal sagebrush and coastal bluff scrub plant communities with coreopsis, buckwheat, and dudleya. Once on top, we were afforded terrific views of Cuyler Harbor. 

Our instructions were to be back on the beach by 2:30 to begin the skiffing process back to the boat for a 3:30 departure back to Ventura, which didn’t leave much time for exploring. I decided to check out the Cabrillo Monument and wander near the ranger station.

At the ranger station, I ran into one of the fox biologists that I know, so wandering became gabbing about fox whiskers and how ice plant travels the digestive system of the fox much like celery travels ours. Perhaps TMI, but hey...that’s what we talk about and that’s one way information gets passed on.

Talking scat passes the time quickly and I had to head back to the beach. On the beach, a juvenile elephant seal was thermoregulating. They're one of the pinniped species which call San Miguel Island home.

The route back to Ventura Harbor took us along the north side of Santa Rosa and Santa Cruz Islands with a stop in Painted Cave, one of the largest sea caves in the world. The winds remained light and sea was like glass.

We were treated to numerous pods of common dolphins, numbering in the thousands, as well as two minke whales, the smallest of the great whales.

We also spotted the same humpback whale, very close to where we spotted it in the morning. (Humpbacks can be identified by the markings on their tail flukes). The Santa Barbara channel did not disappoint! 

No fox sightings to report, but I did see the tell-tale signs of their presence, chiefly scat, littered about in typical fox fashion. 

The day to San Miguel didn’t become the island exploration I first believed it would, but instead became a time to develop a deeper appreciation for the whole ecosystem that encompasses the Channel Islands. An ecosystem where the tiniest zooplankton feeds the mightiest whales. An ecosystem where man’s impact can have a profound negative impact or bring a species back from the brink of extinction. - Mike Watling, FIF Advisory Board

Tracking Island Foxes with Mike 

More on San Miguel Island 

Video from San Miguel Island  by the fox biologist Mike mentions

More on the Whisker Research and Scat

Fox Foto Friday - Spot An Island Fox?

Island foxes are rare creatures, yet sometimes they show up in unexpected places!

Take a second look, this island fox is on the calf of a devoted island fox supporter. It even has accurate island fox tracks. Tracking An Island Fox

We love art with island foxes. Check out:

island fox sculpture and carving 
Island Fox and the Art of an Ecosystem - graphite
student art project - felt
student collage and conservation projects

How will you show your support for island foxes?