Body size constrains the annual apparent survival of lekking Great Snipe Gallinago media males of eastern, lowland population

Abstract

AbstractSurvival of adult individuals is a key demographic parameter, that is critical for conservation programs of species and evolutionary research focused on life-history traits. Here, we present the estimates of the apparent annual survival of lekking male Great Snipes of the lowland population, breeding in wet meadow habitats in the valley of the Pripyat River. We also investigate individual traits such as body size and body condition, that may influence birds’ survival. The annual apparent survival in the studied population was low (Φ (.) = 0.43), but no change in this parameter was found over the period of 22 years. The chances for survival increased with the body size of an individual. We hypothesize that smaller individuals with shorter bills might face limited foraging options compared to larger birds, which may result in insufficient nutrition during challenging life cycle events such as moulting of primaries combined with preparation for long-distance migration conducted in one non-stop flight. Additionally, the presented results indicate that the wet meadow in the Pripyat River Valley provides suitable breeding habitat for this species with sufficient conservation practices held there, and the low annual apparent survival is probably a life-history trait of this species resulting from a “high pace of life” and elevated metabolic rate. To our knowledge, this study provides the first estimates of the long-term population characteristic for the eastern, lowland population of this species, which could prove helpful in the assessment of population viability for this globally declining species.