Expansion of Maine’s Sandhill Cranes

Early writings containing bird sightings are difficult to interpret due to the fact that the words “crane” and “heron” were often used interchangeably.  Large eggs were described, but it still was unclear as to whether these were from the sandhill crane or some other bird.

Sandhill cranes have been documented in Maine during the breeding season (April-July) since at least 1992.  The first confirmed nesting pair was in 2000.  Since that time, a handful more nesting pairs have been confirmed across the state and even more sightings of adults within ideal nesting habitat during the breeding season have occurred.  They’ve been sighted as far north as Ashland (Aroostook County) and as far south as Kittery (York County).  The bulk of sandhill crane sightings have been in the southwest quarter of the state, with a “hot spot” spanning between Norridgewock and Belgrade. 

The sandhill crane is the world’s most numerous crane with a total population that likely exceeds 600,000 birds.  In North America, there are six subspecies.  Maine’s cranes are members of the greater subspecies (G. c. tabida), which is morphologically the largest, measuring 4.5-5 feet in height, weighing 10-14 pounds, and boasting a wingspan of nearly 6 feet.  For management purposes, the USFWS recognizes six migratory populations in the United States.

The increase in Maine’s crane population is due to the rebound and expansion of the Eastern Population of sandhill cranes, a majority of which breed across the Great Lakes Region and winter in Florida and southern Georgia.  The Eastern Population was nearly extirpated in the 18^th and 19^th centuries; by 1930 only 25 breeding pairs were found in Wisconsin.  Hunting regulations and habitat protection and restoration helped the Eastern Population rebound to over 30,000 individuals by 1996.  Rangewide, the best breeding habitat occurs in Wisconsin and Michigan.  Once these areas and habitats became occupied, the Eastern Population grew and its breeding range expanded in all directions thanks to the availability of wetlands to nest in and agricultural lands that are suitable for foraging.

Adult sandhill cranes are primarily gray in color.  Their most notable field marks include reddish skin on the forehead and crown; whitish chin, cheek and upper throat; and a loud rattling kar-r-r-o-o-o call.  Morphologically, you may think a sandhill crane resembles a great blue heron due to its size and long neck, bill, and legs, but there are a few things that clearly distinguish these two distantly related species.  In flight, cranes hold their necks straight out, whereas herons typically hold their necks coiled in.  Their foraging behaviors differ, too.  Herons typically forage by sitting and waiting for prey to come within striking distance or by slowly stalking prey; whereas cranes will peck at the ground and vegetation and probe the mud as they walk along. 

Sandhill cranes are typically found in open sedge meadows in wetlands that are adjacent to short vegetation in uplands.  As fall migration approaches, they may be seen in flocks in open fields.  Where birds are numerous, these flocks can number into the tens of thousands.  In Maine, where the population is just taking hold, a flock of half a dozen or more is more likely but is still not easy to find. 

Witnessing this large bird at any time of the year - whether it is during its graceful courtship; as a quick flyover; in a fall flock among others; or just heard in the distance – is fresh and exciting for birders and non-birders alike.  Though its population is clearly expanding, sandhill crane sightings in Maine are expected to be a novelty for quite some time.