Great Blue Herons are more social this time of year
By Betsy Kane
For the Washington Daily News
Everyone is pretty familiar with the Great Blue Herons in the ponds around the city boardwalk in Washington. You can almost always see at least one or two “GBH” patiently stalking prey in these ponds, whether the target is a pan-sized bluegill, a herring larger than the heron’s head and beak, a frog, a small turtle, or a crawfish.
A reader asked last week if I could explain why one great blue heron that frequents the turtle pond appears larger and shaggier than the other. I had to research this question. Turns out that male Great Blues are larger than females. After maturing for a couple of years, Great Blues both female and male also develop “aigrettes” which are rough, shaggy feathers that adorn their neck and sides in breeding season. This term is where the word “egret” comes from, or vice versa.
Great Blue Herons of both sexes are normally territorial and solitary. In breeding season, they change their usual pattern of isolation and aggression towards other GBHs. The shaggy aigrettes, along with ritual display movements, are a visual signal of this change so that pair-bonding and joint nest-building and nest-guarding activities can occur between these normally solitary hunters. The ritual displays between members of a bonded pair can include greeting movements of the head and wings, transferring a twig, and bill-clapping as one bird spells the other at the nest.
Here in North Carolina the breeding season of the Great Blue Heron can occur from about November until April. So, it seems that late winter is prime time to observe the shaggy feathers and nesting activities. The nest is often quite distant from the heron’s daytime feeding areas. Nests tend to be constructed on low islands full of dead trees and shrubs (rookeries where multiple herons nest) or in isolated swamps. A watery surrounding allows for protection from potential nest predators such as raccoons and foxes.
Now for an update on some other birds. Seasonal sightings last week include Baltimore Orioles at feeders around Washington; a Blue-Headed Vireo in Goose Creek State Park; American Pipits in fallow fields west of Washington; a flotilla of Ruddy Ducks in Bath Creek; and, from the Bayview-Aurora ferry crossing, Lesser Scaup, Mallard, Ring-necked Ducks, and Red-breasted Mergansers.
Betsy Kane is a Washington resident who enjoys the outdoors.