Longevity summary from 69 years of Estrildidae ringing data in southern Africa

Abstract

This study focuses on the longevity data accumulated for the family Estrildidae, specifically exploring longevity records for each species using ringing data. Longevity is the minimum age reached by an individual as determined by the time elapsed between initial ringing and last recapture or recovery date. In southern Africa bird ringing started in 1948 and is managed by the South African Bird Ringing Scheme. For estrildids, there are 151 831 ringing records. Approximately 7.0% of those ringed individuals have since been resighted, retrapped or recovered. This family is poorly studied and more research is necessary, particularly as certain estrildid species have been highlighted as data-deficient whilst others are potentially of conservation concern. The South African Bird Ringing scheme (SAFRING) has longevity records for 23 of the 27 southern Africa estrildid species. The maximum longevity record was 10.9 years (Blue Waxbill Uraeginthus angolensis). The overall average longevity for an individual is 3.7 years (SD = 2.5). The low longevity values make sense given the low mass (6.3–22.7 g) of estrildids. Coupled with large clutch sizes of four eggs on average, as well as potentially low surivival, estrildids may counter low longevity by breeding at an early age and double-brooding.