Featured Research

from universities, journals, and other organizations

Wolves In Isle Royale National Park Bounce Back

Date:
March 12, 1999
Source:
Michigan Technological University
Summary:
The wolves of Isle Royale National Park have surprised scientists again by staging a dramatic comeback just when wildlife managers were worried that the island park's most storied species might be headed for trouble.

HOUGHTON, MI--The wolves of Isle Royale National Park have surprised scientists again by staging a dramatic comeback just when wildlife managers were worried that the island park's most storied species might be headed for trouble.

Related Articles


Several times during the past two decades biologists have felt that canine parvovirus or a perceived genetic weakness resulting from inbreeding was placing the wolves' survival in grave jeopardy. And when last winter's survey turned up only 14 wolves in the park, those concerns increased.

But what a difference a year makes!

Park Superintendent Douglas Barnard announced today that this winter's survey showed the island's wolves had boosted their numbers to 25. "That's the most wolves we've had in the park since 1981 and the biggest annual increase ever," he said. Barnard said the increase was due primarily to high reproductive success by two of the island's three wolf packs.

"Two of the packs produced six pups apiece," he said. "One pack comprised of only a male and female didn't have any pups survive, and there are three single wolves wandering around out there without any pack affiliation."

Michigan Tech's Dr. Rolf Peterson, who conducts the annual winter wolf-moose census for the National Park Service, points to two main causes for the wolves' reproductive success this year.

"The park's moose have been generally in poor condition due to a heavy winter tick infestation caused by the mild winter and early spring of a year ago," he says. "The unusual heat of the summer also made it difficult for them to put on the fat required to survive through the winter." Peterson says the resulting diminished vigor made moose easier prey for wolves.

"Secondly, there are lots of moose calves now, and an increasing number of adults who are reaching old age. Both make easy prey for wolves," he explains.

Peterson says the park's East and Middle packs each produced six pups during the past year, so that these packs now number 10 wolves apiece. "We believe the West pack produced three offspring, but none of them survived," he says. "We don't know why for sure, but it may well have to do with the scarcity of moose at that end of the island." He says the park's moose population numbers 750 this year, as compared to 700 a year ago, with most of the animals concentrated in the east and middle portions of the island.

Peterson is encouraged by the fact that dead wolves found by the survey crew during the past few years have been disease-free and showed no direct signs of any genetic problem that biologists thought might have caused poor reproduction in past years. In the past year only one wolf has died on Isle Royale, and biologists determined that it had been killed in a territorial dispute by other wolves.

National Park officials are hoping for continued positive growth in the wolf population that would keep the total number of wolves on Isle Royale in the high 20s during the next several years.

Wolf research on Isle Royale is funded by the National Park Service, National Science Foundation, and Earthwatch.


Story Source:

The above story is based on materials provided by Michigan Technological University. Note: Materials may be edited for content and length.


Cite This Page:

Michigan Technological University. "Wolves In Isle Royale National Park Bounce Back." ScienceDaily. ScienceDaily, 12 March 1999. <www.sciencedaily.com/releases/1999/03/990312061821.htm>.
Michigan Technological University. (1999, March 12). Wolves In Isle Royale National Park Bounce Back. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/1999/03/990312061821.htm
Michigan Technological University. "Wolves In Isle Royale National Park Bounce Back." ScienceDaily. www.sciencedaily.com/releases/1999/03/990312061821.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Kids Die While Under Protective Services

Kids Die While Under Protective Services

AP (Dec. 18, 2014) As part of a six-month investigation of child maltreatment deaths, the AP found that hundreds of deaths from horrific abuse and neglect could have been prevented. AP's Haven Daley reports. (Dec. 18) Video provided by AP
Powered by NewsLook.com
Dads-To-Be Also Experience Hormone Changes During Pregnancy

Dads-To-Be Also Experience Hormone Changes During Pregnancy

Newsy (Dec. 18, 2014) A study from University of Michigan researchers found that expectant fathers see a decrease in testosterone as the baby's birth draws near. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins