Wednesday, February 13, 2013
SPOKANE — An ambitious research project is under way to shed light on the mysterious movements of white-tailed deer through the thick cover of northeastern Washington.
The study area in Stevens, Pend Oreille and northern Spokane counties covers the state’s most productive region for whitetails and the hunters who pursue them during fall big-game seasons.
About 35 bucks, does and fawns gave researchers an intimate glimpse of their daily movements, migrations and, in a few cases, their deaths during the first year of research that started in January 2012. Another 35 already have been captured, fitted with transmitters and released during the winter trapping season going into the second year of the study.
About $400,000 in federal grants, state wildlife funds and volunteer services will be devoted to the project over 3 1/2 years, said Woody Myers, Washington Fish and Wildlife Department big-game research biologist.
Up to 100 deer will be adorned with $170 radio ear-tags or with $2,200 GPS collars that allow researchers to peg their location every four hours. Deer movements can be overlaid on maps that will show their migration routes and habitat preferences.
The number of deer with transmitters was small as the study ramped up in its first year, but some trends already are catching the attention of Myers, and University of Montana researcher Charlie Henderson.
“It’s somewhat surprising to see how far some whitetails were migrating from summer to winter ranges,” Myers said. “The Midwestern and Eastern version of whitetail research shows whitetails with fairly small home ranges, just a few square miles. But we’re seeing some whitetails moving farther.”
One deer stayed within 393 acres — about a half-section of land — for the year.
However, the largest home range (year-round area) documented so far is 7,633 acres covered by a doe. She concentrated most of her summer on 563 acres and wintered on 755 acres.
“As a storm was moving, the doe headed to her winter range as though a light came on,” Myers said. “She left her summering area near the Pend Oreille River at 2 a.m. on Dec. 19 and arrived within her winter range on the Little Pend Oreille (National Wildlife Refuge) on Dec. 21. That’s 20 miles as the crow flies.”
Some deer followed the same corridor almost exactly as they came to winter range and returned to summer range in the spring. Others varied their migration patterns.
The main research and parallel studies could help wildlife managers set hunting seasons and regulations and focus habitat improvements to boost the region’s deer.
Based on their perception that northeastern Washington was short on mature bucks, Stevens County sportsmen prompted a controversial rule two years ago restricting most hunters to killing only bucks with four antler points or more in the popular Game Management Units 117 (49 Degrees North) and 121 (Huckleberry).
State wildlife biologists didn’t support the restrictive regulation approved by the state Fish and Wildlife Commission, but they acknowledged they didn’t have an abundance of local research data to take a stand one way or the other.
Research is under way seeking to estimate the northeastern Washington whitetail population. One of the techniques involves going into designated areas with dogs trained to sniff out piles of deer scat. The number of scats per site is figured with analysis of samples to peg how many different deer are using the area.
“Whitetails aren’t as easy as elk to census by aircraft, especially in northeastern Washington,” Myers said. “We have to be more creative.”
College students from as far as Missoula are involved in the studies, and North Central High School genetics lab students are doing DNA tests from blood samples.
Contributing to the research are biologists from the U.S. Fish and Wildlife Service and the Spokane and Kalispel tribes. Two private timber companies and the Colville National Forest are giving researchers special access to closed forest roads in some areas.
Researchers also are using ultrasound on trapped does and collecting road-killed deer to check for fetuses, which they can measure to determine the dates of conception.
Generally, deer benefit from having enough bucks for a concentrated November breeding period so fawns hit the ground in a short period in early June. Predators will kill fewer fawns if they are born within 10 days than if their births are scattered over weeks.
On the other hand, late breeding of female fawns would be a good sign that deer are finding proper nutrition, putting on weight and becoming sexually mature earlier than normal, Myers said. Most bred females are yearlings or older, he said.
The study is enlisting the help of roughly 70 volunteers, mostly from the Inland Northwest Wildlife Council as well as from colleges, Myers said. Groups are trained to help trap deer and then monitor movements of the radio-tagged deer from the ground.
The Stevens County Fish and Wildlife Committee was particularly helpful in gaining access to private land for trapping the deer, Myers said.
Deer trapping is hard, dangerous, time-consuming work carried out by volunteers who are donating $40,000-$80,000 of service time a year to the study, Myers said.
The traps, which resemble portable dog kennels, are placed in secure areas such as farms where they can be baited and monitored. When a deer is caught, volunteers show up within hours and collapse the cage to immobilize the deer so it can be blindfolded and hobbled.
In one case last year, two cougars attacked and killed a deer in a trap just before the research crew arrived.
“Apparently one cat reached through the mesh with its paws, pulled the deer close and killed it by biting its head,” Myers said. “A single canine (tooth) punctured its skull into its brain.”
None of the collared deer was shot by hunters during the fall season. About two-thirds of the deer collared so far are females plus several sublegal bucks
Harvest of antlerless whitetails in units 117 and 121 is limited to youth, senior and disabled hunters during a four-day window in the season and bucks must have at least four points on one antler to be legal game. Those limitations plus a small sample size in the first year of the study lowered the probability that a marked deer would be killed by a hunter or a wolf, he said.
Survival rates of adult and juvenile deer and causes of their deaths are key goals of the research, he said.
Each deer is weighed, examined by a biologist who takes a blood sample for various tests and DNA. Deer released with radio-ear tags must be monitored by volunteers who go out on the ground and from occasional aerial surveys.
Some deer get the more expensive GPS collars, so they can be tracked by satellite from Myers’ computer or mobile phone.
One GPS collar has malfunctioned so far and a few of the ear-tag radios have dropped out as the deer go about their lives in the brushy wild. Overall, Myers expects to get two years of tracking out of each transmitter.
The GPS tracking is so accurate, the research should reveal details such as how often deer are on north-facing slopes, in farmers’ fields, near roads or what age of forest clearcut they prefer.