USE OF THE DRANA LAGOON (EVROS DELTA, GREECE) BY THREATENED COLONIALLY NESTING WATERBIRDS AND ITS POSSIBLE RESTORATION

Six species of waterbirds nested colonially on small Islands in the Dr ana saltwater lagoon in the Evros Delta from 1980 to 1986 and in the f reshwater lake created in 1989, namely avocet Recurvirostra avosetta, collared pratincole Glareola pratincola, common tern Sterna hirundo, l ittle tern Sterna albifrons, gull-billed tern Sterna nilotica and Medi terranean gull Larus melanocephalus. The favoured islands provided gre ater isolation, were larger, and had greater cover of plant species pr eferred by the birds. The most important habitat factor affecting the choice of bird populations in general was isolation of islands. The gr adual concentration of most species in the Drana lagoon was due to hab itat alteration, predation and disturbance in coastal habitats resulti ng in scarcity of suitable breeding habitat. The Drana lagoon had a pr ominent conservation, scientific and economic value and therefore its restoration is recommended by reflooding with sea water, which would b etter ensure the preservation of the values of the area. (C) 1997 Else vier Science Ltd.