Tracking changes and shifting homes: within-season displacement of greater flamingos phoenicopterus roseus between mediterranean colonies

Variations in habitat quality in space and time prompt birds to track these changes to optimise their fitness. We investigated movements of Greater Flamingos Phoenicopterus roseus between long-established North Mediterranean breeding colonies and a new, fairly unpredictable, intermittently suitable South Mediterranean breeding colony (Ezzemoul, Algeria). Among the flamingos observed as breeders at Ezzemoul in 2006 and 2009, 59 and 26 ringed individuals, respectively, were observed earlier during the same breeding season at another North Mediterranean colony, thus providing the first evidence of a within-season large scale displacement (> 1000km) from one colony to another. We suggest that breeding failure and a much higher nest density at the northern long-established colonies triggered these movements. Breeding success and body condition of chicks at Ezzemoul compared favourably with those at Fuente de Piedra (Spain) indicating that on a large spatial scale and on a longer time frame, density-dependent breeding success across Greater Flamingo colonies may induce a shift from an Ideal Despotic Distribution to an Ideal Free Distribution.