Our Birds of New Brunswick: An Annotated List says that the Little Blue Heron (Egretta caerulea) is a rare spring through fall visitor. You wouldn't think so this year! We have had 2 immature individuals at the Sackville Waterfowl Park and Tantramar Wetlands for about 3 weeks now. And recently (August 28) a report came in of another immature Little Blue Heron at Pleasantville, Nova Scotia. Many people have had the privilege of seeing the ones in Sackville.
As its name implies, the Little Blue Heron is a small heron compared to the Great Blue Heron. It is 61 cm (24 inches) long compared to the Great Blue Heron which is 117 cm (46 inches) long. The adults are dark blue-gray with a brownish-purple head and a dark beak. The immature bird is strikingly different. Note the photos above. The Immature is all white occasionally with dark tips to the primary feathers. Notice, the bird shown above is all white. The adult plumage is acquired during the second summer, showing a mixture of white and blue. See the photo below. The bill is a dark gray at the tip and lighter towards the head. The feet and legs are a dark yellow.
The breeding adult shows plumes and a crest which it raises occasionally. The plumes of this species are lanceolate and not filamentous. The lack of such showy plumes saved this species in the past from heavy human predation due to the millinery industry.
The adult Little Blue Heron could be confused with the Reddish Egret but the egret is larger, has shaggy plumes on its head and its bill is pink-based and black-tipped. The immature Little Blue Heron needs the most care in identification. The most likely species you might confuse it with is the Snowy Egret. They are both white and of similar size but the Little Blue Heron has a stouter bill and yellowish legs and feet. Note the adult Snowy Egret had black legs and yellow feet. The feeding posture of the Little Blue Heron is characteristic. It searches for food with its neck bent at a 45ª angle to the water. Some might confuse the Little Blue Heron with a Tricolored Heron but the Tricolored has dark upperparts and white underparts.
The Little Blue Heron feeds in fresh or salt water but it prefers fresh water swamps and lagoons. It walks along slowly or stands still with its neck bent feeding on fish, invertebrates, amphibians, crustaceans and the odd turtle or snake. This species is found mainly along the Atlantic coast from Massachusetts to Florida particularly in the Gulf of Mexico. It is also found in the West Indies and Mexico south to Peru and Uruguay in South America.
A colonial nester, it breeds on the edge of other heron colonies. The nest is flimsy, made of sticks and is usually 1 to 5 metres (3-15 ft) above the ground or water. Both adults help incubate the 1 to 6 pale blue-green eggs for 22 to 24 days. The young do not leave the nest until they are 6 to 7 weeks old.
An interesting fact about this species is that the Snowy Egret tolerates the immature Little Blue Herons feeding near them more than they do the adults and the immatures catch more fish when they are near the Snowy Egrets. It is interesting to learn how well birds have adopted feeding advantages.
Post-breeding dispersal occurs with this species, often as far north as Maine and our area. I doubt if we will ever have a 'battery' of Little Blue Herons but it appears that each year we will be graced with a few in spring and fall.
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