Gravel pits as new wetlands for the little grebe Tachybaptus ruficollis

ENVIRONMENTAL FACTORSGRAVEL PITSLITTLE GREBEMACROPHYTESSOUTHWEST FRANCEABSTRACT.-In southwest France, the increasing abundance of gravel pits has allowedseveral bird species to colonize the region. These wetlands have becomesubstitutes for the natural habitats of waterbirds. Little grebes Tachybaptus ruficollishave colonized southwest France since the availability of gravel pits expandedand began to be exploited by the species in the 1970’s. Little grebe populationswere censused weekly from October 1996 to October 1998 in four gravel pits nearToulouse (SW France). For each period (wintering, post and pre breeding, breeding),we recorded the habitat used by grebes according to environmental variables.Of these, the presence of macrophytes proved to be the most important factor influencingthe little grebe repartition to gravel pits where open water provides securehabitats for this species year-round. This information will be useful for acquisitionand management purposes. Hereafter, in southwest France, conservation efforts forwaterbird communities must consider macrophyte management in unused gravelpits as a viable tool to maintain this species.

F. Santoul, S. Mastrorillo, VIE MILIEU, 2004, 54 (1) : 31-36