Field occupancy by breeding lapwings Vanellus vanellus and redshanks Tringa totanus in agricultural wet grasslands

• Published in: Agriculture, Ecosystems & Environment
• Main Authors: Durant, Daphné, Tichit, Muriel, Fritz, Hervé, Kerneis, Eric
• Other Authors: Domaine expérimental de Saint-Laurent-de-la-Prée (ST LAURENT DE LA PREE), Institut National de la Recherche Agronomique (INRA), Sciences pour l'Action et le Développement : Activités, Produits, Territoires (SADAPT), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Ecologie quantitative et évolutive des communautés, Département écologie évolutive LBBE, Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: WET GRASSLAND; SWARD STRUCTURE; GRAZING; BREEDING WADER; BIRD; WATER SURFACE; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; Vanellus vanellus
• Online Access: https://hal.archives-ouvertes.fr/hal-00428082; https://doi.org/10.1016/j.agee.2008.05.013

This study is based on a comparative approach to explore how two breeding waders, the lapwing Vanellus vanellus and the redshank Tringa tetanus, respond to cattle grazing in terms of timing and intensity of grazing in the Marais Poitevin (French Atlantic coast). Generalised linear mixed models (GLMM) showed that the two main predictors determining suitable grasslands were sward structure (i.e. mean sward height and tussock frequency) and water surface. A grazing index (LU.days/ha) was then monitored to tackle the extent to which the occupancy of fields by waders depended upon the grazing management involved in previous autumn, as well as in spring (early and mid-spring grazing). Species’ biology as well as variations in their sward structure requirements may explain why they responded differently to grazing. In the lapwing, a precocious species which nests in short swards (≤ 10 cm) with no/few tussocks, the suitability of grasslands was (at least partly) driven by both delayed (previous autumn) and direct (early spring) effects of grazing. Conversely, the redshank, which nests later and needs taller swards (10-40 cm) did not respond to autumn grazing, but seemed to be more sensitive to mid-spring grazing. Stocking densities (in LU/ha) in spring were also calculated to examine whether, due to potential risks of nest trampling and/or direct disturbance caused by livestock, birds avoided heavily grazed grasslands. Contrary to what was expected, the lapwing and the redshank responded positively to early spring and mid-spring stocking densities, respectively. These results are discussed in the light of the habitat characteristics and the grazing management situation of the study site, as well as their usefulness for the design of agri-environmental schemes.