© Marcel Burkhardt
Rickenbach, O., M.U. Grüebler, M. Schaub, A. Koller, B. Naef-Daenzer & L. Schifferli (2011)
Exclusion of ground predators improves Northern Lapwing Vanellus vanellus chick survival.
Ibis 153: 531–542
Many farmland-breeding wader species have declined across Europe, probably due to reductions in reproductive output caused by high nest losses as a result of agriculture or predation, or low chick survival between hatching and fledging. Most studies have focused on nest failures, and the factors affecting post-hatching survival of chicks are poorly known. In an experimental approach, we fenced parts of the arable foraging areas of Northern Lapwing Vanellus vanellus families to quantify chick survival simultaneously in the presence and absence of ground predators. Lapwing chicks were radio tagged to estimate survival probabilities by daily locations, applying multi state capture – recapture models. During the night, chick survival was considerably lower outside fenced plots than within. During the day, chick survival was higher than at night and did not differ between protected and unprotected plots. This suggests that nocturnal ground predators such as Red Foxes Vulpes vulpes were responsible for a significant proportion of chick mortality. Cumulative survival probability from hatching to fledging was 0.24 in chicks within fenced plots, but virtually zero in chicks outside fenced plots. In farmland, temporary electric fences can be effective in minimizing the impact of ground predators and offer a promising short-term method to increase fledging success of precocial birds.
Keywords: Chick predation, electric fence, Northern Lapwing, multistate mark–recapture analysis, radio tracking, Vanellus vanellus