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• Q: Can you please shed some light on the subject of doe urine as a scent attractant? A friend of mine claims that there is no way that all of the doe urine that is bottled for use is from female deer. As he claims, there are not enough deer in captivity to fill all of the bottles out there. Especially the estrus scent, which [manufacturers claim] is collected during the estrus cycle. [My friend] says using your own urine can be as effective as using deer urine, because the urine in the bottle is a mix of who knows what.

Eric Gazdik, Marshall Township

HAYES: Hunters have been debating this for over a decade. It's understandable that humans -- with sight as our primary sense -- have difficulty comprehending the way the world is preceived by animals such as deer, which rely primarily on scent for survival and reproduction.

Karl Miller, a wildlife biology professor at the University of Georgia and member of the Quality Deer Management Association's advisory panels, writes in his essay "Deer Scent Communication: What Do We Really Know?" that with a single wiff of the air, "deer can recognize other deer, learn about the other deer's sex, dominance status, reproductive state [learn about] the presence of predators and locate food."

But can they distinguish the urine of a doe in estrus from a squirt of commercial "doe in heat" attractor scent or any other snake oil? And how can a visually oriented consumer tell what's actually in the bottle?

Perhaps the most definitive research on the doe urine debate was a 1997 article originally published in "American Bowhunter" magazine by its publisher Daniel James Hendricks. Since then, "Into the doe urine industry" has proliferated on the Internet.

"Maybe the reason that article has been around so long is there was so much research put into it," said Hendricks, now publisher of "Horizontal Bowhunter" magazine, in an interview this week from Glenwood, Minn.

During four years of research, Hendricks poked around commerical deer farms, badgered biologists, weighed statistics and attempted to separate fact from fiction concerning deer acctractor scents. His conclusions?

"The best results come from straight deer urine," he wrote. "... There is no increased benefit from products which are labeled doe in heat.' "

"Only 30 percent of the attractants tested [by one of his sources] get a positive response from deer."

"Urine collected from a single animal is more effective than mixed urine."

As for whether to believe manufacturers' claims of estrus urine:

"If each [commercially raised] doe comes into heat three times," he wrote, "if the rancher is able to determine the exact beginning and end of each heat cycle; if the animal produces the maximum amount of urine; if the rancher collects that maximum amount of hot urine; if the animal does not get bred, it will produce 54 2-ounce bottles of 'doe in heat' product per year, maximum. How many does at optimum conditions does it take to make just 1 million bottles doe in heat product? Where are all of these animals?"

In the 10 years since Hendricks posed the question, no one seems to have come up with a good answer.

"Not all companies make accurate claims about their products," he said. "They said they were collecting doe urine in the summer to make fall sales, and they they were giving their does injections to bring them into heat. I've talked with vets. They says the hormones are too expensive for them to do that. ... There aren't enough commerically raised deer in the country to bottle all the doe-in-heat urine that's being peddled."

Hendricks, a big game hunter for 47 years, says he's more likely to trust an attractor scent claiming to be 100 percent deer urine than one claiming to be urine from a single animal or, particularly, from a doe in heat.

Masking scents, such as those that smell like apples, are more likely to be more accurate in their claims, he said, "But you've got to be careful. If it's apples and there are no apples in the area, it's not natural and it's not going to work."

A deer hunter's best bet on scents, he said, is to try to eliminate them.

"Try to get a good scent-elimination program going," said Hendricks. "Hunt the wind. Stay downwind of deer trails. Be aware of what they're smelling and try to reduce your impact."