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.