Canada Lynx, Lynx canadensis
Canada lynx have a unique appearance among felids, especially Neartic ones, including a flared facial ruff, black ear tufts and long hind legs, which lend a slightly stooped posture. The tail is short and black-tipped. Pelage is reddish-brown to gray; the hairs are tipped with white that give it a frosted appearance. The Canada lynx’s large, spreading feet act like snowshoes and support twice the weight on snow as bobcat paws. Adult males weighing between 22 to 40 pounds (10 to 18 kg) are generally larger than females, which weigh between 18 to 34 pounds (8 to 16 kg).
Lynx show remarkable similarity of appearance between subspecies. The Canada lynx, however, is only half the size of the Eurasian lynx and exhibits marked adaptive differences in prey selection, supporting mitochondrial analysis that tends to support separate species status. While the Canada lynx is probably a descendent of the Eurasian lynx ancestor which migrated into North America during one of the last two major glacial periods, the much larger Eurasian lynx preys mainly on ungulates (roe deer) while the Canada lynx relies almost exclusively on snowshoe hares and is uniquely adapted, both behaviorally and physiologically, to exploit this cyclic prey base.
Lynx are inexorably linked to the snowshoe hare as its primary food source and as such, are commonly found at higher densities in riparian areas and areas of new-growth coniferous forest such as after forest fires. Such areas attract snowshoe hares and thus lynx may concentrate in these areas. Canada lynx have been shown to use mature forest stands and will inhabit farming country, but only if it is interrupted by sufficient areas of woodland that contains hare populations. As more generalist feeders, bobcats are expanding their range northward in some areas, although there appears to be a very distinct partitioning of niches between these two felids due to snow depth.
Lynx are distributed throughout the broad boreal, sub-boreal and western montane forests of North America and range into the American Rocky Mountains and Cascades of the Pacific Northwest, northern Minnesota and northern New England. Most of the historical range is intact, although it has shrunk in the south due primarily to human settlement, fire suppression and forest maturation, harvest and forest clearance. Records have documented lynx in the northern tundra, Iowa, South Dakota, Nebraska and Pennsylvania.
Canada lynx feed almost exclusively on snowshoe hares, a cyclic prey species that has a profound impact on lynx populations. Recruitment of lynx populations is near zero and adult mortality is much higher at the bottom of hare cycles.
Home ranges for lynxes range from 1.5 to 9.6 miles squared (4 to 25 km2) for females to 1.5 to 27 miles squared (4 to 70 km2) for males. Male ranges usually encompass those of females but some same-sex overlap has been found. It is thought that the same-sex overlap reflects the high degree of tolerance of independent offspring by resident lynx, another unusual adaptation to a predictably cyclic prey base.
Because they are linked to the population cycles of snowshoe hares, Canada lynx may be induced ovulators when prey density is low and spontaneous ovulators when prey density is high, thus improving the prospects for breeding and raising young. After a gestation of 60 to 65 days, a litter of three to five cubs is produced. When prey is scarce, production and survival of young is very low. Juveniles mature at 10 months when prey is abundant, but at two years when prey is scarce. Survival rates vary dramatically with the hare cycle, but upwards of 90 percent survival before and during a decline in hares, to lows of 9 to 40 percent of the adult population in the first and second years respectively following population crashes of the hare. In captivity, lynx can reach at least 15 years of age.
Lynx are primarily terrestrial and nocturnal as are the snowshoe hares upon which they prey. When hunting, lynx may travel back and forth between patches of cover, actively seeking out hares. Another method of hunting is to sit and wait for hares to pass by and then launch an ambush attack. They may eat prey as it’s killed or cache it for later, covering it with snow or leaves.
Threats to Survival:
In general, the future of the lynx looks more promising than for many other felids. Problems persist, however, as harvests during the cyclic low period have progressively fallen since the mid-1970’s and have not recovered. At the low point of hare cycles, lynx become more vulnerable to trapping as they disperse in search of food, traveling greater distances and thus being exposed to greater trapping opportunities. The suspension of trapping quotas during low hare years has been recommended by some biologists, as has a quota system for lynx as their numbers increase. Except in the Lower 48 states, habitat alteration is thought to have had limited impact on lynx populations. In the southern portions of their range, optimal hare habitat is more patchily distributed and logging practices may further exacerbate the distribution of lynx.
Canada lynx were listed in 2008 as Least Concern by the IUCN. They are however, protected in international trade on CITES Appendix II. In April 2000, Canada lynx were listed as Threatened on the U.S. Endangered Species Act. This threatened status covers wild populations of the Lower 48 states and all animals held in captivity within the United States. In Canada and Alaska, trapping is regulated through closed seasons, quotas, limited entry and long-term trapping concessions; these regulations cover both the nominate form, L. c. canadensis, which is by far the most widely distributed subspecies, as well as the subspecies indigenous to the island of Newfoundland, L. c. subsolanus.
The North American captive population is managed by a Regional Studbook and is a Yellow SSP with a target population of 80 animals. As part of the Regional Collection Plan, the TAG recommends replacing all taxa of Eurasian lynx as well as bobcats with Canada lynx where possible in AZA institutions.
Canada Lynx SSP Coordinator & Studbook Keeper
Amanda Ista, Milwaukee County Zoo
In 1999, Colorado began a Canada lynx restoration program. By 2005, more than 200 lynx had been released with a number of kittens born. The reintroduction program has been deemed a success.