Wetland habitat characteristics for waterfowl wintering in Camargue, Southern France : implications for conservation

Abstract

In the Camargue, southern France, 74 wetlands representing more than 90 % of the total wetland surface, support the entire wintering waterfowl populations in the region. We characterized the habitat of these wetlands during the period 1967-68 to 1990-91. We measured five physical variables of the wetlands proper and two variables describing human use. Multiple Correspondence Analysis clearly discriminated freshwater wetlands which are hunted, more productive and highly disturbed, from the protected saline wetlands. A trend was observed during the last 24 years in which a mosaic-type distribution of wetlands has been progressively replaced by a bimodal pattern as a consequence of human interference (water management and disturbance) linked to protection policies and economic (hunting) development. A loss of biological diversity has resulted, requiring new models of conservation. The population size of wintering waterfowl (ducks and coots) did not present corresponding changes, since it seems to result from apparent opposite effects of the described parameters. We recommand better protection of winter habitats for waterfowl populations with less hunting. Wetlands should be managed according to a Mediterranean-type water control including more variability and unpredictability in water levels and salinities.