Cold winter killed off many Little egrets in Ireland

Little Egret during the breeding season: Note the twin plumes at the rear of the head (Photo: Clive Timmons).

September 2010. One of Ireland's most beautiful birds, the Little egret has become quite a familiar sight in many parts of the country, particularly around coastal estuaries and brackish marshes. It is hard to believe that this member of the heron family only began to breed in Ireland as recently as 1996. Throughout much of the 20th Century it was very much a bird of Mediterranean and African wetlands, but it gradually began to expand its range northwards until it became a resident breeder in Ireland and then, a year later, in Britain. It is considered that climate change may very well have played a role in this massive range expansion, allowing this bird to overwinter in areas that were once too cold for it.

Cold winter hit Little egret populations
Last winter was one of the coldest in Ireland for many years, and indeed was the first severe winter since the colonisation of this island by Little egrets. We won't know the full picture until this season's Irish Wetland Bird Survey (I-WeBS) results are in, but it seems that in some areas at least this warmth-loving species was quite badly hit by the prolonged cold spell.

Large flocks on turloughs
It was not all bad news, however, as although Little egrets disappeared from many of their familiar haunts along the south and east coasts, unusually large flocks were discovered during the winter on some of the turlough systems in the west of the country. These seasonal lakes are fed by hidden underground watercourses and so do not freeze as readily as normal lakes. It seems that, although some Little egrets did perish in the harsh weather, many found safe refuge at the turloughs and subsequently returned to their usual heronries to breed.

Little Egret in typical wading posture. (Photo: Clive Timmons)

Little egrets
The Little egret shares the same basic "snake-necked" shape as its more familiar relative the Grey heron, but has snow-white plumage overall, a blackish bill and legs and bright yellow feet. In the breeding season adults grow two long, fine plumes on the back of the head and other lacy plumes on their breasts and backs. Standing 60-65cm tall, they are one-third smaller than the Grey Heron, though are still substantially-sized birds. Like Grey Herons, they nest in trees. Breeding currently appears to be confined to the south and east coasts, but in the winter Little egrets disperse and can be found at wetland sites around the country.

Diet
They feed on fish, amphibians and aquatic insects, and usually wade into water where they can either wait for or dash around after their prey. They also employ a unique hunting technique: they waggle their yellow toes on the surface of water so that they resemble worms, tempting hungry fish to come within striking distance.

BirdWatch Ireland is currently trying to assess the extent of the breeding population of these lovely birds and also to determine just how badly Ireland's Little Egret population was hit by last winter's cold weather. We would love hear from any readers who either came across nesting Little egrets in Ireland this summer or who spot them anywhere during the autumn and winter months when they disperse far more widely. Please email info@birdwatchireland.ie with details of any sightings.

Courtesy of Birdwatch Ireland