Studies by WEITNAUER (1980) show that although most Common Swifts die before reaching the age of ten, a large number of the birds checked can be assigned to the age group of 10 – 20 years. This makes the Common Swift remarkable in terms of its lifespan as well. Outside the family Apodidae, such a high age in the wild has so far only been documented in exceptional single individuals of birds of comparable body mass (e.g. many songbirds) (BEZZEL and PRINZINGER, 1990).
WEITNAUER (1980) gives a mean age of 4.7 years for Common Swifts ringed as nestlings; for birds ringed as trapped adults, 3.6 years in the case of birds found dead and 3.2 years in the case of live recaptures after ringing. However, since the birds of the latter two groups were at least one year old when ringed – and at least two years old if they were breeding birds – the mean age they actually reached must be higher than that of the birds ringed as nestlings. As the oldest Common Swifts – ringed as trapped adults – WEITNAUER (1980) names one bird each of 19, 20 and 21 years.
Estimates of the annual mortality of adult Common Swifts (assuming it remains constant) are given, depending on the data and method used, as 15 – 16 % or 20 – 23 % at Oxford / England (PERRINS cited in GLUTZ and BAUER, 1980), and as approx. 19 % at Hasselfors / central Sweden (MAGNUSSON and SVÄRDSON cited in GLUTZ and BAUER, 1980).