By Shauna Potocky
January 5, 2015 will be a pivotal day in the future of the Pacific fisher along the West Coast of the United States. An extraordinary predator of the mixed conifer forest, the Pacific fisher was once abundant throughout the forested areas of the United States and Canada. Fisher populations rapidly declined due to hunting and timber extraction in the mid 1800 through the early 1900s. Today, the fisher is affected by development, timber extraction, fires, toxins and forest fragmentation—but the fisher’s story does not end here. In fact, there is a chance to write an entirely new chapter for the West Coast populations of fisher, focused on its future.
Previous attempts to protect the Pacific fisher under the Endangered Species Act have not resulted in it being listed, but soon that track record may change. Increased pressures on the West Coast population of fishers, along with consistent monitoring of the population by a wide range of professionals and stakeholders, have culminated in what may be an important review and opportunity to list the fisher as threatened via the Endangered Species Act. This may afford a new level of protection and suite of management strategies to help preserve the existing population and potentially assist in its eventual recovery.
The natural history of the fisher has made it uniquely susceptible to various human pressures. A member of the weasel family, also known as mustelids, the fisher is essentially the middle cousin between the smaller American martin and the larger wolverine. Yet, what might help one understand the appeal of the fisher, is that it is also related to the sea otter—and shares many characteristics of its remarkable fur. This fur is what made the fisher a valuable commodity during the settlement of the United States and the fur trapping and trade of the time. That, along with its dependence on forested areas as habitat, put it in direct competition with a young country looking to extract lumber and build its future infrastructure.
The result was that the fisher declined in many areas of the United States and went extinct along parts of its range on the East Coast. Reintroductions have helped to bring the fisher back to its historic range. Yet, today, there is a population of fishers still eking out a living on the West Coast—primarily in Washington, Oregon and California. Perhaps the most remarkable of these populations is the geographically isolated population of fisher in the Southern Sierra Nevada of California. Here, a small population of just several hundred individuals is hanging on—though, they are facing big odds. That said, there are many people working to explore the issues, find solutions and potentially turn the odds in the fisher’s favor.
Research groups are working to better understand the needs and critical habitat of the fisher, this work enables them to collaborate with and inform communities, businesses, agencies and other research groups on adaptive management strategies that can best support the fisher in its remaining habitat. Essentially, this work can help in effectively preserving or restoring habitat and potentially bridge or solve the fragmentation gap—thus reuniting the fisher within its historic range.
The Pacific fisher preys on small mammals such as mice, squirrels and is famously known for predating porcupines. It is generally found in close proximity to a water source and prefers a closed canopy forest. Perhaps most importantly, is its dependence on medium to large trees as an essential part of its habitat. Specifically, the female fisher utilizes cavities in trees as dens for resting, giving birth and raising her young, known as kits. Smaller trees generally do not provide den space—thus, the fisher is associated with forests that have larger diameter trees.
The fisher is well adapted for climbing trees; it has large paws that feature impressive claws, which aid in climbing. The fisher is also a skilled predator—it may look remarkably cute, but don’t be fooled, it is an effective hunter. Unfortunately, as an ironic twist of predator fate, the fisher has become the center piece of an emerging issue in forests and public lands, especially in California.
Illegal marijuana farms are permeating public lands throughout areas of the Southern Sierra Nevada. In these areas national forests, national parks and other remote forested landscapes have fallen prey to marijuana growers who have no regard for public lands, the forest, water resources and the wildlife that reside there.
Entire areas of forest may be cut or thinned in order to cultivate marijuana. Water is plumbed from streams and there is no remorse for killing wildlife—either for illegal hunting or to protect the marijuana crop itself. This second motivation has resulted in heavy poisons being used in forest landscapes in order to kill mice, squirrels and other animals that may jeopardize the crop. These poisons, known as rodenticides, bioaccumulate in the food web, and the fisher has emerged as a major victim.
In a population that is already facing great pressures from land use, resource extraction, vehicle collisions, an increased threat of fire, as well as geographic isolation—there is now an option to do something for the Pacific fisher.
January 5, 2015 is a fast approaching deadline. The United States Fish and Wildlife Service is providing the public with an opportunity to weigh in on whether the Pacific fisher should be protected via the Endangered Species Act. Whatever your opinion, don’t sit silent—we are being given the opportunity to speak up and the future of the fisher is on us. Its fate will be determined on our watch.
Featured image: USFWS Pacific South West Region courtesy of Creative Commons.