ORDER

Carnivora (carnivores)

FAMILY

Mustelidae (badgers, otters, skunks, weasels and relatives)

HABITAT AND RANGE

The fisher can be found in central and southern Canada, northern California, in the Rocky Mountains and in New York and New England. They prefer to live in thick coniferous or mixed coniferous and hardwood forests with lots of tree cover and hollow trees to use as dens.

IDENTIFICATION

The fisher has a long body and dark brown to light brown fur. It has long claws on both its hind and front paws. Its front and hind legs are black and it has a long, thick, black tail. It has a short muzzle and round ears on the sides of its head. They can grow up to 1.2 meters long and weigh between 3.5 and 5 kg for males and 2 to 2.5 kg for females.

DIET

Fishers eat rodents, birds, insects, carrion and sometimes fruits. Despite their name, they rarely catch and eat fish. They will often hunt porcupines by attacking the face repeatedly until the porcupine becomes exhausted. They then flip their prey over and attack the soft, unprotected belly. Porcupines are not easy prey however and will sometimes badly injure or even kill fishers with their quills.

REPRODUCTION AND LIFESPAN

The breeding season is late winter and early spring. After fertilization, the embryos sit in suspended development for 10 to 11 months, and resume developing late in the winter following mating. Overall, gestation lasts almost a full year, 11 to 12 months. The average number of young in a litter is 1 to 5. Females can and usually do mate almost immediately after birth. The young nurse for 5-8 weeks but do not leave their mothers until they are 6 months old. Because of their mating cycle, females will be either pregnant or lactating throughout their lives. Delayed implantation is perhaps easier than finding a mate in the winter when gestation begins. Sexual maturity in females is reached after 1 year and after 2 years for males. Lifespan is about 10 years.

NOTES

Fishers and American martens are the only American carnivores that are very agile tree climbers and yet posses the ability to elongate their torsos to invade burrows of other animals. Fishers claws are retractable allowing them to be kept very sharp to aid in tree climbing. Fishers are also very good swimmers.