A small bird with green and yellow body plumage and a glossy black head. In Britain it is familiar in gardens as well as woodland.
White cheeks contrast strongly with its black head and green-and-yellow body.
In spring woodlands, Great Tits and their caterpillar food move through a short seasonal window. Even after a female starts laying, she can alter when full incubation begins and shift the hatch date. Time spent inside the nest is part of matching breeding to the forest’s food season.
A 54-year record from Wytham Woods, near Oxford in the UK, found that synchrony between hatching and the caterpillar peak predicted breeding success better than the dates of clutch initiation or completion. Temperature recordings in 2014 linked the onset of full incubation to mean temperatures around the laying period.
A separate 60-year analysis found that the pace of change in laying dates varied across Wytham Woods and was linked to oak health. The breeding calendar reflects incubation behavior and local seasonal conditions, including the condition of oak trees. Long-term, place-specific records help reveal how these seasonal relationships change.
IUCN Red List (BirdLife International listing) · Least Concern (LC) · Global
BirdLife International’s 2024 global assessment lists the Great Tit as Least Concern (LC) with a stable population trend. In Britain, the BTO/JNCC/RSPB Breeding Bird Survey recorded a 17% decrease from 2014 to 2024, following a long-term increase since the 1960s. BTO recommends continued monitoring and says nest boxes are likely to benefit the species.