Canada lynx

The scientific name Felis lynx canadensis was proposed by Robert Kerr in 1792 who described a lynx from Canada. In the late 19th century, several lynx zoological specimens were described: • Lynx subsolanus was proposed by Outram Bangs in 1897 for a lynx skin and skull collected near Codroy, Newfoundland. • Lynx canadensis mollipilosus was proposed by Witmer Stone in 1900 who described a skull and a dark brown skin of a male lynx killed near Wainwright, Alaska. The placement of the Canada lynx in the genus Lynx was supported by Gerrit Miller in 1912. Until as late as the early 2000s, scientists were divided over whether Lynx should be considered a subgenus of Felis, or a subfamily itself; some even doubted if the Canada lynx should be considered a species on its own. It was recognized by Wallace Christopher Wozencraft in 2005 as a valid Lynx species along with the bobcat (L. rufus), the Eurasian lynx (L. lynx) and the Iberian lynx (L. pardinus). Wozencraft recognized three subspecies of the Canada lynx: In 2017, the Cat Specialist Group considered the Canada lynx a monotypic species, since it shows little morphological or genetic differences. The lynx population on Newfoundland is thought to have genetically diverged from the mainland Canada lynx around 20,000 to 33,000 years ago following the Last Glacial Period. == Evolution ==

(L. issiodorensis), which is thought to be the ancestor of the four modern Lynx species|alt=Fossils of the Issoire lynx According to a 2006 phylogenetic study, the ancestor of five extant felid lineages—Lynx, Leopardus, Puma, Felis and Prionailurus plus Otocolobus—arrived in North America after crossing the Bering Strait (mya). Lynx diverged from the Puma, Felis and Prionailurus plus Otocolobus lineages around 2.53–4.74mya. The populations of the Eurasian lynx that reached North America 2.6mya are believed to have initially settled in the southern half of the continent, as the northern part was covered by glaciers. The southern populations gradually evolved into the modern bobcat. Later, when the continent was invaded by the Eurasian lynx for a second time within the last 200,000 years, the populations that settled in the northern part of the continent, now devoid of glaciers, evolved into the Canada lynx. In his 1981 paper, Swedish paleontologist Lars Werdelin noted that the Canada lynx does not appear to have changed much since its first appearance. Canada lynx fossils excavated in North America date back to the Sangamonian and the Wisconsin Glacial Episode. }} == Characteristics ==

The Canada lynx is a lean, medium-sized cat characterized by its long, dense fur, triangular ears with black tufts at the tips, and broad, snowshoe-like paws. Like the bobcat, the hindlimbs are longer than the forelimbs, so the back slopes downward to the front. The Canada lynx is sexually dimorphic, with males larger and heavier than females. The lynx is between in total length and stands tall at the shoulder; females range in weight from and males from , though an exceptional male in Pennsylvania weighed . The stubby tail is long and has a completely black tip. Skeletal muscles make up 56.5 % of the Canada lynx's body weight. The long, thick fur, uniformly coloured with little to no markings except on the underside, insulates the lynx in its frosty habitat. The fur is typically yellowish brown, though in Newfoundland it can vary from brown or buff-grey in spring and summer to a greyish shade with a grizzled appearance in winter; the underparts are white and may have a few dark spots. An individual from Alaska was reported to have bluish-grey fur. The fur is generally shorter in summer than in winter. The backs of the ears are brown with a silvery-grey spot at the centre. Both species walk with the back foot typically following the front foot and often do not follow a straight line. The lynx's stride is , while the bobcat's varies between . Canada lynx tracks are generally larger than those of the bobcat; thicker fur may make the toe pads appear less prominent in the snow. In dirt the tracks of the lynx are long and wide, whereas in snow they are bigger ( long and wide). The warm coat, wide paws and long legs serve as adaptations for the lynx to navigate and hunt efficiently in snow. The dental formula is . The deciduous dentition is , as the young do not have molars. The Canada lynx can be told apart from the bobcat by its longer ear tufts, broader paws, shorter tail with a fully black tip, longer legs and the fewer markings and greyer shade of the coat. The bobcat is generally smaller than the Canada lynx, but in areas where they are sympatric the bobcat tends to be larger and may still be confused with the Canada lynx. == Distribution and habitat ==

The Canada lynx occurs predominantly in the dense boreal forest of Canada, and its range strongly coincides with that of the snowshoe hare. In the past, the lynx occurred in the northern United States in 24 states, possibly southward to the Rocky Mountains in New Mexico and northward to the tree line in the Arctic through coniferous forests in Alaska and Canada. The lynx continues to occur in its former range in most of Alaska and Canada. In the United States, the Canada lynx occurs in the Blue Mountains and the Cascade Range in the Pacific Northwest, the Rocky Mountains, the northern Great Lakes region (in Minnesota and Michigan's Upper Peninsula) and northern New England (in New Hampshire, Maine and Vermont). The lynx was successfully reintroduced in Colorado starting in 1999, after being extirpated from the state in the 1970s. Canada lynxes generally avoid open areas despite good prey availability; they face difficulty surviving in heavily logged areas and on agricultural land, though they can thrive well in deforested areas that have been left to regenerate at least fifteen years. Canada lynxes have been recorded up to an elevation of . In February 2022, a picture of a large male Canada lynx was taken by a hunter in the southern Gros Ventre Range of Wyoming after his hounds treed the cat, making it the first confirmed sighting in the state since 2012. == Ecology and behaviour ==

The Canada lynx tends to be nocturnal like its primary prey, the snowshoe hare. Nevertheless, activity may be observed during daytime. These lynxes are good swimmers; one account records a Canada lynx swimming across the Yukon River. Canada lynxes are efficient climbers, and will dodge predators by climbing high up in trees, but they hunt only on the ground. Individuals of the same sex particularly tend to avoid each other, forming "intrasexual" territories—a social structure similar to that of bears, bobcats, cougars and mustelids. Intraspecific aggression and consequent cannibalism are rare, but may be more common when food is scarce. Home ranges Canada lynxes establish home ranges that vary widely in size, depending upon the method of measurement. The two common methods are examining the tracks of the lynx in snow (snow-tracking) and radio telemetry; snow-tracking generally gives smaller sizes for home ranges. Studies based on snow-tracking have estimated home range sizes of , while those based on radio telemetry have given the area between . However, a few other studies have reported different responses from Canada lynxes at times of prey scarcity; some lynxes do not show any changes in their ranges, while others may resort to hunting in small areas, occupying small home ranges. Males tend to occupy larger ranges than do females; for instance, data from a 1980 radio telemetric analysis in Minnesota showed that males' home ranges spread over , while those of females covered . In a study in the southern Northwest Territories, ranges of individuals of opposite sexes were found to overlap extensively, while the ranges of individuals of the same sex hardly coincided. The study suggested that individuals do not show any significant tendency to avoid or mingle with one another, and thus only passively defend their ranges. However, Canada lynxes are known to disperse over large distances, often thousands of kilometres, which might increase genetic variability in widely separated populations. They typically move within areas where prey availability and the features of the snow (such as the hardness and the extent to which their paws sink into the snow) are more or less similar; individuals may disperse over smaller areas in areas of soft snow. Diet and hunting is the primary prey of the Canada lynx.|alt=A snowshoe hare sitting on snow The Canada lynx preys primarily on the snowshoe hare. These hares comprise 35–97% of their diet; the proportion varies by the season and the abundance of hares. They have also been reported feeding occasionally on succulents, sedges and grasses. A study of those two animals in southwest Yukon showed that when the hare population increased, both killed more than necessary for subsistence; lynxes need to kill 0.4 to 0.5 hare per day to meet their energy requirements but were observed to kill 1.2 hares per day during this period. Coyotes, with a success rate of 36.9%, emerged as more successful hunters than lynxes that succeeded in 28.7% of their hunts; however, this may have resulted from the greater number of adult coyotes in the studied population. Lynxes rarely cached their kills, unlike coyotes, and this may have led to incomplete consumption of some kills. When snowshoe hare numbers declined, both predators hunted for the same time period as they did when hares were abundant, but lynxes killed more hares than they had earlier. Moreover, lynxes supplemented their diet with American red squirrels. Relationship with the snowshoe hare (Lepus americanus) (yellow background) and Canada lynx (black line, foreground) furs sold to the Hudson's Bay Company from 1845 to 1935|alt=A line graph of the number of Canada lynx furs sold to the Hudson's Bay Company on the vertical axis against the numbers of snowshoe hare on the horizontal axis for the period 1845 to 1935 A specialist predator, the Canada lynx depends heavily on snowshoe hares for food. In northern Canada, the abundance of lynxes can be estimated from records maintained by the Hudson's Bay Company and the Canadian government since the 1730s. Lynx populations have been found to vary periodically three- to seventeen-fold. A study involving statistical modelling of the interspecific relations of the snowshoe hare, the plant species it feeds on and its predators (including the Canada lynx) suggested that while the demographics of the lynx depend primarily on the hare, the hare's dynamics depend on both its diet and its predators, of which the Canada lynx is just one. Environmental factors such as forest fires, precipitation and snowfall might also significantly affect this prey-predator cycle. Reproduction The mating season is roughly a month long, from March to early April. Urine marking and mating calls are part of display behaviour and increase the interaction between individuals of opposite sexes. Females can be induced ovulators when the availability of mates is low, or spontaneous ovulators when several mates are available. Females have only a single estrus cycle; estrus lasts three to five days in captivity. Before birth, the female prepares a maternal den, usually in very thick brush, and typically inside thickets of shrubs, trees or woody debris. After a gestation of two to three months, a litter of one to eight kittens is born. Kittens weigh from at birth and initially have greyish buff fur with black markings. They are blind the first fourteen days and weaned at twelve weeks. Most births occur from May to July. Kittens leave the den after about five weeks and begin hunting at between seven and nine months of age. They leave the mother at around ten months, as the next breeding season begins, but they do not reach the full adult size until around two years of age. Female offspring typically settle in home ranges close to their mothers and remain in contact with them for life, while male offspring move far from their mother's range. Females reach sexual maturity at ten months but often delay breeding another year; males mature at age two or three. Canada lynxes have been reported to live sixteen years in the wild, though most do not survive ten; in captivity they may make it to twenty-seven. Diseases and mortality The Canada lynx is known to host several parasites including Cylicospirura felineus, Taenia species, Toxocara cati, Toxascaris leonina and Troglostrongylus wilsoni. Canada lynxes could have played a role in the transmission of the zoonotic parasite Toxoplasma gondii to the Inuit in North America. A study in 2019 identified a gammaherpesvirus species in the Canada lynx for the first time. The study discovered a novel percavirus, named LcaGHV1, in spleen samples of Canada lynxes from Maine and Newfoundland. A study identified plague as a major cause of mortality in reintroduced populations in Colorado. Fishers are known to hunt Canada lynxes occasionally in the northeastern United States; a study in northern Maine identified predation by fishers as the leading cause of Canada lynx mortality over twelve years, though it did not appear to affect population growth in the lynxes. == Interactions with humans ==

Trade Canada lynxes are trapped in specific seasons in most of Alaska and Canada; hunting seasons and quotas are set based on population data. Alberta typically leads in the production of pelts, accounting for nearly a third of Canada's total. Following a cyclic fall in populations during the mid to late 1980s, there was a sharp decline in the prices and harvest of Canada lynx furs—the average number of pelts exported from Canada and the United States fell from 35,669 in 1980–1984 to 7,360 between 1986 and 1989. Subsequently, the numbers have increased to 15,387 during 2000–2006. Average illegal trade in fur and live animals appears to be negligible on the national scale. Even without regulation, the lynx-hare cycles and the distribution of the lynx have remained unaffected over the last century. Threats and conservation In eastern Canada the lynx is threatened by competition with the eastern coyote, whose numbers in the region have risen in the last few decades. Habitat loss is the main threat in the contiguous United States, while trapping is a relatively insignificant cause of mortality. The Canada lynx is abundant over its broad range and has not been significantly threatened by legal trade for centuries. Therefore, the International Union for Conservation of Nature and Natural Resources (IUCN) classifies the Canada lynx as Least Concern. In 2005, the USFWS demarcated six major areas for revival where lynx reproduction had been reported in the past two decades: northern Maine and New Hampshire, northeastern Minnesota, northwestern Montana and northeastern Idaho, the Kettle River Range and the "Wedge area" between the Kettle and Columbia rivers of Washington, the northern Cascade Range of Washington, and the Greater Yellowstone area of Wyoming, Montana and Idaho. A 2012 study showed numbers had improved in the northeastern United States; however, a 2008 study showed lynx populations were not doing well in Washington because of habitat fragmentation. A 2017 study reported increasing numbers in many areas in the United States. In January 2018, the USFWS declared that the Canada lynx no longer needed special protections in the United States following measures to preserve their populations, and their "Threatened" status may be revoked in the future. Various techniques have been employed to study Canada lynx populations; the data collected can provide useful information on the ecology and distribution of the species and pave the way for effective conservation measures. In scent stations, the lynx is typically lured into camera-monitored areas by skunk scent (sometimes catnip) and a "flasher" such as a bird wing on a string. This technique, though systematic, might be too expensive to carry out in large areas. Other methods include radio telemetry and snow tracking. Snow tracking might be a challenge in areas lacking roads, and sometimes bobcat tracks can be mistaken for those of the Canada lynx. Hair-snaring involves collecting hairs shed by the lynx, especially when they rub against objects (such as the snow); a study showed a mixture of beaver castoreum and catnip oil can strongly induce rubbing behaviour in lynxes. This method is generally inexpensive, and chances of misidentification are low as physical evidence like hairs can be genetically analysed. Nineteen of the reintroduced lynx were killed in traffic accidents, eight were mistakenly shot by bobcat hunters, and the remaining died from unknown causes or predation. == See also ==