Isle Royale Wolf Population Rebounds After Near Disappearance; Reintroduction A Success

The gray wolves (canis lupus) of Isle Royale have seen their numbers rise and fall since their arrival on the Island in 1948. Wolf numbers have been as high as 50 and as low as two. They are currently rebounding after almost going extinct on the island.

In fact, the most recent count shows about 28 wolves on the island. This is up from as few as two a few years ago.

This is important because the island has provided researchers including L. David Mech the perfect opportunity to study wolf -prey interactions. Mech has studied wolves since 1958. He is the author of The Wolves of Isle Royale. He is also closely connected to The International Wolf Center.

Lake Superior and Ontario, Canada
Lake Superior and Ontario, Canada by NASA Johnson is licensed under CC-BY-NC-ND 2.0 A space view of Lake Superior. In addition to holding Isle Royale the lake holds about 10 percent of the world’s freshwater.

The island, the largest in Lake Superior, has been a national park since 1940. The island is about 45 miles long by 9 miles wide. The wolves are believed to have crossed from Canada on an ice bridge during the 1948 winter. The isolation and lack of human contact provided a perfect opportunity to watch wolves interact with prey.

But it came at cost as the isolation of the island “laboratory” led to inbreeding, low birth rates and poor survival. Canine disease eventually reached the island and the population of moose rose and fell, too. Contrary to myth, wolves cannot kill any moose they choose. Healthy moose can stand them off so most of their meals come from old, ill and young moose.

European Wolf, Black Wolf of North America, St.Bernard's Mastiff, Highland Greyhound, and Great Dog of Nepal from A history of the earth and animated nature (1820) by Oliver Goldsmith (1730-1774). Digitally enhanced from our own original edition.
An artist’s view of three dogs and two wolves meeting

According to Newsweek magazine wolves have been captured and relocated to the island to reduce the inbreeding and help stabilize the population. The reintroduction has been a success.

Gray wolves have been persecuted worldwide for centuries but most countries, except Russia, now have protections in place. Reintroduction or support has resulted in growing wolf populations in Italy. Himalayan wolves appear to be increasing their range. In the United States the situation is mixed. Until recently gray wolves could only be found in Michigan, Minnesota and Wisconsin. Since the 1990’s wolf reintroduction and support programs have been initiated. Wolves reintroduced from Yellowstone National Park have spread to Wyoming and Idaho. Wolves from Canada have come to Oregon, Washinton and California, There are plans to reintroduce them to Colorado.

Moose by Alexander Phimister Proctor is licensed under CC-BY 3.0 Moose are large and powerful animals. Their hooves and horns are powerful weapons against wolves. That is why old, sick and juvenile moose are most often eaten by wolves.

But there is pushback. Someone has poisoned wolves in Oregon. Packs have disappeared in California and hunters have waited to kill wolves outside the protection of Yellowstone. The reintroduction in Colorado has met with hostility.

But wolves are fertile and rebound quickly. Newsweek quoted a scientist noting that the Isle Royale events show how quickly wolves can bounce back when not persecuted.

Published by ursusrising

long time writer and editor living in Los Angeles

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