Crew peeks into burrows to keep track of declining species

By ANNA KING
Tri-City Herald

KENNEWICK, Wash. -- Mark Southern often lies down on his stomach in the dirt alongside roads.

He says the behavior may raise eyebrows, but he assures the public it's his job. He's studying the elusive and dwindling population of burrowing owls around the Tri-Cities.

Southern serves as the field crew leader for a team of scientists. His job includes carefully snaking a long garden hose-like tube down the small openings that mark burrowing owl nests.

He wears a pair of infrared goggles and places a dark pillowcase over his head to shield his eyes from the sun so he can better see the infrared images. The goggles and the video camera tube are part of a specially designed device called the "peeper" that weighs about 20 pounds.

"It's good for building muscle," he said as he hauled it around.

On this particular afternoon outside Pasco, Southern groaned as he pulled the equipment out of a hole. He said he couldn't tell if there was in fact a clutch of eggs or juvenile owlets inside. A dust-colored adult male warily watched from atop a nearby cyclone fence in the undeveloped area near a new neighborhood.

With Southern were Courtney Conway, the lead wildlife biologist on the project, and Jonathan Hogg, a field technician. The trio traipsed out early that morning trying to spot some of the hard-to-find owls.

Each spring and summer, these scientists or others from their group descend upon the Tri-Cities and the Othello-Moses Lake area to check on the tiny burrowing owls that come to the region to raise their young and spend the summer months. The birds' population is believed to be declining.

The owls stand not much taller than an unsharpened pencil and nest in the abandoned burrows of other animals like ground squirrels, badgers and skunks. In the Tri-Cities, the owls' decline is thought to be partly caused by burrow destruction from rapidly expanding development and destruction of their shrub steppe habitat.

Jumping in and out of a battered white jeep, Southern, Conway and Hogg lugged the peeper, binoculars and notepads out into the brush and sand to try to record leg band numbers and other features of the skittish owls.

"There are about 400 holes in the ground that we monitor," Conway said.

Those holes are within a 120- square-mile range the scientists survey where owls have been known to nest.

This year, there are about 66 occupied burrows, and owls in only 43 of those burrows have successfully raised young. Usually, the number of occupied burrows found in the Tri-Cities area hovers around 100, Conway said.

Once scientists figure out where the owls have chosen to stay, they monitor those burrows more intensely.

But finding occupied burrows is tough. The scientists have to get up early and stay up late. The owls typically hide underground during the hot part of the day and forage and sit outside their burrows during the dawn and dusk hours, Conway said.

"If you want to know what your hours are going to be, even for the next week, this isn't the job for you," he said.

This year, Conway said, it seems like fewer burrows have been occupied than ever before. And owls in about 16 burrows have failed to successfully raise their young.

"We're a little concerned," Conway said. "Of course, all animal numbers have ups and downs. It will be important to watch what happens next year."

Trying to tell where the owls are, how many young they have, if any have been eaten by predators, if the parents have incubated two clutches of eggs and if the pair have stayed faithful to each other becomes difficult to tell.

"It is like a soap opera because it's a family life," Conway said. "Each burrow is like a puzzle. Because they live underground, each visit only reveals a tiny snippet of what's happening 10 feet below ground."

When the scientists walked a short distance in the Pasco field to visit another burrow, several owlets were hiding underneath nearby sagebrush. The owlets' father kept a close watch from the roof of an abandoned car as the babies bobbed their heads up and down and looked back at the intruders.

Other than flying away or making a little hissing sound imitating a rattlesnake, the owls, even the adults, are mostly defenseless.

Only about 5 percent of the juvenile owls return to the area, Conway said. That could be because of high death rates or because they choose other areas to nest away from their home burrows. The scientists have found several juvenile owls from the Tri-City area near Moses Lake the following year.

"They want to get out and party," Conway said, joking.

A more likely conclusion is that the parents already occupy most of the choice nest sites and the juveniles need to find other places to live.

Bumping along in the Jeep to different sites, the scientists occasionally slowed the vehicle and scoped out some of the sites with binoculars. Sometimes the owls stayed by their nests if the trio remained in their vehicle.

Thick black tape pasted a sheet of paper onto the Jeep's headliner. On it was scrawled in black letters, "Most Wanted." It listed the burrows where owls had continued to escape identification.

Investigating another burrow, the scientists noted a scattering of pellets, feathers and owl tracks near the burrow entrance, indicating the burrow was being used. Crumbling apart a pellet, which is a regurgitated ball of indigestible material, with his thumbs, Conway showed how they are like tiny hairballs filled with minuscule bones, insect legs and other debris. The owls spit them out after eating.

Other burrows were noticeably abandoned, spider webs covering their entrances. Some owls switch burrows, making tracking them even more confusing.

Just this year, several burrows have been lost. One with a mating pair and eggs was plowed through by workers installing a utility line. One was sprayed with herbicides, and others have caved in from being run over by vehicles or from natural causes.

Many of the burrows the team visited this morning were within steps of major roads, farms, housing developments and trains.

Efforts to create artificial burrows to replace some of those lost only help so much. Bird enthusiasts have created about 230 artificial owl homes in the Mid-Columbia, but only about seven were used as nests.

"The idea was a Field of Dreams approach -- build it and they will come," Conway said. "That's not exactly what happened."

Conway believes the artificial burrows weren't very successful because the owls need a food supply nearby. He estimated most of the owls find their favorite foods like insects, small rodents and the occasional small bird or bat within about a quarter-mile of their burrow.

Sometimes landowners become so protective of the owls they won't even allow the scientists to study them, Conway said. He said he appreciated the protective attitude but said the studies are meant only to help the owls.

Conway studies burrowing owls in Washington, Arizona, Wyoming and Mexico, but is permanently based in Tucson, Ariz. He is paid by U.S. Geological Survey. Grants pay for his field research crews, who do most of the day-to-day trapping, banding and recording of owl activity. Other financial assistance comes from other state agencies that donate vehicles and housing for the team.

The birds are listed as endangered in Canada and are being bred in captivity there to bolster their numbers. Two out of the four provinces where the owls were once found no longer have burrowing owls, Conway said.

He said there are enough owls in Washington state now to maintain a good population, but the population could suffer if something isn't done soon to preserve habitat, he said.

"Now's the time," he said, "instead of waking up 10 years, five years or one year from now and putting them on the (endangered) list."