Subject: More "yard-owl" notes
Date: Feb 22 15:37:37 2004
From: Kelly Cassidy - lostriver at completebbs.com


My resident Great Horned Owls are not as outgoing as Harry, the Yakima owl. Mine are a pair that hang out in a spruce tree near the house. They've had hooting duets since about November. Hooting frequency has intensified the past few days. They've been hooting at midday on sunny days. Hormone overdrive, I suppose. Three days ago, I heard a pair of Barn Owls screeching, one flying and one perched. It gives me hope that the Barn Owls will accept my nest box as a substitute for the barn we tore down last summer, but they face a lot of competition for the vole supply from the Great Horned Owls.

Last week, I scanned through a 1973 WSU thesis by Joseph Foster on Great Horned Owls breeding on the Palouse. According to Foster, GH Owls depend heavily on Red-tailed Harks for nests. GH Owls do not build their own nest nor do they do any upkeep on the nests they take over. Foster says Red-tailed Hawk nests used by GH Owls are usually in such a state of disrepair the nests are unusable after a year or two. No Red-tailed Hawk or Raven (whose nests GH Owls also use) has nested in my yard since I've been here (2 years), so it is a mystery to me where the owls intend to lay eggs. A pair of Red-tail Hawks have nested for two years about 1/2 mile away. Maybe the owls intend to take over their nest. According to Foster, the owls don't care if the nest builder still wants to use the nest. The GH Owls move in and take over. Palouse GH Owls usually lay eggs from about the second week of March to mid-April.

The Magpies are distraught over the owl presence, but, compared to crows, Magpies seem to be ineffectual owl-harassers. The Magpies nested in a row of shrubs about 200 feet from the owls' favorite perch tree last year and have indicated an interest in nesting there again. According to Foster, owls eat mostly rodents and a few rabbits, but among the birds they ate, Magpies seemed to be disproportionately represented. The Magpies are justified in being upset. Perhaps the Magpies will nest somewhere else? The Robins would be relieved if they did. Blue Robin eggs decorated the yard last year, apparently courtesy of the Magpies.

Other signs of spring:

Robins passing through in hordes, but not singing yet except for weak semi-songs.
Song Sparrows singing
House Sparrows chirping like mad all day, also trying to find suitable nesting locations to replace their beloved old barn
House Finches reappearing from their feeder hangouts in town.
Gray Partridges clucking more frequently
A Northern Shrike I've seen several times this week, singing away. (Actually, almost every time I've seen a N. Shrike this winter, it's been singing. What's with that?)
Killdeer and RW Blackbirds reappeared 3 days ago.

Kelly Cassidy
Pullman WA