The varied thrush explosion

One of the things I enjoy most about writing this column is the feedback and "heads-up" I get from people who are keyed in to what's going on around them; like right now with this sudden appearance of what may be "lots of" varied thrushes.

From the phone calls and "Hey Jim...!" being stopped in the grocery store, at Divine Earth, and the library, where people are asking about these "orange birds in my backyard," it sounds as though the varied thrush had a banner year last summer - perhaps in our high forests, or north of here.

Normally, "our" varied thrushes don't migrate as such but move altitudinally, up and down the Cascades (on both sides). The ones we normally see here in the Sisters area in winter have a summer range above Dugout Lake, the upper slopes of Black Crater, and among the hemlocks and firs below the snow line of the Three Sisters. But judging by the sheer numbers of thrushes being reported so far, what we are seeing may be coming down from Canada, or perhaps even Alaska.

Norma Funai, one of the Sisters area premier birders who lives in the Indian Ford area, told me she has three varied thrushes in her yard gobbling up juniper berries. She says she rarely sees any in winter.

Norma also went to Cornell's ornithology Web site and learned that not only have the varied thrushes enjoyed a big summer population explosion; pine siskins and evening grosbeaks also had large families this summer.

These population build-ups are very much like the thousands of American robins that visit us each winter. They are not "our" robins, but strangers from the northern latitudes that spend winter here gobbling up our delicious juniper berries, currant and any other small fruit they can find.

Robins and varied thrushes are zoologically very closely related, and are, in fact, in the thrush family, Turdidae (Tur-dee-ah-dee).

If you look in the National Geographic bird guide for North America you will find four pages of thrushes. They begin with the Siberian cutthroat and contain 20 robin-like species. Among them is our very familiar American robin, Western and mountain bluebirds, hermit thrush and the subject of today's column, the varied thrush. They all have one thing in common: they can handle cold weather and many of them are ground-dwellers.

The male varied thrush is really a dazzler to look at; he looks somewhat like an orange meadowlark. The black bib is striking against the orange throat, black mask, and orange body plumage, with a gray back and orange wing bars. This time of year, as with most birds, they have not molted into their bright mating colors, but even as drab as some are, they are striking. If you happen to see one with more white than orange wing-bars, please make a note of when and where you saw it and call me, 541-388-1659, or send me an e-mail at [email protected]

northwestnaturalist.net.

I may meet up with someone doing research on this species; odd coloration and sightings will mean something to anyone studying them.

Most birds consume huge amounts of insects as nestlings, and the varied thrush is no exception. Like most thrushes, they also use a cup nest in trees, and prefer to raise their young higher up in the forests, just below the arctic tree line.

As soon as they leave the nest they transfer their interest in food from preying on insects to eating the fruit of low vegetation - such as mountain strawberries, mixed with what invertebrates they can scratch out of the forest floor debris. Thrushes are very good at scratching for food like chickens: scratch, scratch, hop back to see what was unearthed, gobble it up; scratch, scratch, hop back, etc., etc., etc.

Thanks to all of you who have let me know about this sudden population explosion of these beautiful members of the thrush family. With these exchanges I enjoy the world we live in a whale of a lot more, and I continue to learn.