MANAGING COASTAL GRAZING MARSHES FOR BREEDING WADERS AND OVERWINTERING GEESE - IS THERE A CONFLICT

The winter grazing intensities of brent geese Branta bernicla, pink-fo oted geese Anser brachyrhynchus, and white-fronted geese A. albifrons, and the breeding densities of lapwing Vanellus vanellus, redshank Tri nga tetanus and snipe Gallinago gallinago, were related to the environ mental characteristics of 81 fields within an area of coastal grazing marshes on the north Norfolk coast. Those fields grazed most intensive ly by geese in the winter supported lower densities of breeding waders in the summer than fields that were rarely grazed by geese. Lapwing, redshank and snipe all tended to occur in higher breeding densities on the wettest fields (characterised by large areas of surface water and Juncus spp., high soil moisture content and high water levels infield drains and adjacent ditches) and where vegetation was short (6-14 cm) in late March. The highest grazing intensities of geese were recorded on fields close to the roost sites with brent and grey geese rarely u sing fields at distances of greater than 5 km and 8 km from their resp ective roosts. The two species of grey geese tended to use those field s that were drier and located at greater distances from sources of dis turbance with slightly longer (though still relatively short) swards t han those used by brent geese. In a subset of the fields close to the roost site, brent geese used fields more intensively if they had been heavily grazed by livestock, had a short sward in October and if the s oil was relatively impenetrable. The results suggest that waders, bren t geese and, to a lesser extent, grey geese select areas of grassland with short vegetation, but that the former favour areas where the wate r table is higher than in those areas favoured by geese. It is suggest ed that this potential conflict may be relatively easily resolved eith er by temporal differences in mangement regimes, whereby water levels are raised in spring and summer and lowered in winter, or spatial diff erences in which some fields are managed for geese, preferably those c lose to the roost, and others for waders. Copyright (C) 1996 Elsevier Science Limited