We pulled out of the parking lot at dawn after one of the first nights of frost, raw chicken drumsticks and a can of synthetic stink bouncing around in a cooler in the bed of the truck. From town we drove west into the hills between Upper Klamath Lake and the Rogue Valley to check our first trap.
The BLM was in the midst of a fisher study, and I was fortunate enough to get the opportunity to tag along with one of the lead biologists for a day. Fisher are small carnivorous mammals in the weasel family and the marten genus. They are primarily solitary animals, with the females occupying relatively large home ranges and the males moving between female ranges to mate. (Fun fact about fisher reproduction, while fisher mate in the early spring, they have delayed implantation so gestation doesn’t begin until the following fall!) While fisher were once relatively common in the western United States, heavy trapping for their pelts led to their extirpation in a large part of their historic range. A population remained in south western Oregon and another population was established through reintroduction west of Crater Lake, Oregon. It is believed that these two populations may have merged to create the population that now occupies the area west of Upper Klamath Lake. The BLM is currently conducting a multi-year study to learn more about this population of fisher.
On the morning I checked traps with the BLM biologist, approximately 20 traps had been set and 5 separate groups were out checking traps. The traps consist of a have-a-heart trap connected to a wooden box. Traps are set against logs that are generally located on ridges or in narrow swaths of forest between open areas. To avoid predation, fisher prefer to travel in higher areas with adequate cover. Traps are camouflaged with bark, monitored with a motion sensor camera strapped to a nearby tree. A very strongly scented lure that smells like sweet skunk is spread around the area to attract animals, and a piece of raw chicken is hung inside the trap. Once an animal enters the trap to grab the chicken, the door springs shut behind it. When fisher find themselves trapped, they generally take the chicken, go hide in the wooden box behind the trap, and enjoy their meal. Traps are checked each morning to see whether a fisher (or other critter) has been caught and to refresh the lure and chicken if needed.
Arriving at our first spot, we hopped out of the truck, grabbed our supplies, and followed the candy stripe flagging tape and increasingly strong smell of what the biologist I was with affectionately referred to as ‘pepe’ to the trap. While we did find a trap with the door closed, it was clear this was not the doing of a hungry fisher, but rather a curious bear. We set the trap back in place, covered it with bark, and propped the door open. I tried to hide my disappointment when three traps later all we had found were open doors or bear tossed traps. Just as I was resigning myself to a fisher-free day, we received a text from another biologist who had caught what she believed to be a juvenile female fisher in a nearby trap.
After all traps had been checked, we convened at the location with the fisher to process the animal. It took about 10 minutes to coax the fisher out of the wooden box, through a canvas tube that resembled a very large frosting bag, and into a fisher-sized wire cage. My job was to wait until the fisher scurried out and found itself stuck face first in the wire cage and then jam wooden dowels in behind it to ensure it didn’t retreat into the bag. Once in place, one of the biologist gave the fisher a general anesthetic.
Various measurements and samples were taken including weight, length, girth, hair samples, blood samples, fir samples, tick samples, a tissue sample, ocular, nasal, and rectal swabs, and a tooth. The animal was monitored throughout the process to ensure an appropriate body temperature was maintained. While the BLM often puts radio collars on fisher to track their movement, this fisher did not receive a collar because it was likely not fully grown and a collar could lead to problems if the animal continued growing. A passive integrated transponder (PIT) tag was injected so the individual could be identified if recaptured. Poking and prodding complete, the fisher was returned to the wooden box to recover for a few hours before being released in the same area where it was captured. After two unsuccessful attempts to climb a nearby tree, which involved the fisher losing grip, flying through the air, and miraculously landing on all fours, the fisher finally wobbled its way up the trunk and clung to a branch, watching us until we drove away.
Although the day probably left the fisher feeling a little sore and woozy, the capture allowed the BLM to add to its data set and knowledge about fisher in the area, and gave me the incredible opportunity to be involved in capturing, processing, and releasing an animal that few people are lucky enough to ever see.