"Before agreeing to work with John I was warned by a past assistant that he works his assistants hard, but we could never work as hard as he does, and I came to agree with that quickly," said Frank Castelli, a doctoral candidate at Cornell University who worked with Hoogland in 2003.
"Working with John showed me a level of passion that one must have to study organisms," said Castelli, who still hears from Hoogland a decade later. "I frequently seek his advice and he readily provides it."
Hoogland was still a young scientist when he made a disturbing discovery. When a mother dog left her burrow in search of food, other prairie dogs would invade her space.
"Then they would come up and lick their claws in a special way and sometimes they would have bloody faces," he said. "We thought, 'gee whiz, is it possible they are killing those babies down there?' Then we found that when the mother came back her behavior changed immediately. Instead of being aggressive and defensive, she just stopped defending that burrow and would start sleeping somewhere else almost immediately.
"So we thought there was a marauder down there killing babies," he said.
For a couple of years the researchers tried to dig down every time they witnessed an apparent homicide to find what had happened, but the digging was slow -- burrows are often 15 feet deep -- and by the time they dug deeply enough there wasn't anything left. The burrows, of course, are full of tiny parasites that can destroy evidence in a matter of hours.
So in 1984, Hoogland returned to the site with a new tool: a backhoe. It didn't take long to unearth the evidence he had been seeking.
It doesn't happen every year, he said. It depends on the availability of resources. In a good year, the clan can enjoy the benefits of living in a colony: mutual grooming to remove fleas, lice, ticks and mites; additional paws to dig the burrows, which can be 60 feet across and provide protection for the entire colony; sounding an alarm when a predator nears; communal nursing to improve the chances that more pups will survive.
However, the odds of surviving are not in the prairie dog's favor.
Hoogland is encouraged by the growth of organizations like the Prairie Dog Coalition, which consists of "thousands of people who donate their weekends and their time to trying to save prairie dogs." And there is growing support within the scientific community.
"In the last 10 to 15 years, biologists have realized that the prairie dog is a keystone species," as prey as well as predator, and "if we get rid of prairie dogs, the West as we know it is going to be a very different place," he said.
Incidentally, Hoogland carries out his work by observing the animals in their natural habitat, not dissecting them in his lab to see what's inside. The closest the animals come to that is being captured, splattered with a little paint for identification, and released.
Hoogland also took his wife, and his four kids, on those cold five-month excursions into prairie dog land. He's still married, and his kids are grown, but none became scientists. Maybe they read his scare letter.