Somewhere in Maine, a few folks are about to get a big surprise. Nobody expects a sandhill crane to show up in their yard, until suddenly one does.
Sandhill cranes are about the same size and shape as great blue herons. They both have long necks and long legs. The similarity ends there.
Great blue herons nest in trees, often in colonies containing multiple nests. They feed almost exclusively on fish and other aquatic life, but they also consume insects, small mammals, and even small birds.
Sandhill cranes nest on the ground in marshy areas. They are omnivorous, and mostly consume seeds and grains, along with tubers and berries. They may eat small vertebrates and invertebrates, but generally not fish. This explains why cranes start surprising people at this time of year, as they move out of the marshes and into fields as the summer progresses.
Sandhill cranes began showing up in Maine in the early 1990s, establishing a toehold in the Belgrade Lakes area. Nesting was first confirmed in 2000. Their numbers increased slowly at first, but evidence of breeding has accelerated recently, as they’ve begun to spread across Maine.
This may not be the first time sandhill cranes have lived in Maine. The fossil record is unclear. There are six identified populations in North America, and Maine’s subspecies is part of a group that currently breeds in high concentrations near the Great Lakes. While western populations migrate to Texas, eastern cranes winter primarily in Georgia and Florida.
The eastern population was nearly wiped out by overhunting and habitat loss through the late 18th and 19th centuries. By 1930, the entire population numbered just 25 pairs, all nesting in Wisconsin.
Desperate conservation efforts succeeded. Sandhill cranes have been spreading eastward ever since, practically to the Atlantic coastline. Still, they’ve got a long way to go before they fully reclaim their former nesting territories.
A separate population along the Mississippi River also suffers from habitat loss, and continues to decline. Ditto for a non-migratory population in Florida. However, the western subspecies is thriving. Sandhill crane numbers increase every year, despite low reproduction rates. Although they may lay two or three eggs, only one typically survives to maturity.
Every state in the Central Flyway holds a hunting season for sandhill cranes except Nebraska. The Platte River area of Nebraska hosts huge numbers of migrating cranes in early spring. Tourists congregate to witness the natural spectacle.
Perhaps because they are not hunted in eastern states, sandhill cranes on their wintering grounds in Florida can grow quite comfortable around people. Not only do they forage in farm fields, they frequently wander into backyards.
I’m sure the sound of a half-million cranes in migration is deafening. Their calls are among the loudest on the planet. They have nested in recent years on the north end of Pushaw Lake, and I can hear them from nearly two miles away. The noise of a flock can carry for up to three miles.
Sandhill cranes often call in flight. They will catch your attention sounding like a Canada goose blowing through an amplified bugle. Great blue herons are typically silent while flying.
Cranes fly with their necks straight out. Herons fly with their necks coiled in. Cranes stalk around fields. Herons pose motionless, waiting for unwary prey to approach them. They may be similar in stature, but they’re opposites in behavior.
I haven’t yet checked to see if my local pairs returned to Pushaw this year. I presume they have. Sandhill cranes aren’t mature enough to mate until they’re between two and seven years old. When they finally reach maturity, they mate for life and stay together year-round. While you’re reading this, I guess I should paddle across the lake and check — weather conditions permitting.
Maine has strong laws protecting the wetlands cranes prefer for nesting grounds. As their population continues to grow, I expect them to keep showing up and nesting in more places. After nesting, I expect them to wander into nearby fields. They’ll be here all summer.
Nonetheless, despite increasing numbers, sandhill cranes are still unusual in Maine. At the Downeast Spring Birding Festival in Trescott over Memorial Day Weekend, one was discovered foraging in a field just a mile from the headquarters. Despite the fact that dinner was being served, birders jumped into cars and sped out for a look.
