Expert: Jonathan Wright - 5/25/2004

Question
Hello! I was wondering about a couple things about the canadian lynx like what genetic variations were found within this species like anything physical, or internal; and, I was also wondering what adaptions this species has evolved to survive it's enviroment.

Answer
Dear Student

Thanks for your question.

There is some confusion about whether the Canadian lynx is a distinct species, so I checked with a book published in 2004. ‘Mammals of the World' by Andrew Duff and Ann Lawson, published by A & C Black Publishers Ltd considers that the Canadian lynx (Felis canadensis) is a species distinct from the Eurasian lynx (Felis lynx).  It is only half the size of the Eurasian lynx, has a shorter tail and longer hind legs and shows differences in prey selection. The Eurasian lynx preys mainly on roe deer, while the Canadian lynx is adapted to feed on the snowshoe hare. Mitochondrial analysis tends to support separate species status, but the Canadian lynx is probably a descendant of the Eurasian lynx which migrated into North America during one of the last two major glacial periods.
There are two subspecies – the mainland lynx (F.c. canadensis) and the larger Newfoundland lynx (F.c. subsolanus).  The mainland lynx is found in boreal forests of Alaska and Canada and locally in west and northeast USA. The Newfoundland lynx is indigenous to the island of Newfoundland. Apart from size, I couldn't find any genetic variations within the species. Please note that there was a third subspecies - the Arctic lynx (F.c. mollipilosus), but this form, with a browner pelage and a very dense, soft, woolly pelage is no longer considered distinct.

The Canadian lynx has adapted to its snowy habitat by growing a thick coat of fur and by having large, spreading feet. The soles of the feet have thick cushions of dense, coarse hair in winter. These keep the feet warm and enable the feet to act like snowshoes, enabling the lynx to walk easily and silently on the surface of deep snow, in which some prey may flounder. The paws support twice the weight on snow as do bobcat paws. The big feet also enhance swimming. The long ear tufts serve as sensitive antennae to enhance hearing.

The lynx is adapted behaviourally and physiologically to exploit the periodic ‘boom and bust' population cycles of the snowshoe hare. Hare numbers peak every 10 years. The lynx is often found at higher densities in riparian areas and areas of new-growth coniferous forest, such as after forest fires, as such areas attract snowshoe hares. The lynx may be an induced ovulator when prey density is low and a spontaneous ovulator when prey density is high. This improves the prospects for breeding and raising young. Survival rates vary dramatically with the prey cycle, upwards of 90% survival before and during a decline in hares to lows of 9-40% of the adult population in the first and second years respectively after population crashes of the hare. Juveniles mature at 10 months when prey is abundant and at two years when prey is scarce. When hares are abundant, more lynx survive to reproduce and their numbers increase.

As the hares start to decline, so do lynx numbers after a two year lag and many lynx die from starvation. Fewer lynx reproduce and litter size decreases, with very low survival of the young. Recruitment of lynx populations is near zero and adult mortality is much higher near the bottom of hare cycles. e decreases. While lynx continue to breed during crash years, females have difficulty supporting themselves and their young on a reduced food supply and few kits survive. Adults may migrate to other areas to find food. When snowshoe hares are scarce, lynxes may feed on small to medium-sized mammals (voles, squirrels etc) and birds (grouse etc), as well as the remains of larger animals, such as deer.

Please note that the Canadian lynx is often considered to be a subspecies of the northern lynx (Fleis/Lynx lynx), but I have considered it as a distinct species for the reasons listed above.

I hope this has helped you with the question. The main adaptations are the ears, feet and following the cycle of the snowshoe hare. I have decided not to include adaptations shared with other species of cat, such as retractile claws etc.

All the best

Jonathan