Great Blue Heron

Our largest North American heron, the Great Blue Heron (Ardea herodias), can reach a standing height of about four feet. Its impressive stature makes this species one of the birds most often noticed by the casual observer. Also contributing to its conspicuousness is its frequenting of open habitats such as lakes, ponds, and rivers.

A lanky, long-necked and long-legged bird, this species is mostly bluish gray above, turning to a light pinkish-brown on the neck, with a whitish belly with thin, long dark streaking. In the breeding season the long, spearlike bill is orange or yellow, with the upper mandible turning blackish at other times of year. In flight, the slaty gray flight feathers of the wing can be seen contrasting with the lighter bluish gray feathers of the upperparts. A closer look at a Great Blue reveals small patches of a rich rusty color at each intersection of the body and wings and the body and legs.

This bird’s most common vocalization is a deep, croaking “grownk”– a sound seemingly befitting such a prehistoric, reptilian-looking creature.

The Great Blue usually forages for fish along edges of shallow bodies of water, although it can also be seen hunting in meadows for frogs, voles, or insects. Even birds are sometimes taken if the opportunity comes up; occasional avian prey for this species has included birds even the size of Least Bittern and Eared Grebe.

Most Great Blues leave our area for the winter, though a few linger along unfrozen water throughout the year. The Great Blue Heron’s winter range stretches from the northern United States to northern South America. Migrants begin arriving back in our area in early to mid-March.

Though occasional pairs will nest singly, for the most part breeding occurs in colonies. The nests are bulky, constructed from stick in trees in close proximity to each other, usually in or next to a wetland. The colony clearly visible on Route 121 in Bedford has attracted much attention this year. While it may be tempting to leave the road to approach the remarkable rookery for a closer look, Great Blue Herons are easily disturbed when nesting and could abandon their nests as a result. Binoculars and spotting scopes are a safer way to appreciate and protect our local rookery.