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Hooting and Hollering
We left the first pair in the deepening dusk. The male looked forlorn, as if, having dutifully delivered three juicy mice to his young, now he deserved one for himself. Mike assured me that the fact he’d hacked up a pellet (shortly after his mate) meant that he’d eaten well the night before. “You get no break today, buddy,” he told the owl.

We drove a little farther into the parcel and halted next to a small stream. At this site, Mike had spent several days tracking down a pair who led him on a merry chase through the woods. Only after dedicated pursuit did he manage to find their nest, which is near a tract due to be logged this year and only a couple hundred feet off the road. This habitat is more marginal than the first nesting stand, with younger and sparser trees. The fact that the road is so close to the nest is of concern as well. “If this were a main haul road,” Mike explained, “the U.S. Fish and Wildlife Service would say the owls knew what they were getting into when they nested. But for this one that doesn’t get used much, if all of a sudden you have ten big-deal trucks a day coming through, it might cause problems. I think what’s going to happen is that they won’t allow hauling until about the first week of July. And it’s up to me to make sure that if there are fledglings, they’re able to fly and get out of the way if they land on the road when a truck is coming along. Whereas most operations can start in June, this will just be put off a month. I’ll also make sure the nesting process is still happening. If the attempt failed, they will probably be able to haul earlier.”

From the fledglings’ first flight in early July, the parents have four to five months to teach them what they need to know to survive, before kicking them out of the nest by mid-October. “They’ll use feeding as a training session. They’ll almost play games, like ‘If you want it, you’ve got to follow me,’ and they’ll lead the juveniles through all this dense brush.” When it’s time for the young to be on their own, they’re some 20 percent heavier than their parents. This head start doesn’t guarantee success, however. “The data suggest that 80 percent or so of juveniles don’t make it through their first year. The key is the first winter: if they make it through that, their survival rate goes up to about 90 percent.” Part of the problem is territoriality--finding an area that isn’t occupied and that has sufficient forage. It’s an energetics issue as well, since they may have to fly long distances to find a spot that they can call home.

One-, two-, and three-year-olds often end up as “floaters,” with a very large home range but no defined territory. To claim a territory of their own, they typically have to wait for an opening--perhaps running an older male out of his territory or, in the case of a female, seeing if the male of a pair will take a fancy to her and abandon his mate. These newly disenfranchised birds then become floaters themselves. “They’re almost impossible to study because they don’t vocalize, since they don’t have a territory they’re defending.”

We spent half an hour more trying to attract the second pair with small-rodent noises (pursed-lipped squeaks) and the dry rustle of leaves, courtesy of a mouse tied on a string, as well as repeated contact calls. The male showed himself twice, but each time immediately disappeared into the thick forest with his mouse booty, so it wasn’t possible to verify whether the nest was still being tended. Mike would have to make a follow-up visit. “Even if they’re no longer nesting, they’re obviously roosting--it’s an area that they prefer. And knowing that is important.”

After mouse number two, Mike called it quits. Back in the truck, we creaked and rattled up the rough dirt road so I could observe the main part of his job: hooting or calling. Lasting much of the night and taking him to 15 to 20 stations a night, 75 to 100 a week, this activity helps Mike keep track of the resident territorial owls in the parcel, and of their range. Commonly for THP development, two-year surveys are required, with three calling cycles a year, at least one of which must be done after May 15; the other two generally fall somewhere between March and late July.

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