Kingfisher

Autor: Magdalena Zadrąg    

Not all European birds are brownish-grey and are inconspicuous, camouflage well and have unnoticeable plumage. That can be seen easily by walking along the Vistula. In many places, even very close to the Warsaw centre you can come across an incredibly blue kingfisher.

It is a small bird, weighing about 36-50 grams with a wingspan of 26-28 cm.
The top of its body is intensely blue, especially in adult males it may even shine, the plumage of young birds and females is a little less bright. The abdomen of the bird is a bit rusty in colour, and its bill is black in males, and black with red mandible base in females. If we have the chance to look at it closely, we can see that adult birds also have bright red legs, and the young have grey ones. The voice of the kingfisher is also distinctive – sharp, quickly repeated extended “tije”, often reminiscent of a shrill whistle.

Incredible plumage colours. Photo Paweł Wacławik

Incredible plumage colours. Photo Paweł Wacławik

Reach and population numbers
Kingfishers occur almost in all of Europe, in northern Africa, and also in Asia – beyond the far north in Indonesia and the Himalayas. In Poland the kingfisher is not a very pnumerous nesting bird, its population is estimated at 2,500-6,000 pairs and it is one of the largest populations in Europe. Numbers of kingfishers can decrease markedly after very cold winters, because these birds do not migrate over long distances, often in fact they remain in their areas for the winter, and then long frosts, when the water freezes over, prevent them from finding food.
Kingfishers require suitable habitats, they live by clean inland waters, especially by streams, rivers, banks of lakes and ponds. The water has to be clean, so that it is possible to see fish and insect larvae in it. In addition, there have to be observational points in the area from which the bird will be able to prey, for example branches hanging over the water surface, or roots protruding from the banks. There have to be sandy or clay banks nearby, in which the bird could make nests.

The kingfisher. Photo Marcin Łukawski

The kingfisher. Photo Marcin Łukawski

Breeding
The kingfisher makes nests in earth burrows, which it digs in spring in escarpments by rivers and lakes. Entrance to the burrow is usually about half a metre from the water and sometimes higher. Such location of nests means that virtually no predator is able to access them, although if the nest is too close to the surface, it can be dug up, for example by a fox. The burrow is usually 8 cm. in width. Adult birds usually find areas near the nest where they can rest between successive feeding of the chicks. The burrow has a tunnel about 60-70 cm in length, at the end of which is the breeding chamber, where the female lays 6-7 eggs. The eggs are completely white and round. The female and male take turns to incubate the eggs, and the incubation process takes 19-21 days. Completely bald and blind chicks hatch from them, which are typical nestlings, as they remain in the nest for about 4 weeks.

Steep river bank - the kingfisher’s nesting place. Photo Ewa Kominek

Steep river bank – the kingfisher’s nesting place. Photo Ewa Kominek

Food
Adult kingfishers eat mainly small fish 7-8 cm in length, they prey by searching for their victims from the lookout, which most often is a branch, a root or something similar found above the water surface. The bird sits on the lookout and searches for the victim in the water, when it notices one it throws itself into the water and quickly catches it with its bill. Then it emerges from the water and again sits on its branch with the victim in its bill. Then it deafens it by hitting its head on a branch and swallows it. The kingfisher swallows the fish whole, always with the head to the front in order to avoid catching on sharp fins, particularly the spinal fins, in its esophagus and stomach. The bird cannot digest scales and parts of fish bone, but does not get rid of them before swallowing the victim. After digesting the meal it gets rid of them by creating a so-called spit-out. Research shows that about 55% of kingfishers’ victims are young roach and bleak. These birds also prey on sun bitterns, ciril buntings, and also on young pike and perch.
The parents also bring the chicks in the nest small fish, at first 1-2 cm in length, and also small insect larvae, such as dragonflies and caddisflies.

Threats
The main threat to kingfishers is pollution, mainly of rivers, which affects the clarity of water, as well as organisms living in it. In addition, harmful substances in consumed fish may accumulate in the bodies of birds. Besides damaging the regulation of watercourses, the concreting of riverbanks and water reservoirs prevents them from setting up nests. The problem may also be the too zealous removal of branches and roots from the banks of ponds and lakes by administrators, which means that in turn these birds are unable to prey.

Literature:
Chylarecki P., Sikora A., Cenian Z., (red.): Monitoring ptaków lęgowych . Poradnik metodyczny dotyczący gatunków chronionych Dyrektywą Ptasią. Warszawa, GIOŚ, 2009.
Kruszewicz A.: Ptaki Polski Tom I., Warszawa, Wydawnictwo Multico, 2005.
Reynolds S.J., Hinge M.D.C.: Foods brought to the nest by breeding Kingfishers Alcedo atthis in the New Forest of southern England.Bird Study, 43:1,96-102, 1996.
Tomiałojć L., Stawarczyk T.: Awifauna Polski. Rozmieszczenie, liczebność i zmiany. Wrocław. Wyd. PTPP „pro Natura”, 2003.

The project ‘Protecting the habitats of priority bird species of the Vistula Valley under conditions of intensive pressure of the Warsaw agglomeration’ (wislawarszawska.pl) has received a grant from the Financial Instrument for the Environment (LIFE+) and from the National Fund for Environmental Protection and Water Management.