White-tail-deer

http://www.centredaily.com/mld/centredaily/sports/11925836.htm

Data reveal habitat remains key for deer at Raystown Lake

By Mark Nale

For the CDT


"It's the habitat," said Raystown Lake biologist Jeff Krause in a recent phone interview.

Hunters might find it hard to believe but even after all hunting and winter mortality, some areas of the open-to-the-public Raystown property still have more than 40 deer per square mile.

Krause recently received the data from the U.S. Army Corps' early April aerial deer survey, the second infrared study to be conducted on the Raystown property.

"Here at our Raystown Lake property, the results are clear," Krause said. "Where the deer numbers are the lowest it is more the result of the habitat than the hunting pressure."

In other words, where there is food, there are many deer -- little food, few deer.

The U.S. Army Corps of Engineers manages Lake Raystown and the 20,616 acres that surround it. The habitat varies from agricultural to mature hardwood forests. The Corps engages in timber management and habitat improvement each year.

Due to the excessive deer damage that had occurred in recent years, last fall, the Army Corps contracted with Vision Air Research to conduct an aerial survey of the entire Raystown Lake Project. The same company was used to do a follow-up survey on April 5. During both studies, VAR used forward-looking infrared imaging to detect and count all of the deer on almost all of the 32 square miles of the Raystown Lake Project.

The first aerial survey occurred on the night of Nov. 26, 2004, just two days before the opening of Pennsylvania's concurrent deer season.

Vison Air Research located 518 different groups of deer, with a total deer count of 1,636. According to Krause, this results in an average of more than 51 deer per square mile, but the density varied greatly by areas. The Raystown Lake Project is divided into 18 land management compartments. Last fall, the deer density varied from a low of 18 deer per squar mile in compartment 3 to a high of 80 deer per square mile in compartment 10.

Krause noted that this spring's survey located an average of 24.4 deer per square mile, about half the number found last fall. Once again, the deer density by compartment varied. Compartment 1, on the east side of the lake, had 73 deer per square mile and compartment 18 on the west side had only 5 deer per square mile. Four of the compartments, all on the east side of the lake, averaged over 40 deer per square mile.

Krause noted that compartments 14-18 on Terrace Ridge, the west side of the lake, had much higher deer densities last fall than this spring. He surmised that this difference occurred because the deer were feeding on the large red and white oak acorn crop on the ridge at the time of the fall survey.

The Terrace Ridge areas have acorns some years, but little browse (less than a pound per acre) and little year-round food for deer. Last fall, four of the five west-side compartments had over 40 deer per square mile while all but one (compartment 15) carried fewer than 20 deer per square mile at the beginning of April.

Even more interesting, the numbers of deer in some east-side compartments actually increased for the post hunting season survey. The deer density in compartment 1 increased from 41 per square mile last fall to 73 per square mile this spring. In compartment 3, which Krause described as "some of our best habitat," the number of deer jumped from 18 deer per square mile last fall to 51 deer per square mile in the April survey.

As another indicator of how quality winter/early spring habitat attracts deer, Krause cited compartment 9, which is a large and very accessible area of good habitat near James Creek. Last fall, that compartment showed a high deer density of 41 per square mile, and this spring it has 48 deer per square mile.

Krause used the aforementioned good habitat/many deer, poor habitat/few deer examples to support his assertion that habitat quality, rather than hunting pressure, has the greatest effect on over-wintering deer numbers.

However, one needs to look at one compartment, number 8, to see deer numbers drop even without hunting. According to Krause, there has been no hunting on the 400-acre Juniata College lease for the past 20 years, but the deer density decreased by 50 percent to 30 deer per square mile even without hunting. The deer simply moved to areas with better winter habitat.

Krause also said that in 2004, 850 Deer Management Assistance Program antlerless deer permits were issued for the Raystown property -- up from 450 in 2003. According to hunter reports filed with the Pennsylvania Game Commission, 250 of those 850 hunters harvested an antlerless deer last fall or winter, a success rate of approximately 29 percent.

Even with the high number of DMAP antlerless deer tags, the Lake Raystown Project deer herd is still too high in most areas. New fawns were born primarily after the April 5 aerial survey. Depending on the age and sex distribution of existing herd, and this spring's deer reproduction could easily make up for the number of deer harvested last fall. If so, the deer densities might be right back where they were before last fall's concurrent deer season. Krause would like to find out.

"Ideally, I'd like to have new aerial surveys done in November 2005, and again in late winter/early spring 2006, but with budget limitations I'd take fall over spring," he said. "I'd like to get a handle on whether the deer herd is decreasing towards our target of 15-20 deer per square mile or not."

Krause has seen enough to know that he needs to request a higher number of DMAP permits.

"We'll probably request about 1,000 DMAP tags for fall 2005," he said.

If all of this data has you overwhelmed, trust that Krause has spent many hours studying it, and he will continue to spend more time crunching the numbers and comparing them to last fall's. His goal is to better manage the Raystown Lake property for the benefit of all wildlife.

Krause left me with the following overriding message.

"At Raystown Lake, deer numbers dropped significantly in the areas with poorer habitat even though they were not accessible and were subjected to very limited hunting," he said. "The lake's better habitat areas still have higher deer numbers, even though they are often the most accessible and had the highest hunting pressure."

This is something for all hunters to ponder between now and next fall.

Mark Nale, who lives in the Bald Eagle Valley,is a biology teacher and member of the Pennsylvania Outdoor Writers Association. He can be reached at [email protected].

PABowhntr

Interesting comments and I seem to remember reading about them in another piece that was posted on here in the last few days. I would love to speculate on how some of this info. will influence hunter location come next fall.

PA GOBBLER

okay i live only 30 mins away.. i fish down there a lot.. but never hunted or even been into the woods around the lake.. now where they say all the deer are is where hunter access is the most.. does anyone know if this access is year round or the day before gun season or the week before.. i would love to go there and scout it out and bow hunt it. but i know places around my area that have access, well they dont open the road till a few days before the first day of gun or the nite before.. its hard for people to scout an area and find a nice place in that time..

BTBowhunter

If the deer densities can get that out of whack based on food sources, just imagine what kind of results they'd get if they did this on the first few days of rifle season! No wonder some hunters see no deer while others see plenty!

I'd like to see more of these done but I suspect the results would be similar in many places.

model99er

Speaking of results, anyonehappen to have a clueas to when PA's DNCR is ever going to publish the rest of their FLIR results ??


99er

White-tail-deer

I know we see it in my neck of the woods (5B), one farm will be over run with deer with the next farm asking where are all the deer?