09-Mar Building for the Future

In woodlands there are a few more birds that decide to take the plunge, most noticeably rooks, crows, wood pigeons, stock doves, pheasants and starlings. When the urge comes to build, starlings accomplish the task quicker than most completing their rag tag affair of straw, grass and feathers in a matter of just a few hours. Other birds that might have started nesting in woods are chaffinches, nuthatches, buzzards and owls. It is the tawny owl and the much rarer long-eared owl that are normally the first to start but our other owls follow quickly.

On more open ground we can expect, but are unlikely, to see the nests of lapwings, skylarks, partridges, woodcocks and stonechats. On or near water there is another select group i.e. herons, cormorants, mallards, moorhens, little and great crested grebes, kingfishers and sand martins. Kingfishers have now returned to rivers and streams from their winter quarters and are likely to be excavating metre long tunnels in river banks. Sometimes they prefer sand banks so artificial ones have been constructed at Barnes Wetland centre to attract them. Sand martins, which also prefer this habitat, sometimes choose to join them. With swans and grebes we can easily watch the whole process of nest building.

Grebes collect small pieces of vegetation together at the edges of ponds and lakes to create a nest about the size of a dinner plate but with mute swans the mound of vegetation can be half a metre high and two metres across. There are few that would attempt to interfere to even get close to a nesting mute swan as we are all told as children the dubious fact that they can break your arms with their wings. Their nests can be seen quite often in London particularly in our larger parks e.g. Hampton Court park.

Other unusual habitats chosen as nesting sites are shingle banks and quarries. Ring plovers are attracted to them now and jackdaws next month. Collared doves prefer hedges, mistle thrushes strong forks in trees and magpies and feral pigeons all manner of different holes. It is also worth checking old abandoned crow and magpie nests as well as squirrel dreys as they are sometimes commandeered by the same birds or possibly owls.

Nests themselves show an astonishing range of different constructions. They can be a metre across in the case of a heron or just a tiny elastic woven ball of lichen, moss and spiders’ webs as is the case in a long-tailed tit’s nest. Magpies have domed nests with entrances at the side whereas lapwings merely use a scrape in the ground. Kingfishers are happy with just a few fish bones to act as their nest. The notoriously untidy nests of crows and magpies are surprisingly durable. The carefully made mud cup of a magpie’s nest has been known to remain in a tree after the rest of the nest has blown away. The positioning of nests is equally varied with crowds preferring the tops of trees whereas thrushes and chaffinches prefer forks in the branches lower down.

Owls, starlings, nuthatches and woodpeckers will all be using any holes available and robins are quite content among the basal roots. We are usually only made aware of all this activity when we see a bird tugging frenetically at possible nest material then flying off with it only to return immediately to collect more. If you become more inquisitive looking at a nest you are likely to suffer a few scolding calls reminding you the nest should remain unseen and undisturbed to avoid it being abandoned.

One of the most enjoyable sights of the month is to watch the commotion of nest building in rookeries. In the first week of March you often see birds attempting to rebuild their nests which, being set so high in trees, have suffered in the winter storms. As this is done there is some argument among birds as to the exact positioning of the nests leading to all manner of scuffles and skirmishes. One of the nesting pair usually stays at the next to stop any pilfering of sticks by neighbours. The other bird collects twigs, grass and even occasionally flowers for its refurbishment. Some rookeries have been in continual use for over a century and in such cases seedlings or even grass has been seen growing in the nests. Below there can be considerable debris of fallen sticks, discarded food, nest lining, eggshells and guano. While the hen is on the nest, the male is highly attentive to her. He feeds her and calls to her more softly than usual. These special calls have been called the rook’s song. He also bows to her a lot and fans his tail. Fortunately for us rooks are unusual in generally letting us get quite close before showing any signs of being disturbed. However, once the alarm is raised half the colony seems to take to the skies with a cacophony of raucous cawing quite different from the croaks and rattles you normally hear within the colony.