Great Blue Herons nest building

April 3, 2017 in Nearby Waterbirds

_W7I0289-001Great Blue Herons begin returning to former breeding colonies to breed in February and March. Nest building begins in March or April. Three to five pale, greenish-blue eggs are incubated for 25-29 days by both sexes. Young first fly at around 60 days of age and leave the nest at 65-90 days, at which time they are similar in size to adults. Great Blue Herons have one brood (clutch) per year, however, they may renest if their first clutch fails early in the season.

Great Blue Herons: nest building in Methuen

March 23, 2017 in Nearby Waterbirds

_W7I7304-001Great Blue Herons nest in colonies, often called rookeries or heronries. Heronries are usually in isolated spots away from potential disturbance and near suitable feeding areas.  Herons that are frequently exposed to human disturbance may be more tolerant. Herons nest in deciduous or evergreen trees, usually near the top on vertical branches. Nests are usually constructed in the tallest trees available, on islands, or in trees with water around the base, presumably to reduce the risk of predation by mammals.  Nests are constructed from branches and twigs gathered from the ground, trees, and old nests. Nests are typically 25-40 inches in diameter and 12 or more inches thick. Heronries, like the one near Nevins Farm MSPCA, may be used for decades; however, herons will relocate their colonies in response to increased predation on eggs and young, declines in food availability, human disturbance, and/or death of trees supporting the nests.

Great Blue Heron Rookery – Methuen

April 10, 2014 in Nearby Waterbirds

Perhaps no wading bird in Massachusetts is more familiar than the graceful and statuesque Great Blue Heron. This species has very adaptable feeding habits, readily taking fish, amphibians, crustaceans, reptiles, and sometimes even small mammals. Its broad menu has made it a common sight at ponds, rivers, lakes, streams, marshes, estuaries, coastal bays, and meadows across the state in recent years. That hasn’t always been the case, however. A century ago, breeding Great Blue Herons were all but absent from the Commonwealth of Massachusetts.

Great Blue Herons – Methuen Rookery

April 1, 2014 in Nearby Waterbirds

The Great Blue Herons nests in large colonies with many other mated pairs. These colonies are usually in forested wetlands or on islands with trees. The herons build large nests of twigs high in the trees to discourage predators, such as raccoons and snakes. The nests are often 3 feet across and almost as tall. The colonies are easily recognized by the many groupings of nests scattered throughout the trees.  The Methuen Rookery is busy with courtship activities and nest building!