Catch & Release: When to Decide if Medical Intervention is Needed During Wildlife Captures

By Jaime Rudd, WIL Scientific Aid

The Living Desert Zoo publishes an online magazine, FoxPaws. In article 7, issue 2 the zoo writes about an injured desert kit fox that WIL brought into their care last winter.

Studying wildlife on nature’s terms can be difficult. Not only can the weather and topography be uncooperative, but the study species can pose challenges as well. One challenge is deciding if intervention is necessary and appropriate if an animal is found sick or injured.

Here at the Wildlife Investigations Laboratory (WIL), we have veterinarians who can help make decisions regarding wild animal care. Deana Clifford, WIL’s non-game veterinarian, is also an epidemiologist and field biologist. With her diverse background in field studies and wildlife medicine, she is able to make important decisions while in the field or here at WIL. However, like many field biologists, she finds herself in remote areas far from home. In these situations, we rely upon local wildlife rehabilitation facilities for their time and care.

The Tennity Wildlife Hospital and Conservation Center at the Living Desert Zoo in Palm Desert has partnered with WIL to provide medical treatment for sick or injured desert kit foxes (Vulpes macrotis). The desert kit fox disease monitoring project is ongoing and began in January of 2012 in response to a canine distemper outbreak that occurred at a solar development site in eastern Riverside County. During our January 2012 capture effort, an adult male desert kit fox was suspected to have a broken jaw. The decision for intervention was made by Dr. Clifford, who quickly weighed many factors to decide if the risk associated with temporarily taking this fox out of the wild was mitigated by the benefit that would be gained from treatment.  Key considerations for her decision making included: Was the injury significant enough to affect the fox’s chance of continued survival? Could the cause of the injury be associated with our trapping efforts? Could the injury be fixed allowing the fox to return to normal?

Since this injury could definitely affect the fox’s ability to catch prey and potentially was repairable, we transported the fox to the Living Desert Zoo to confirm whether or not the jaw was broken, and if so, examine options for repair.  Living Desert veterinarian Dr. Kevin Leiske consulted Dr. Yee, a veterinary dentist at Veterinary Dental Specialists, and a treatment plan was set up to care for the young male with the intent to release him back into the wild. After approximately 7 weeks of care, the fox’s jaw had healed. Before release, zoo staff made sure that the fox was able hunt and eat whole prey. In March 2012 he was fitted with a radio collar and then taken back to the site where he was originally captured (under state department regulations, all wild mammals must be released within 3 miles of where they were found).

Not long after release, the fox’s collar went “off-air” and biologists were unable to track him. Despite an extensive ground search by California Department of Fish and Wildlife (CDFW, formerly Fish and Game),  biological monitors at the solar site, the Bureau of Land Management (BLM), and volunteers, we did not find the fox. In October 2012, CDFW took to the sky to listen for his signal, but again was unable to successfully locate this one fox.

In January 2013, our concerns were finally laid to rest when we recaptured this male fox! His jaw is a little bit crooked but he was in good body condition and weight — clearly surviving and doing well back in the wild. We also discovered that his collar had simply malfunctioned and was no longer working.  We then removed the collar and sent this fox back on his way to continue thriving in the wild.

After WIL biologists discovered that the radio collar on this desert kit fox was no longer working, it was removed. Upon his release, he offered a unique photo opportunity as he rolled around on the sand – not far from biologists! Photo courtesy of Deana Clifford.

There is always a risk when an animal has to be removed from the wild, even if it’s just for a few hours or days. Biologists understand this risk and must consider the benefits, if any, to the animal. Knowing the life-history and behavior of the study species is extremely important during the decision-making process.  In this case, a young otherwise healthy male desert kit fox was found to have a potentially life-threatening injury that could be treated with minimal human contact. If we treated his injury and successfully healed the fracture, we felt that his probability of survival was much greater than if we knowingly released him with a broken jaw.

A healed and healthy desert kit fox was recaptured this winter, one year after he was found with a broken jaw. Trained wildlife biologists are able to use physical restraint rather than chemical immobilization during desert kit fox physical exams. This allows us to quickly conduct exams and take samples without the use of drugs. In this photo CDFW volunteer biologist Teri Baker gently holds the fox while WIL veterinarian Deana Clifford  documents his uniquely new physical feature – slightly protruding lower canines.  This male fox was found to be in good weight and physical condition at the time of recapture. Photo courtesy of Deana Clifford.

WIL would like to sincerely thank Dr. Kevin Leiske, Saldy Portacio, and the rest of the wonderful staff at Living Desert Zoo for generously giving their time and providing care  to the desert kit foxes and other desert wildlife. To read more about how the Living Desert cared for this desert kit fox, go to page 4 of FoxPaws Magazine.

PLEASE NOTE: Only state and federally permitted individuals or organizations can lawfully rehabilitate wildlife. California Code of Regulations section 679 specifically addresses wildlife rehabilitation and has incorporated The Minimum Standards for Wildlife Rehabilitation written by the International Wildlife Rehabilitation Council (IWRC) and the National Wildlife Rehabilitators Association (NWRA). To learn more about the permitting process, please follow the link.

Wildlife rehabilitation is a broad and complex field and it is continually evolving and progressing. Continued education is a critical factor when it comes to maintaining a professional knowledge-base at rehabilitation facilities. Because of this, the CDFW requires that all wildlife rehabilitation personnel (professional and volunteer) satisfactorily complete one approved wildlife rehabilitation training session each year. The minimum for these sessions is 2 hours.

Click here for more information on wildlife welfare and rehabilitation and for a complete list of wildlife rehabilitation facilities in California.