When to stay and when to go? the determinants and benefits of mate and nestbox retention in an urban population of European Starlings (Sturnus vulgaris)

Abstract

1 online resource (79 pages) : colour graphsIncludes abstracts.Includes bibliographical references (pages 17-20, 38-41, 57-58, 71-73, 78-79).Following the breeding season, individuals must decide if they should they stay with their partner and stay within their territory in the subsequent season. To test why mate and site retention occurs and if retention provides any benefits, a population of European Starlings (Sturnus vulgaris) with over a decade of breeding data (2007 to 2025) was used to examine the frequency of mate and nestbox retention and if condition, and measures of both reproductive success and parental investment were associated with retention. Mate retention frequency was 48.8% and brood condition tended to be higher in broods preceding mate retention. In pairs that bred together for longer periods of time saw no significant benefits from doing so. Nestbox retention frequency was 43.8% and females tended to retain their nestboxes more frequently than males, and nestbox retention was positively correlated with mate retention