Why Deer Die

Wisconsin deer trap“Hunter harvest continues to be the greatest cause of death of both adult and yearling bucks, while predation was the leading cause of fawn mortality, with most predations occurring within the first four to six weeks following birth,” said Jared Duquette, research scientist with the Wisconsin Department of Natural Resources and lead researcher for a five-year study of causes of adult deer mortality and a three-year study of fawn mortality in an item in department’s weekly news bulletin.

According to the weekly news summary:

Capture of adults will continue through the 2012-13 and 2013-14 winters. Fawns were live-captured in May and June in 2011 and 2012 and will be captured again in 2013. A number of captured adults and fawns are fitted with radio collars. All are fitted with ear tags. Additional metrics are collected including body weight and size, blood samples, sex, presence of external parasites and age. Does are also examined for pregnancy. Deer are followed by radio signal until death, at which time researchers study the mortality to determine cause.

More details on the two studies are available in the department’s news report. Wisconsin is also conducting some other interesting deer studies. You can see the list here. I’d be interested to know the results of “An evaluation of the usefulness of deer-vehicle collision data as indices to deer population abundance.”

Read the weekly news item detailing the two deer studies here.

Photo: Closed box trap with deer feeding around it, courtesy of the Wisconsin Department of Natural Resources.

March Roundup of New Research

Spring is here and a bunch of wildlife surveys are underway around the country.

In Delaware:
-It’s the fifth and final year of the Delaware Breeding Bird Atlas.
-A special effort is being made in 2012 to tally owls as part of the atlas.
Horseshoe crabs are being tallied again, and volunteers are being trained.
-The annual osprey count is offering a volunteer training for the first time since 2007.

Maryland is two years in to four years of surveys for an amphibian and reptile atlas and is looking for volunteers.

In Kansas, they are searching for lesser prairie chicken breeding areas, or leks, from the air with helicopters. Field crews will train on March 29-31 and conduct official survey work across all of western Kansas until the middle of May. The Kansas Department of Wildlife, Parks and Tourism is also asking people to report leks. The survey is part of a five-state effort, and the survey technique will be evaluated.

In North Dakota, the Game and Fish Department has launched a two-year study of white-tailed deer in intensely farmed agricultural areas.

In Maine, biologists at the Department of Inland Fisheries and Wildlife have visited up to 100 dens each winter for 37 years, making the survey in the nation’s oldest radio-collar monitoring program for bears. This year the Maine Sunday Telegram wrote a story about it, with lots of pics. Read it here.

And in Washington, commuters have been reporting wildlife sightings for over a year on the I-90 corridor in anticipation of road improvements. The project’s first annual report was released recently, generating articles in the Everett Herald  and The Seattle Times, and coverage other media.

Photo of I-90 Wildlife Watch billboard by Paula MacKay/Western Transportation Institute, used by permission.

“Smart” Collars Reveal Wildlife Secrets

A new type of wildlife tracking collar, using technology similar to a smart phone’s, will allow biologists and other wildlife managers access to the most intimate details of an animal’s life. However, the article quickly goes beyond the benefit this collar would be for wildlife research, and into the realm of managing human-animal interactions.
For example, the collar can tell scientists how long it’s been since a mountain lion has eaten, and if that mountain lion has entered a suburban neighborhood, allowing them to alert residents.
The New York Times article on the new technology ends with a snappy quote about being able to make a Facebook page for each animal, but it does not address any of the ethical or philosophical questions these collars raise.Which animals will be tagged? All animals in a region? Only those that have caused trouble before? Will new hunting regulations be created for these knowable, findable animals?

No news on either a timeline or a price tag is included in the article.

Read the story here.

Are you missing a mountain lion?

Chesterfield, MO

Are you missing a mountain lion? Missouri has it. Sort of.

There have been six confirmed mountain lion sightings in Missouri since November. One of the mountain lions, photographed on a trail camera in December, appears to be wearing a radio collar with a VHF antenna. While that suggests the mountain lion’s participation in a tracking study, Missouri Department of Conservation resource scientist Jeff Beringer has not been able to find the researcher who collared it.

“I have made a lot of calls to other states trying to identify that animal, but so far my only lead is a missing, collared, sub-adult male from Utah. That would be one heck of a move – but not impossible,” said Beringer in a recent press release.

Two of the other Missouri mountain lions were shot by hunters. Their DNA has been tested, and shows that they are from either the Black Hills of South Dakota or from northwestern Nebraska, which are the two closest wild populations of mountain lions to Missouri. There was no evidence that the animals had been held in captivity. Those mountain lions were young and male, which is consistent with the department’s theory that these animals are traveling into Missouri from their home areas. Young male mountain lions are known to travel long distances in search of their own territory.

Linn County, MO

Much more information is available from the Missouri Department of Conservation. It includes the press release with information about the DNA results (in the middle of the page, after the DNA results from a Great Lakes wolf found in the state).And background information on mountain lion sightings in the state, including a map.

Photos: Courtesy Missouri Department of Conservation. The Linn County animal is the one with the radio collar. Go to the original photo accompanying the press release for a closer view.