Infrared shows more deer than thought in Maryland

November 18, 1992|By Frank D. Roylance | Frank D. Roylance,Staff Writer

On the infrared scanner, the whitetail deer lighted up like a white beacon against the forest floor, which appeared in blacks and grays.

"There's one laying down," said Natural Resources Police Officer Linda Gaulden, pointing to the video screen in the cockpit of the converted MedEvac helicopter. "There's smaller ones in the woods."

The infrared camera, mounted on the belly of the 15-year-old Bell Jet Ranger II, panned to the right as Cpl. Wayne Stallings maneuvered the craft some 700 feet above the Patapsco Valley State Park near the Howard-Carroll county line. Soon, several more images of ghostly white deer popped onto the screen.

Ms. Gaulden, 31, a 5-year veteran of the Natural Resources Police, sat in the chopper's left-hand seat, tracking the deer as they bounded through the woods, away from the noisy helicopter.

In infrared, the animals' body heat made them glow, making them as easy to spot as Rudolph on Christmas Eve. Viewed directly through the helicopter's windshield, however, the deer's natural coloration allows them to blend easily into the shadowy browns and grays of the woods.

The DNR's $100,000 Forward-Looking Infrared (FLIR) equipment was purchased three years ago with federal money received after Natural Resources Police assisted the federal Drug Enforcement Administration with a drug smuggling investigation.

It has been used mostly for spotting lost hikers, fleeing felons and poachers. But since last winter, the FLIR gear also has been adapted to the state Wildlife Division's efforts to monitor and manage Maryland's burgeoning deer herd.

Ed Golden, the division's forest wildlife supervisor, doesn't like to fly, but has been delighted with the results of the airborne FLIR surveys.

"I get excited about it because it just expands the horizons of what we can learn about these animals," he said.

For example, until last winter, rangers estimated the 3,500-acre Sweet Air section of the Gunpowder Falls State Park was home to perhaps 200 deer. The estimate was based on "spotlighting" -- shining bright lights onto a field at night, counting the eyes that shine back and dividing by two. The counts are then used to estimate the area's total population.

But early this year the Natural Resources Police air crew flew a careful pattern over the park at 1,000 feet, and videotaped everything the FLIR camera saw below. Wildlife managers then sat down to watch the tape and count the glowing white deer that stared back at them.

They counted 408, more than twice what wildlife officials had guessed.

"That's 165 deer per square mile, which is very high," Mr. Golden said. "Usually, you want 15 to 30 deer per square mile." The count also came before the female deer dropped their fawns. "That brings it up to 650 to 700 for the fall population," he said.

For years, farmers and some property owners near the park have complained about deer damage to crops and landscaping. Their complaints and the FLIR counts finally led to a proposal for a brief and tightly controlled shotgun-only hunt in January. A decision is due soon from the DNR. If approved, it will be the first hunt ever allowed in the Gunpowder State Park.

"In some parts of the state, sportsmen are telling us we're killing too many deer," Mr. Golden said. "We'd like to get them up there [with a FLIR survey] and let them see how many are left over."

Maryland's deer herd has been growing dramatically in recent years, aided by a natural adaptability, mild winters, abundant food, and suburban development that has curtailed hunting while preserving tree cover.

Estimated at 100,000 animals in 1980, the herd now numbers as many as 200,000, Mr. Golden said.

Mr. Golden would like to try out the airborne FLIR technology on the state's bear population. Black bear in western Maryland are multiplying, but no one has a good count.

FLIR also might provide wildlife managers with better counts of the state's imported Sikka deer population, and Mr. Golden says he might even try it out on turkeys.

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