The coal tit, also known as Periparus Ater, is the very smallest of the European tits. They are approximately 4.5 inches (11.5 cm) in length and have a wing span of 7-8 inches (17-21 cm). They weigh about 8-10 grams. The coal tit is similar to both the willow tit and the marsh tit, and therefore is often confused with these two almost indistinguishable species. In terms of behaviour, the coal tit is very like the blue tit, but does not have the distinctive blue plumage. Their repetitive song, which sounds like ?pee-chew?, is not unlike the song of the great tit, although it tends to be faster.
The under parts of a coal tit are buff-coloured, while the upper parts are a green-grey colour. It has a black crown and bib and bluish-grey legs. The most noticeable differences between the coal tit and the willow and marsh tits are the coal tit?s white nape and striking white wing bars.
Juvenile coal tits can be identified by their brown upper parts and yellowy cheeks, wing bars, nape and under parts.
Coal tits are resident in the UK and tend to be sedentary, often joining woodland flocks in winter that consist of a mixture of tits.
Coal tits enjoy insects as well as a variety of seeds found naturally. They like wild bird seed and will appreciate a supply of sunflower hearts, black sunflower seeds and, during the colder months, suet. They will often be spotted dashing to feeders to grab food before scuttling off to enjoy it in private or to hide it somewhere for later.
Coal tits will hoard food when there is plenty available, hiding it for the future when food is harder to find. However, they do not have the best memory and will frequently forget where this hiding place is. Great tits will rather cleverly watch for coal tits hiding food and retrieve it themselves later!
As with blue tits, coal tits will use empty mouse holes or tree hollows to nest in, lining them with moss for comfort.
Their eggs are white with red-brown spots or speckles. They are small and smooth and have a glossy appearance. The female bird will sit on the eggs until they hatch, and then the chicks will be looked after by both the male and the female, who will take turns to feed them.
Breeding will start around mid-April and there will typically be one to two clutches. Each clutch will be anything from seven to twelve eggs, for which the incubation period is 14-16 days.
In the past, coal tits have suffered as a result of several harsh winters. However, more recent milder weather and the provision of wild bird seed in gardens have led to a slight population increase. There are an estimated 610,000 breeding pairs of coal tits in the UK. They are currently on the green list and, as such, there is no conservational concern about them at this time.