Cities attract birds and other animals particularly in winter because the heat leaking from buildings warms the environment and helps animals to save energy. In addition many bird species find easy ”mouthfuls” on these islands of warmth from food waste left by careless humans but also from food tables meant for birds. The concentration of great tits in cities, already at the autumn migration and particularly abundantly in the winter season, is confirmed by many scientific observations. In northern Finland and Sweden great tits manage to survive the winter only thanks to human activities – the birds gather in communities where they spend the whole long dark winter and only leave from there for the breeding areas when spring arrives.

That tits are the most numerous of bird feeder visitors is also confirmed by the results of the Winter Garden Bird Watch. The tits bustle briskly at the bird feeders in early light, leaving only when dusk falls, and it is almost impossible to make sure who came, who left, to where and whether a bird actually returns to the same bird feeder.

Published in Estonian 17,01.2017

Published in Estonian 29.12.2017

Ecologically species can be divided into specialists and generalists. While the specialissed species are adapted to specific environmental conditions and rapid changes may become difficult for them, then generalists can cope with a variety of conditions – both urban and rural, warm or cold, in forests or open spaces. Thus it is no surprise that that the generalists are often synanthropes, or associated with humans, i e species that have been able to adapt urban life and become numerous, due to their high adaptivity and small selectivity. One of the best known generalists is man himself who can cope in all regions (except the Arctic areas). Few animal species manage to match humans in this.

The great tit that has been staying overnight in the nest box has gathered many viewers via the webcam. Lately it has arrived in the nest box in the evenings between 16.00-17.00 and left by 8.00 at the latest in the mornings. Thus it sleeps more than 15 out of 24 hours during the dark period. How much energy does the tit use during the long winter nights and how much weight does it lose?

The camera image is transmitted by OÜ Teetormaja: www.tt.ee

Only recently the ability of great tits to memorise the location of food hoards of other birds by observing their behaviour was mentioned among the Bird of the Year science news (see note  here). It is known that great tits are better at solving tasks requiring spatial memory than blue tits or marsh tits.

A part of birds fly for winter to remote southern countries while others don’t take the trouble to go on a long journey and when winter arrives remain in place or stray to a smaller extent towards south or north. Such migrating birds which also include the tits that breed here are called roving migrants and they are seen in the literal sense of the word roving around, searching for the best wintering places. True, there are tits that go towards southern areas but in that case too not very far. The reason may be that compared to long-distance migrants the length of the wings of tits, considering body size, became relatively short during evolution since short distances can be travelled also with short wings.

Tits as well as birds of prey gather at birdfeeders and this forces the tits to be constantly on watch. Distinguishing a dangerous bird of prey from a harmless species is vitally important.  While taking to flight  is crucial if a dangerous bird of prey approaches it is not necessary to waste energy in vain  if it is harmless.

From what do the tits recognize the birds of prey that are dangerous to them? The question might seem strange at first but finding an answer has been a real challenge to scientists and because of that until now relatively poorly studied. Evidently it works by way of the birds’ sight but what precisely are the details tonte in the raptor?

Some days ago I observed a nuthatch in the park who was carrying something into a branch crevice. I was not the only one observing this, so also did a great tit. When the nuthatch disappeared out of sight the tit grabbed the booty and went off. This happened several times. Is this behaviour the reason why great tits don’t collect winter stores? Is it simpler to keep one’s eyes open, and memorize the hiding places of others, in order to empty them later?

Many know the various songs of great tits but few have heard the bird hissing like a serpent. Hissing can be heard when you come across a female bird sitting on her eggs in a nest box, elsewhere great tits will not use this call. It is caused by predators such as least weasel, stoat, pine marten, pygmy owl, stray cats that are threats to an adult bird in a tree hollow. Although a nest in a hollow is comparatively well protected from predators the hollow can become a mortal trap if the nest is discovered – the only escape route is controlled by the predator and in the worst case the predator may even be able to get into the hollow.