Idaho Falls Post Regiser, March 27, 2007.

Bill Schiess / for the Post Register - A
saw-whet owl at Camas National
Wildlife Refuge seeks cover in thick
brush during the daylight hours.

The 8-inch northern saw-whet owl at Camas National Wildlife Refuge has been drawing photographers and birders from around the West for the past four weeks. Tucked in against a tree trunk, it blends in very well with its brown and white plumage, resembling a bump on the tree.

"It was discovered by some birders about four weeks ago," said Rob Larranaga, the manager of the refuge. "I have never seen it fly, but it must hunt voles and mice at night around the headquarters."

Saw-whets are extremely nocturnal, leaving their perches usually only after dark to hunt. During the day, they roost in thick brush near the ground using their coloring as camouflage to hide. They do not flush easily, allowing people to walk within 2 or 3 feet of them without moving.

Very secretive and very small, they are hard to find and are seldom seen.

Their distinctive call lets people know they are around. Their call sounds like a saw being sharpened on a whetstone, giving them their name, saw-whet.

Another distinctive feature is that they vocalize only at night and during the breeding season from March through May. They remain silent the rest of the year.

Birders are reporting these owls actively calling in the Blackfoot area.

After they pair up, saw-whets find an old woodpecker hole and nest there. Being cavity nesters, they compete with starlings and other cavity-nesting birds. The large cottonwoods at Camas provide a lot of cavities for nesting, and saw-whets may be nesting at the refuge.

"Last year while working at Camas, I saw a juvenile saw-whet being mobbed by other birds," said Jake Briggs, a photographer and birder from Idaho Falls. "It must have been from a local nest, but I could not find the adults."

Song birds as well as magpies will mob saw-whets when they are located.

This is how Briggs located the juvenile.

"I thought the magpies were harassing a robin and went over to help it when I saw it was a saw-whet," Briggs said. "The juveniles are a rusty brown almost looking like a robin's breast."

The main prey for these owls is deer mice.

Perched on a branch near the ground, they hop on the mice and usually eat the head immediately and store the rest. They have been known to kill six to eight mice in a night.

During the winter, the stored portions of the mice will freeze. The owl will then "brood" or sit on the leftovers until they melt and can be eaten.

Due to their secretive nature, saw-whets may be undercounted and are rarely seen. Once located, they can cause a stir in the birding world.

"We don't know how long it will stay or how long it has been here," Larranaga said. "We just want people to respect it and not get too close, harassing it."