Grand Harle - Common Merganser

Description:

It is 58–72 cm (23–28 in) long with a 78–97 cm (31–38 in) wingspan, and a weight of 0.9–2.1 kg (2.0–4.6 lb); males average slightly larger than females but with some overlap. Like other species in the genus Mergus, it has a crest of longer head feathers, but these usually lie smoothly rounded behind the head, not normally forming an erect crest. Adult males in breeding plumage are easily distinguished, the body white with a variable salmon-pink tinge, the head black with an iridescent green gloss, the rump and tail grey, and the wings largely white on the inner half, black on the outer half. Females, and males in "eclipse" (non-breeding plumage, July to October) are largely grey, with a reddish-brown head, white chin, and white secondary feathers on the wing. Juveniles (both sexes) are similar to adult females but also show a short black-edged white stripe between the eye and bill. The bill and legs are red to brownish-red, brightest on adult males, dullest on juveniles.

Habitat:

Like the other mergansers, these fish-feeding ducks have serrated edges to their bills to help them grip their prey; they are therefore often known as "sawbills". In addition to fish, they take a wide range of other aquatic prey, such as molluscs, crustaceans, worms, insect larvae, and amphibians; more rarely, small mammals and birds may be taken.[2][3] As in other birds with the character, the salmon-pink tinge shown variably by males is probably diet-related, obtained from the carotenoid pigments present in some crustaceans and fish.[5] When not diving for food, they are usually seen swimming on the water surface, or resting on rocks in midstream or hidden among riverbank vegetation, or (in winter) on the edge of floating ice.[2][3] In most places, the Common Merganser is nearly as much a salt-water as a fresh-water frequenter. In larger streams and rivers, they float down with the stream for a couple of miles, and either fly back again or more commonly fish their way back, diving incessantly the whole way. In smaller streams, they are present in pairs or smaller groups, and they float down, twisting round and round in the rapids, or fishing vigorously in some deep pool near the foot of some waterfall or rapid. When floating leisurely, they position themselves in water similar to ducks. But they swim deep in water like Cormorants too, especially when swimming upstream. They often sit on some rock in the middle of the water, similar to Cormorants, often half-opening their wings to the sun. In order to rise from water, they flap along the surface for many yards. Once they are airborne the flight is strong and rapid.[6] They often fish in as a group forming a semicircle and driving the fish into a shallow, where they are captured easily. Their ordinary voice is a low, harsh croak but during the breeding season they (including the young one) makes a plaintive, soft whistle. Generally, they are wary and one or more birds stay on sentry duty to warn the flock on the approach of danger. And when disturbed, they often disgorge food before moving.[7] Though they move clumsily on land, they resort to running when pressed, assuming a very upright position similar to penguins, and falling and stumbling frequently

Notes:

Overall, the species is not threatened, though illegal persecution by game fishing interests is a problem in some areas.[12] Within western Europe, there has been a marked southward spread from Scandinavia in the breeding range since about 1850, colonising Scotland in 1871, England in 1941, and also a strong increase in the population in the Alps.[4] A small breeding population has recently been established in Ireland. The Goosander is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.