Tuesday, February 14, 2012

SANDHILL CRANES THRIVE IN THE NORTHWEST

Sandhill Cranes (Grus canadensis) are among the more spectacular of North America's birds. They make up in large size, active behavior and impressive sounds what they lack in bright colors. Actually, they even have a bit of bright color, but what they really have going for them is numbers. Cranes gather in flocks, and the gatherings can be huge. In the Platte River valley of Nebraska in spring, up to one-half million cranes gather. This is a staging ground for their migration north to their arctic breeding grounds. Like geese, cranes remain in pairs and family groups and are intensely social.

They are not that common in the Pacific Northwest, but thousands of them migrate through the interior spring and fall, smaller numbers migrate up and down the coast and winter near the Lower Columbia River, and a few pairs breed in southern Washington and many more in the marshes of southern Oregon.

Sandhill Cranes are protected at national wildlife refuges much as waterfowl are, and their numbers are stable or increasing. The great majority are the small birds that have been called "Little Brown Crane." They breed in the Arctic and winter in the western states, but there are also breeding populations of larger migratory birds all across southern Canada and northern United States and resident populations in Mississippi, Florida, and Cuba.

With their long legs and neck and imposing red crowns, a pair of Sandhill Cranes present an impressive sight as they stride across open habitats. Throw in a few more, and they may interact with one another, especially in spring: jumping up in the air with open wings, grabbing bits of the substrate and throwing that up in the air as well. This is the famous crane dance, immortalized in Japanese paintings for centuries and perhaps the source of the extensive mythology surrounding these birds. All 15 species of cranes do it, and we get to see it in our Sandhills every year.

In the Northwest, the best place to see cranes in winter is at Ridgefield National Wildlife Refuge and the surrounding open country in Washington and on Sauvie Island in Oregon. Large numbers are present feeding, roosting, and flying around. Flock after flock may pass overhead on their way between feeding and roosting grounds, their sonorous calls announcing their presence.

Cranes are true omnivores, with the predilection to eat just about anything found in the course of their foraging. Berries, seeds (including cultivated grains), and tubers make up the majority of their plant food, while insects, crayfish, amphibians, reptiles, and even small birds and mammals round out their animal diet. Nestling birds are a favorite, and open-country nesters such as Red-winged Blackbirds vigorously mob any cranes that come near their nest.

Migrant cranes can be seen in great numbers from late February to early May in the Columbia Basin, and a good time to visit is during the Othello Sandhill Crane Festival at Othello, WA (March 23-25 in 2012). Check their website for details. Similarly, cranes move through in large southbound numbers in September. During migration, you can see flocks high overhead soaring on thermals just like raptors do. In that way, cranes are very different from geese.

For nesting cranes, plan a trip to the refuges of southeastern Oregon in May and June. Malheur National Wildlife Refuge south of Burns has quite a few, and you can also see them in the fields around Burns. Much rarer as a nesting species in Washington, there are a dozen or two pairs at Conboy Lake National Wildlife Refuge near Trout Lake.

A pair of Sandhill Cranes will construct a big shallow nest in a marsh and incubate their two eggs for about a month. They defend the nest and subsequent young fiercely, flying at all avian and mammalian predators that appear anywhere nearby. After hatching, the young are led away from the nest to optimal areas for feeding, and the parents stay with them and feed them until they are able to fly at somewhat over two months of age. The young remain in a close bond with their parents until they are nine or ten months old, then may leave and join another flock.


Dennis Paulson

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