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Sandhill cranes migrate through Flathead Valley

by MARGARET PARODI Flathead Audubon
| September 29, 2021 1:00 AM

Sandhill cranes are truly magnificent birds and are usually seen in large, awe-inspiring flocks.

They have a very distinctive loud, rattling bugle-like call that is memorable and are also known for their ritualistic dancing and leaping displays during the courtship and mating season.

Sandhill cranes have been around for a long time which is another reason that I find them so fascinating.

Fossils from the Macasphalt Shell pit in Florida have been dated at 2.5 million years. Geologic time!

Flocks of sandhill cranes move through the Flathead Valley in both spring and fall during their semi-annual migration. The small pothole lakes in the West Valley and Smith Lake area offer ideal places for feeding in adjacent agricultural lands and overnight resting at the ponds.

It is the only migration stop in this region and the wetlands are an important rest stop in their journey in the spring to nesting grounds farther north in Canada and Alaska and in their fall return to their winter grounds which include Bosque del Apache in New Mexico and Anahuac National Wildlife Refuge in Texas.

Some birds do stay here and nest although the majority go farther north. While the migration through our region is impressive, it does not compare with areas along the Platte River in Nebraska where in March, 500,000 or more cranes eat and rest while migrating to Canada.

They typically feed on corn and other grains in surrounding areas and rest on the sandbars along the river at night. This is also a time when the single cranes look for mates.

Sandhill cranes are one of the largest birds and can reach 46 inches tall with a wingspan of 77 inches and weigh 10.5 pounds.

They are a tall, heavy grey-bodied bird with a bare crimson forehead and white cheeks, a long pointed black beak, and long, thin legs and neck.

They have a very distinctive loud bugling call that can be heard at distance. The loud trumpet-like call is produced by the windpipe that coils into the sternum giving it a lower pitch, extra volume, and reverberations. Spring brings the courtship and breeding season.

They are known for their bowing, wing-flapping and energetic dancing and leaping.

This is often accompanied by calling. Sandhill cranes form bonds that last for life. However, if one dies, the other will find a new mate.

Nests are made in small wetlands, often in the water, using a variety of local plant material such as cattails, grasses, and reeds. Nests are quite large and are 4 feet or more in diameter.

Normally two eggs are laid and the incubation period is about a month. The young are called colts, probably because they can walk almost immediately. They are covered in a rusty brown downy fuzz and because of this the parents preen themselves by rubbing mud on their feathers so that they, too, take on a rusty brown-grey color.

Sadly, usually only one colt survives to adulthood. Sandhill cranes eat a large variety of food and are considered omnivores. They feed on land or in shallow marshes and eat a large quantity of seeds and grains, but also berries, tubers, small vertebrates and invertebrates, insects, snails and even small mammals.

Sandhill cranes live and breed in wetlands often surrounded by upland areas of bushes and trees. While the birds tend to be territorial and defensive during the nesting and breeding season, they typically become more social afterward and it is common to see large groups feeding together in grain fields or roosting together at night near wetlands in the late summer and early fall.

Colts accompany their parents to winter grounds and stay with their parents for 9-10 months. The colts reach sexual maturity in about two years and then begin to search for a mate. Breeding can start at 2 years, but is often later.

The life-span of cranes is 20 or more years, although one remarkable crane that was banded in Wyoming lived to be 36!

Sandhill crane populations are numerous, even increasing in number and are not currently threatened.

However, it is extremely important that their habitat is preserved, especially in areas they use for the essential resting and feeding during the spring and fall migrations. Lead poisoning from spent shotgun pellets can be a concern in some marshes that see heavy waterfowl hunting. Safeguarding areas through conservation easements, as was done in the West Valley, aids in the preservation of this splendid bird.

A public bird viewing area was included in this West Valley conservation easement. It is located north of Reserve off of West Valley Drive.

For more information see the Flathead Audubon website https//FlatheadAudubon.org.