Blackbirds are relatively short-lived birds. They live on average only 3-4 years, but a few reach quite an advanced age.
The oldest known wild individual was 21 years and 1 month. Mortality is high especially during the breeding season - more than half of all deaths occur between March and June.
The population trend for the blackbird shows a sustained period of decline from the 1970s to the mid-1990s, followed by a period of recovery, with a 26 per cent increase recorded by the Breeding Bird Survey between 1995 and 2008.
The recent increase in population has seen the blackbird transferred from the Amber to Green list of Birds of Conservation Concern. Causes for the observed population changes remain unknown, although hedgerow loss and drainage of farmland may have affected blackbirds.
In gardens, blackbird populations have remained stable, and the number of chicks that fledge per nest is higher than in many other habitats. However, food availability is often a problem, and starvation of chicks is a common occurrence, particularly in dry weather.
Gardeners can help blackbirds by avoiding the use of garden chemicals, and by planting shrubs that provide blackbirds with caterpillars, berries, or both.