Friday, September 20, 2019

Fox Foto Friday - Time for Health Checks!


Across the Channel Islands, island foxes are being counted and given health checks. This island fox on Santa Cruz Island also received a refurbished radio-tracking collar funded by Friends of the Island Fox. See her as she is released.

For the next three years this radio collar will tell biologists that this island fox is up and moving around in its environment. It will also give off a mortality signal to alert biologists if something should happen to this individual island fox. Rapid response to mortalities enables a quick response to disease or threats to other island foxes. 

What are the current threats to island foxes in 2019?

Monday, September 09, 2019

FIF Research Grant to Investigate Further Into Island Fox Diet


Friends of the Island Fox is happy to announce that Juliann Schamel's research investigating island fox diet through stable isotopes in whisker samples has been chosen to receive the FIF Research Grant for 2019. 

an island fox stash of deer mice
This second year of support will enable analysis of additional data sets to identify seasonal dietary items during drought and important to successful reproduction. It has long been believed that deer mice are a vital food item during breeding and pupping season. Is it true? Does availability to a specific food source influence successful reproduction? If island foxes do not have accesses to abundant deer mice are they less successful as parents?

The grant will also expand the study to look at island fox use of marine resources. Do island foxes use marine foods during drought? If so, which island foxes are able to make use of marine resources?

Island fox whiskers provide an amazing record of what an individual island fox has been eating over 5–6 months. All food items are made up of carbon and nitrogen, but each kind of food has a different balance of elements and therefore a different signature. These individual isotope signatures are recorded in the fox's whisker. More on Schamel's initial research.

Schamel's initial whisker data set went to the lab this spring. At the Center for Stable Isotopes at the University of New Mexico, each individual whisker is divided into tiny sections and processed in a mass spectrometer.

An island fox that eats the same kind of food (all deer mice or all plant fruit) for a period of time will show an isotope graph that is fairly flat. The mixture of carbon to nitrogen will remain the same. But if an island fox changes up its diet dramatically, a spike will appear in the graph showing a change in the isotopes laid down in the whisker.


Comparing these results for known individual island foxes, living in known habitats, will provide valuable data on how sustained drought impacts island fox diet and how diet impacts their ability to survive and thrive.

The FIF Research Grant is completely funded by YOU. Without your donations to FIF this research would still be a dream. 



Donate today to support island fox conservation research.

Thank you to all of the 2019 grant applicants for sharing your research goals with FIF. There is so much more to learn about island fox health, behavior, and interactions with other species.


Applications for the 2020 Research Grant
will be available April 15, 2020
  

Friday, August 23, 2019

Fox Foto Friday - The Endangered Species Act Saved This Fox

 Just over two years ago, the Channel Island fox was removed from the Endangered Species List.

The Endangered Species Act saved this fox!

 Survival shouldn't be political.


 
Saving a species is a very complicated task, and it requires a coalition of people all working together to make it happen. 
We shouldn't abandon the Endangered Species Act.
We should embolden it, embrace it, and help the world become a better place. 


The Endangered Species Act (ESA) has provided the necessary protection and attention to help save four subspecies of Channel Island foxes from extinction.

Friday, August 02, 2019

2019 Island Fox Status Update

In 2018 most island fox populations were stable, but not without risk factors. 



As expected, high temperatures and below average rainfall in 2018 contributed to lower pup numbers and reduced adult survivorship across all islands. As first documented on Catalina Island, island fox reproduction is linked to annual rainfall. Fortunately, normal rainfall levels in 2019 should benefit all island fox populations.

In 2019 Channel Island foxes face four major threats:
  • climate change: increasing regional temperatures and decreasing annual rainfall, which reduce food resources, increase wildfire threat, and promote parasite numbers
  • biosecurity: the introduction of non-native plants, animals, and diseases
  • parasites: rising tick numbers and tick-borne diseases; increased intestinal parasites on some islands
  • reduction of management funding
The following update is drawn from FIF notes taken at the 2019 Island Fox Conservation Working Group meeting. Population numbers reported here are the official estimates from each island manager, as calculated from the fall 2018 count and reported May 21, 2019. Download the detailed 2019 Island Fox Status Update


Greatest Concern 
San Miguel Island foxes robustly recovered from 15 individuals in 2000 to over 500 by 2010 (lime-green line on graph below). As a smaller island, it will always have a smaller fox population. In 2015, however, following several years of drought, the population began declining. As of fall 2018, the population has dropped to an estimated 171 individuals (a decline of over 70%). This decline may involve several interconnected threats: climate change, biosecurity and parasites. Details regarding San Miguel will be posted in coming days.



Improved
San Nicolas Island foxes declined by 59% to 260 individuals during consecutive years of drought from 2012–2015
(pink line on graph above). The US Navy initiated native plant restoration projects in conjunction with Channel Islands Restoration. As these plants, like prickly pear cactus, mature they are providing food and habitat for island foxes and prey species. The fox population has increased to a more stable number–estimated 400 individuals. 



Stable
Santa Rosa Island foxes may have reached capacity for the island (pink line on "larger islands" graph above). Native vegetation is recovering and increasing resource options for foxes during periods of drought. No island foxes have been lost to golden eagles on this island or San Miguel since 2010. Parasites, including tick-borne disease, are a growing concern on Santa Rosa. FIF has refurbished 7 radio collars, and funded dietary research and health testing measures in 2019.


Santa Cruz Island foxes have reached capacity for their habitat. As a result the population decreased naturally during 2018 (green line on "larger islands" graph above). Parasites, especially tick-borne Lyme disease, are an increasing concern. Because the Cruz population has been stable since 2014, there is pressure to reduce funds for monitoring. This poses a potential threat because this population receives elevated contact from the outside world via island visitors. FIF has refurbished 20 radio collars for monitoring in 2019.


Santa Catalina Island foxes have also reached capacity for their habitat. In reaction to decreased rainfall, this population also declined naturally in 2018
(red line on "larger islands" graph above). Parasites, especially tick-borne Lyme disease, and biosecurity are an increasing concern for this population. Lyme disease and canine herpes virus were both introduced via human visitors and their pets. Monitoring of disease exposure is vital to this populations continued health. FIF has funded 5 new radio collars and health testing measures in 2019.

San Clemente Island foxes live on the most southern Channel Island
(blue line on "smaller islands" graph above). In 2018, they were the first population to see deaths directly attributed to high temperatures. Reduced rainfall stressed the population and eight individual island foxes are known to have perished in the heatwave between June and July of 2018. Climate change is impacting this island fox most directly. 

Download the detailed 2019 Island Fox Status Update

Friday, July 26, 2019

Fox Foto Friday - What's That Island Fox Wearing

Yes, it is a new radio-tracking collar! 


Through your generous donations, FIF was able to fund 5 new radio-tracking collars for island foxes on Catalina Island. 

Catalina Island fox receives vaccination during health check
These new collars will be placed on island foxes during this summer/fall annual counting and health checks.

Are you keeping count? We are:
Our goal is to fund 8 more $220 refurbished collars for Santa Rosa/ San Miguel in 2019. 

With your help we can meet this important need.  
Please donate today

Friday, July 19, 2019

Bald Eagles Thriving and Maintaining Island Balance for Island Foxes

Across the Channel Islands, 2019 has been the best year for bald eagle reproduction since recovery efforts began 35 years ago. This spring 24 bald eagle chicks successfully fledged from nests. (That means they survived to fly.)

According to a press release from Channel Islands National Park: "This year there were 19 breeding bald eagle pairs on the Channel Islands producing 24 chicks, including 10 on Santa Cruz Island, 9 on Santa Catalina Island, two each on Anacapa and San Clemente Islands, and one on Santa Rosa Island."


Orange wing-tags mark Catalina-hatched bald eagles
Bald eagles are a vital part of the Channel Island ecosystem. As fishing eagles, they prey primarily on fish and other birds, as well as consuming carrion. Bald eagles do not typically eat mammal prey and therefore are not usually a threat to island foxes.

On occasion island foxes climb up into bald eagle nests. For the most part the foxes act as a clean-up crew picking up tidbits of food left behind by eagle chicks. Eaglets are typically either protected by a parent when very young or too large for island foxes to prey upon.

blue wing-tags mark no. island eagles
Bald eagles therefore help transfer vital nutrients from the marine environment up onto the island. They help provide marine resources to island foxes, deer mice, and the island ecosystem. Nitrogen and calcium from fish are dropped on the land or eaten and deposited via scat. Marine resources can then help to fertilize island plants.  


Island foxes and bald eagles lived in balance on the Channel Islands for thousands of years. The oldest bald eagle fossils found in Southern California are 35,000 yrs old and from the La Brea Tar Pits. Bald eagles declined between 1945 and 1960 because of the insecticide DDT which had been introduced by people into the surrounding marine environment. DDT and bald eagle.



Bald eagles historically kept golden eagles from colonizing the Channel Islands and, in doing so, protected the island fox. Though they are both called "eagles," bald eagles (Haliaeetus leucocephalus) and golden eagles (Aquila chrysaetos) are not closely related. They come from two distinct evolutionary branches of predatory birds that separated and became competitors more than 12 million years ago. (By comparison, humans and chimpanzees diverged from a common ancestor just 7 million years ago.)

Golden eagles are mammal predators; they specialize in hunting small mammals about the size of a football (rabbits, ground squirrels, deer fawns, marmot, etc.) . Golden eagles hunt island foxes. They also eat carrion. Because both species will eat something that is already dead, they are known to take food from each other. There have been accounts of a bald eagle taking a dead island fox body from a golden eagle.


These two large birds have evolved to specialize in different food, but they compete for territory and nesting sites. Around the world fishing eagles and mammal-eating eagles are in competition with each other. You might think of them like dogs and cats–they share an ancestor, both are predators, but they have different specializations. They put up with each other at times, they will steal food from each, and in a confined space, like the islands, they just don't get along.

Though both bald and golden eagles are similar in size, resident bald eagles on the islands are frequently in mated pairs. Golden eagles encountering the islands are typically migrating individuals. This two-on-one situation gives bald eagles the upper hand.

When the Channel Islands' bald eagle population is thriving, there is no room for golden eagles and the habitat is safer for island foxes. Check out live bald eagle nest cams on the islands: http://www.iws.org/livecams.html

Friday, July 12, 2019

Foxes on Santa Cruz Island are Wearing FIF Collars


This island fox was captured and counted this week on Santa Cruz Island. 

She received a health check and her radio-tracking collar was replaced with a newly refurbished collar. Her old collar will come off and be eligible for refurbishing. 



Earlier this year, 20 radio collars from Santa Cruz Island were sent in for refurbishing and funded by FIF.

In just a few minutes this little fox was released back into the wild. Her refurbished radio collar has a battery that will last 2-3 years.


Her microchip enables biologists to identify her as a specific individual. If she is caught again this summer, the microchip reader will quickly identify her so that she can be released immediately without being handled.

Your donation of $220 would recycle her used radio collar to be placed on another island fox.

Saturday, July 06, 2019

Research Grant Deadline - July 12, 2019


The more we know about island foxes, the better we can play a positive role in their continued survival.

Friends of the Island Fox is accepting proposals for research projects that improve our scientific understanding of island foxes. Grant funding up to $5,000 is available.

The deadline for this year's applications is July 12, 2019.



Friends of the Island Fox Funded Research


Other Researchers:

We hope you are noticing that island fox research is filled with innovative women.


For other research regarding island foxes: 

Wednesday, July 03, 2019

Fox Foto Friday - Radio Collars Going On Island Foxes

photo courtesy of M. Navarro, CINP
Island foxes on Santa Cruz Island are receiving health checks and being fitted with newly refurbished radio tracking collars RIGHT NOW!

You refurbished these radio collars and today they are going on island foxes.

Tuesday, June 25, 2019

More Radio Collars for Island Foxes !


This island fox is smiling because it is wearing a newly refurbished radio collar. More about M152

Two things happened this week:
  • 7 newly refurbished radio collars arrived at Channel Islands National Park to be deployed on San Miguel and Santa Rosa Island foxes
  • FIF funded our 27th radio collar this year!

Twenty refurbished radio collars went to Santa Cruz Island in May to be fitted on island foxes this summer. 

You helped fund these radio collars to monitor island fox health and welfare

But we aren't done yet. 

Health checks and annual counting are starting across the islands. This is when old damaged radio collars are removed and replaced with new or refurbished radio collars. 

 


FIF is hoping to fund:

  • 5 more $350 new collar
  • 13 more $220 refurbished collars 

We know we can do this with YOUR HELP!


The time to radio collar island foxes is right NOW! 
Please DONATE TODAY