As hunters and the Pennsylvania Game Commission sort out the results and recommendations of the Wildlife Management Institute's audit of the state's deer management plan, a separate report seven years in the making sheds light on controlling deer populations on a smaller scale.

The U.S. Army Corps of Engineers manages 8 million acres of land nationally, including 22,000 acres of forestland and fields surrounding Raystown Lake in Huntingdon County. The Corps reversed a growing habitat problem, said staff biologist Jeff Krause, and increased opportunities for hunters by bringing deer numbers and habitat into balance.

Krause will explain how Raystown solved its deer problem, and surprising ways that hunting impacts deer densities, at a free seminar 7 p.m. March 22 at the Richland High School in Johnstown (814-659-1280).

"When we started forest management in 1998-99, we saw a lot of browse impacts," said Krause, who has managed wildlife at Raystown for 14 years. "There was a lot of browsing well before that, but it became more obvious when we had plots of forested lands that weren't regenerating. We could see we wouldn't be able to have a forest management program without controlling the deer herd."

Each white-tail deer eats about a ton of shoots, twigs, leaves, weeds and grasses each year. Females reach sexual maturity in 12 months and the reproduction rate is high with does often bearing twins and sometimes triplets. The impact of deer on Raystown habitat was visible.

The Corps tripled the amount of road access open to hunters, but said Krause, "that wasn't going to be enough."

The real problem, they found, wasn't the number of deer per square mile, it was the imbalance between deer and vegetation.

"The number of deer in a given area tells you very little about whether the area can support more deer or if the deer need to be reduced," he said. "It depends on the quality of the landscape."

Krause said a mature forest with little sunlight reaching the ground and poor quality soil might have only five deer per square mile, but they've eaten everything up to the browse line.

"In a mixed landscape with a lot of edges, open areas, a lot of agriculture and small wood lots, you could have 20-30 deer per square mile and notice no impact at all, because there's so much for them to eat," he said. "At that time we had a missing understory, low diversity of plants, stunted seedlings that had been browsed for decades and a larger number of deer than the habitat could support.

The solution, they found, was learning more about the growth within individual landscapes and scaling the deer herd to that amount of forage.

In 2003 the Corps developed a deer management plan and enrolled in the Game Commission's Deer Management Assistance Program. DMAP was designed to help landowners with parcels of heavily hunted areas to manage deer and meet land-use goals, and offers additional opportunities for hunters.

A year into the program, a combination of post-hunting season aerial infrared deer surveys, spotlighting, pellet counts and habitat evaluations tallied 54 deer per square mile, with densities in some areas as high as 80 per square mile.

Antlerless allocations for the 4A unit that includes Raystown Lake rose from 37,000 in 2003 to 43,000 in 2004, then dropped to 29,000 by 2006. The Corps was granted an increase in its DMAP harvest. With fewer deer, an estimated 12 million new seedlings sprouted.

"By 2007 we were taking areas out of DMAP after they met our vegetation goals," said Krause. "From 22,000 acres, we now have 8,000 in the program."

After dropping the deer population in the first years of the program, diverse vegetation is back and surveys show the deer population is rising -- from a post-hunt 12 deer per square mile in 2008 to 15 deer per square mile in January. Last fall's pre-hunt estimate of 26 deer per square mile correlates with the deer audit's low-range estimates for 4A. Krause said the Corps is meeting most of its foresting goals, and wildlife diversity is increasing with increased numbers of turkeys, bears and songbirds. Last year a 32-mile bicycle trail opened at Raystown, bringing in more recreational tourism.

"You're not really managing deer," said Krause, "if you're not managing their impact on the natural environment, which ultimately will help the deer."

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