Fishers, often colloquially called “fisher cats,” are fascinating but misunderstood creatures. They belong to the weasel family (Mustelidae) and are known for their agility, hunting prowess, and important ecological role. Fishers are neither anglers nor cats, but are powerful, agile hunters with a crucial role in their ecosystems. Fisher sightings in Ontario are on the rise, likely due to a combination of habitat recovery, climate change, and range expansion. Here are some common misconceptions about fishers:
1) They eat fish
Contrary to what their name may suggest, fish is not a regular part of a fisher’s diet. Fishers are opportunistic carnivores that prey on rodents, birds, amphibians, small reptiles, and insects—they’re also one of the few mammals known to actively hunt porcupines. They are also known to kill animals larger than themselves, such as lynx.
2) They target pet cats
Although vicious in their hunting capabilities, instances of fishers hunting pet cats are rare and often exaggerated. According to studies analyzing the stomach contents of fishers, cat hair is found only in one case out of a thousand. Fishers are likely blamed for the disappearance of pets because of their elusive nature and formidable hunting capabilities.
3) They’ll approach humans
Fishers are shy and solitary animals. They avoid human contact whenever possible. If you see a fisher, do not fret—they want even less to do with you than you do with them!
4) The don’t contribute ecologically
Fishers play an important role in cottage country as mesopredators. This means that they help regulate the populations of smaller prey species, and help maintain forest ecosystems. Their presence helps prevent the overpopulation of herbivores such squirrels and hares, which subsequently supports healthy vegetation growth.
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