Monday, March 23, 2009

From Dusk 'till Fawn

This column was originally written in August 2008.

A few weeks ago, Brent Howze needed my help finding white-tailed deer fawns with a $12,000 heat-detecting camera before coyotes or bobcats got to them first. Although it meant a late night, I agreed to give it a shot. Brent is a University of Georgia graduate student and he’s studying fawn mortality; by capturing newborn fawns and monitoring their activity, he can determine the influence of predators on deer populations.

Historically, panthers and red wolves patrolled the southern pine forests, eating and outcompeting smaller predators such as bobcats and raccoons. When these big predators became locally extinct due to overhunting and habitat loss, the smaller predators increased in number as a result. Also, coyotes invaded from the west, taking over the niche previously occupied by wolves.

For many years, smaller predator populations were kept down by trappers after their fur. But over the last few decades, both interest in this activity and demand for fur has steadily decreased, resulting in higher numbers of raccoons, bobcats, coyotes, etc. This isn’t necessarily a bad thing, but wildlife biologists are eager to know how these changes have affected the ecosystem.

That’s where Brent comes in; this time of year does often temporarily leave their fawns behind as they graze for food. Fawns are virtually scentless and highly camouflaged, their primary defense is to lay perfectly still in the grass. But they still give off heat and Brent has a secret weapon to exploit this.

At night, Brent hooks up a television to his truck’s battery and places the tv in the bed. To the television, he plugs in his heat-detecting thermal camera, an expensive piece of equipment. Images from the camera are transmitted onto the television for easy viewing. Pointing the camera in the dark night reveals a hidden world.

The outlines of trees, rocks, and bushes are various shades of gray but easily distinguishable. The warmer an object is, the lighter it appears. The camera is so sensitive that we can easily make out rats and mice hiding in the weeds, their body heat causing a bright white ball to appear on the screen.

I thought my job was to drive the truck through the woods while Brent kept a close eye out for any white blob that might be a hidden fawn. He quickly informed me of some additional duties: if he saw a fawn, he’d alert me and I was to stop the truck and jump out with a giant net. Brent would guide me towards the fawn by viewing my progress on the television and at his cue I’d pounce forward, hoping I could capture it before it bounded away. Once captured, the fawn would be fitted with a radio collar, allowing Brent to keep an eye on it with an antenna. I solemnly acknowledged my responsibilities, adjusted my head lamp, and put the truck in drive.

I slowly navigated the dirt roads, occasionally distracted by a miniature screen in the front seat that allowed me to view through the camera as well. It wasn’t long before we both noticed three white blobs in the grass. What is that? I heard Brent mutter. Some quick birdlike movements and the animals revealed themselves, a covey of bobwhite quail. We drove on.

Then there were several armadillos, their turtle-like shell was immediately recognizable as the unusual creatures shuffled across the ground looking for insects and grubs to eat. When we first spotted a deer, its form looked gigantic compared to all the small critters we had seen. Brent flicked on his 500,000 candlepower spotlight; the doe was illuminated only about ten feet from the truck but we never would’ve had a clue it was there without the thermal camera.

Unfortunately, the doe was without a fawn nearby, a trend that continued through the night. Although we spotted nearly 30 deer, they were all adults or nearly so. One huge buck lay in the grass a few feet from the road; its broad, velvet-covered antlers included a drop tine. After briefly viewing him with the spotlight, he lazily rose to his feet and slowly sauntered off. He might make some hunter happy this fall.

A successful capture from a previous effort
At about 11:00 we briefly saw three or four large shapes through the camera. By the time I slowed the truck and backed up to a better vantage point, the shapes had quickly slinked away into the night. They were gone before we could get a good look at them. Coyotes, Brent told me. They are fascinating animals, in the west this species is relatively small and solitary but as they’ve expanded their range eastward their size and behavior has shifted. They’re larger here, which enables them to hunt larger prey. It’s almost as if they’re acting like the wolves that used to be found here.

At midnight we called it quits, the night was a bust for catching fawns. But we know they’re out there, the next day Brent found some coyote scat and on closer inspection (a particularly unglamorous part of his job), he noticed a pair of small hooves in it.

No comments: