I thought today I would write about my favourite bird – the blue tit. What are they doing now? Well, they would all have finished moulting by now and have a full set of beautiful new feathers. Winter is the best time to watch birds as there are fewer leaves on the trees and the bird’s plumage is at its best. In Britain, where we have our own sub-species called Cyanistes caeruleus obscurus, the females and surviving male juveniles will be on the move. Most of them move about 60 kilometres (37 miles) in a south westerly direction, while the adult males will remain on territory guarding it and the cavity they have chosen to display to a prospective mate in the spring.
The blue tits that move away for the winter will team up with other small birds such as long-tailed tits, great tits, marsh tits, goldcrests and chiffchaffs to form a mixed species foraging flock. These flocks will rampage through the countryside and gardens searching for food and watching out for predators. Many eyes will ensure that any sparrowhawk or other hunter nearby will be spotted. Also, they communicate constantly with each other with many calls including what is called the hawk alarm. This is a high pitched elongated seeee tone which they will all understand means that a hawk or other avian predator is nearby. They will also be telling each other about any food that they find. However, if they stray into a resident male blue tit’s territory, they can expect to be confronted with a tirade of blue tit anger calls and a display of strength and fury.
This will be the status quo until the winter solstice on or about 21st December when things will begin to change. The adult male blue tits will then start to regularly sing and show off to any passing eligible females that venture into his territory. He will occasionally perform the ‘moth flight’ which entails slowly flying down to the nest hole from a high perch while calling and quivering his wings. He will then enter the cavity and pop out again to show the female that he has sole right to it, and it could be hers to build her nest in and lay her eggs during the coming April. Many females will ignore him as they will prefer to move back to the area that they bred in last year, but one will decide he and the cavity are ok and stay with him for as long as it takes to breed.
Dr. Martyn Stenning