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...because it broods under the windowsill of the M&P office in Hanover.
Our colleague Till Gorgs managed to capture them on a little video.
The inquisitive titmice are cavity-nesting birds that, in addition to their original tree and woodpecker cavities, mainly use nest boxes on trees for breeding. Occasionally they also look for nesting opportunities in wall cracks, under roof tiles, under flat roofs or in other cavities on buildings - sometimes even in letterboxes or watering cans!
Blue tits usually breed only once a year, but have very large clutches of up to 14 eggs and a correspondingly high food requirement for the hungry brood. They fledge after about 2 weeks, but are still dependent on feeding by their parents for a long time.
The blue tit (Cyanistes caeruleus) reaches a size of twelve centimetres and a weight of ten grams. It is thus just half the size of a sparrow. Despite their modest size, blue tits are very self-confident birds. They loudly assert their feeding places against other bird species and often even chase them away. If they have not already been killed as youngsters by larger birds or voracious mammals such as the marten, blue tits can live up to five years.
More information about the blue tit can also be found on the pages of the Nature and Biodiversity Conservation Union (NABU): https://www.nabu.de/tiere-und-pflanzen/voegel/portraets/blaumeise/
It's nice that animals also feel at home with us 🙂