A now-rare forest carnivore faces numerous hurdles to continue living in its usual habitat, wildfire chiefly among them.
Canadian Lynx numbers have declined throughout most of their range in the United States, according to the Endangered Species Coalition. Causes for their decline include habitat loss, urbanization, and genetic isolation from populations in Canada due to the fragmentation of their environment.
Now, the remaining morsels of the species’ habitat is facing additional threats, straining the animals even further. A recent study used GPS data and scientific modeling to identify the remaining lynx habitat in the forests of western Colorado, southern Wyoming, and northern New Mexico, and considered over 40 habitat or environmental characteristics to identify the area’s biggest risks.
The maps found that lynx habitat in these areas is now sparse, patchy, and poorly connected, existing only in narrow bands due to Colorado’s complex mountainous terrain. Researchers also said that around one-third of the likely habitat overlapped with multiple disturbances between the study’s timeframe of 1990 and 2022, including forest insect outbreaks (31%), wildfires (5%), and forest management activities like tree harvest and prescribed burning (3%).
“Although fire disturbance from 1990-2022 overlapped only 5% of likely lynx habitat in this area, we believe that frequent, high-severity fire is the main risk to lynx in high-elevation forests moving forward,” Dr. John Squires, the study’s principal investigator and a Rocky Mountain Research Station research wildlife biologist, told Phys.org.
Researchers predicted wildfire would be a primary disturbance factor for the animal’s critical habitat. The 94,545-hectare Cameron Peak Fire, the 78,433-hectare East Troublesome Fire, and the 56,254-hectare Pine Gulch Fire, all burned lynx habitat during the 2020 fire season.
Despite the low overlap percentage the study eventually found, the scientists still considered wildfire to be the highest threat to lynx habitat, in part due to projected increasing trends in wildfire frequency and severity. Some fire threats have already demonstrated the fire vulnerability of lynx habitat.
“The West Fork Fire Complex…burned at high severity across 442 km2 of the San Juan Mountains in 2013, impacting one of the most important patches of lynx habitat in the Southern Rockies,” the study said. “In general, lynx avoid fire-impacted landscapes for at least ~ 25 yrs, likely because stand-replacing fires of high severity that are common in subalpine systems reset much of the impacted area to a stand initiation stage.”
For example, fires in Washington’s North Cascades Ecosystem in 2o13 and 2020 burned an estimated 32% of lynx habitat and reduced the species’ carrying capacity between 66% and 73%, the researchers said. Ultimately, how much fires affect lynx landscape depends on the extent, frequency, and severity of the fires.
“Therefore, despite low current overlap, a central conservation issue for lynx and forest management in the Southern Rockies is how to “defend” Likely, in situ habitat from frequent fire disturbance with climate change,” the researchers said.
