Much to consider when tracking deer numbers
Habitat change one reason for shifting levels
Joe Wilkinson
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http://www.press-citizen.com/article/20110210/SPORTS05/102100338[/FONT]
[FONT="]It's hard to hide on a blanket of fresh snow. Even from 500 feet, a deer sticks out like a sore hoof as it is counted by surveyors on high.[/FONT]
[FONT="]"You count the deer bedded down there in the woods or other cover. On a really cold morning, they are going to stay right there. You usually see their heads turn to look at the airplane," said Tim Thompson of the Department of Natural Resources wildlife biologist.[/FONT]
[FONT="]Those aerial surveys commence after deer season closes, conducted after fresh snowfall, so the deer are more visible. Around here, most counts are done. A few helicopter forays into urban areas still may come. Results from 300 aerial looks help determine postseason deer populations, as wildlife officials look ahead to future seasons and manage the state herd to get it back to 1990s levels.[/FONT]
[FONT="]Taken alone, a count here or there will raise eyebrows. In Linn County this winter, surveyors tallied 80 percent more deer than on the same route a year ago. Yet the DNR and hunters have been claiming the numbers are down. So what gives?[/FONT]
[FONT="]The habitat.[/FONT]
[FONT="]"A lot of things change year to year," Thompson said. "That route follows the Cedar River up into Black Hawk County. There was a lot of fall tillage, former CRP land, even fence lines have been pulled out (and put into row crops) because of high crop prices. There's less cover outside the survey area. That concentrates more deer in the river corridor."[/FONT]
[FONT="]That could explain a big one-year jump. Along the English River, in Washington County, Thompson's crew counted 60 percent fewer deer. Yet they don't really expect the true deer numbers are down quite that much, either. On four other routes, through Johnson County, one was basically the same. The others were down.[/FONT]
[FONT="]Most hunters, particularly in east-central Iowa, report seeing fewer deer than in years past. I have seen noticeably fewer deer here around the northeast end of the Coralville Reservoir before -- and now after -- the season. Although hunter comments are considered, biologists rely more on the science of deer management before making recommendations on special seasons, urban hunts and numbers of county tags.[/FONT]
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[FONT="]"We fly the same transects, year after year, under similar conditions," Thompson said. "We also factor in the reported deer harvest, road kill data, bowhunter surveys and a spring spotlight survey. You can't look at pure numbers. You have to balance all the indices."[/FONT]
[FONT="]With that framework, biologists set up guidelines for the next season. Getting a close look before fall will be the successful county-specific antlerless tags. They have done well to increase the doe harvest. That, in turn, translates into fewer fawns coming into the population in the coming years. Too many deer? Offer more tags. Numbers dropping? Then reduce the tags.[/FONT]
[FONT="]You can expect continued adjustments with the January late season, as well as the "Thanksgiving weekend" hunt. Each targets antlerless deer. In counties near their population targets, hunters had fewer chances to buy antlerless tags in those special seasons. Expect fewer yet in the coming year.[/FONT]
[FONT="]Recommendations from wildlife biologists go to the state Natural Resources Commission in May.[/FONT]
[FONT="]Reported deer harvest down[/FONT]
[FONT="]Iowa's reported deer harvest shows a drop over 2009-10 levels -- a reflection of the computer models showing drops over much of the state in the last few years.[/FONT]
[FONT="]Hunters are required to report any deer they harvest, either by phone or online. Several days after the Jan. 30 close of Iowa's latest seasons, that harvest number stood at 127.094, down from about 136,000 a year ago. The number of does taken was 65,196, which would be the sixth consecutive year in which female deer outnumbered bucks.[/FONT]
[FONT="]Clayton County in northeast Iowa ranked shows the highest harvest (4,856) with Van Buren (3,768), Warren (3278) and Allamakee (3,243) finishing two, three and four. Hunters in Johnson County reported taking 2,320 deer during the 2010-11 seasons, 11th highest in the state.[/FONT]