Across the San Joaquin Valley, small, tan foxes roam the arid landscape. They are built for this challenging environment. Their oversized ears help dissipate body heat and small paws can run swiftly over the hot dirt. But the already rare fox, listed as an endangered species, is seeing sharp population declines due to an epidemic of mange.
“San Joaquin kit foxes live in small, humid dens with their families. When one kit fox brings mange into the den, they all get it, and unfortunately, some die from the disease,” said My Nguyen, senior wildlife biologist in the U.S. Fish and Wildlife Service’s Sacramento Field Office.
Sarcoptic mange, the type of mange that is impacting foxes, is caused by mites that burrow under the skin, causing intense itching, hair loss, skin thickening and scabs. The scabs can serve as a location for secondary bacterial skin infections that can ultimately result in death. While great efforts have been made over the past few years to treat infected foxes and slow the spread of mites with treatment collars, the foxes continue to contract the disease.
However, two grants announced by the Bureau of Reclamation and the U.S. Fish and Wildlife Service will fund research that aims to find solutions to the epidemic. A grant provided to the Endangered Species Recovery Program of California State University Stanislaus will support data collection on the extent of the spread of mange and work to develop a strategy that treats and controls the spread of mange among kit foxes. The study will also look at how kit foxes are exposed to the disease. The other study, conducted by the University of California at Davis, will use fox scat to detect mange-causing mites and learn more about population density and diet among the foxes.
“When we combine the findings generated by these two studies, we’ll have a better understanding of how the disease is contracted, how many foxes are infected, and how we can best control the spread of disease to give the species a chance at rebounding,” said Nguyen.
Every two years, Reclamation and the Service issue a call for projects that can help endangered species impacted by the Central Valley Project, the extensive network of federally-managed canals and reservoirs that deliver water from Shasta Reservoir in the northern part of California to the southern San Joaquin Valley. Selected projects are funded through the Central Valley Project Conservation Program and the Central Valley Project Improvement Act Habitat Restoration Program. While some projects focus on research that can help listed species recover, other projects conserve land and restore habitat that the listed species depend on.
“We receive many high-quality proposals from partners for work that could conserve and improve habitats or conduct important research that will help endangered species. Given limited program funding, it’s always a challenge to choose among the proposals for the grants to award,” said Daniel Strait, natural resource specialist and lead for the grants at the Bureau of Reclamation.
Most selected projects are based in the San Joaquin Valley, but the funding supports any species impacted within the CVP area. For this grant cycle, the Service will manage research-based grant projects while Reclamation will manage grants for land restoration and land conservation projects. Projects selected this year will receive a total of $4.7 million between now and the end of 2024.
The agencies also selected a third research project to fund that is focused on determining the distribution and genetic diversity of Santa Clara Valley dudleya, an endangered plant that is only found in Santa Clara County, California. The study will develop a seed collection protocol and pilot a seeding effort in the hope of increasing the plant population in suitable habitats.
“This project builds on several years of research that has shed a lot of light on the habitat that the plant thrives in. This project will provide the foundation for potential seeding projects in the future with the goal of recovering the plant,” said Nguyen.
In addition to providing grants for research, the agencies announced that they will provide three grants that will go toward land protection efforts and two grants for habitat restoration projects. Habitat restoration projects funded by the grants will restore native grasslands in the San Joaquin Valley for blunt-nosed leopard lizards andhabitat in Butte County for yellow-billed cuckoos. Grant funding will also go to supporting the finalization of conservation easements that will help the recovery of vernal pool species in Merced County, the large-flowered fiddleneck in Alameda County and multiple listed species in the San Joaquin Valley.
“Conserving and restoring these habitats will contribute greatly toward meeting recovery goals for the species,” said Strait.
Overall, habitat restoration, habitat protection and research are three key components to helping California’s endangered species recover.
“These grants have helped dozens of species over the years,” said Nguyen.