Tenth National census of Grey Heron colonies in France in 2014 and comparison with 2007 | Dixième recensement national des colonies de héron cendré ardea cinerea en France en 2014 et comparaison avec celui de 2007
2021
Marion, L.
英语. Tenth National census of Grey Heron colonies in France in 2014 and comparison with 2007. The 10thNational Census of breeding Grey Heron colonies in France occurred in spring 2014 (completed in 2015) thanks to a network of more than 1097 observers belonging to 152 organizations, coordinated by Loïc Marion. The number of breeding pairs reached 29,179 but decreased for the first time by 7.86% compared to 2007, despite a strong increase in the number of colonies (1,677 against 1,274 in 2007 and only 100 in 1974). Except Normandy (+19%), the main decreases in number of breeding pairs concerned the coasts: Picardy (-34%), Aquitaine (-20%), old Brittany (-19%), Nord-Pas-de-Calais (-16.8%), Auvergne (-15.6%), Charentes-Vendee (-14.4%) and Mediterranean coast (-12.2%). The number of breeding pairs of most of the continental areas decreased also, but by only 4-12.7%, except Midi-Pyrenees (+7%) and Tie- de-France (+55.6%). The mean size of colonies fell to only 17.63 breeding pairs, following a decrease observed since 1989 (44.71 breeding pairs), confirming the \"atomisation process\" of colonies (large mother colonies being replaced by numerous small daughter colonies nearer to actual food resources, thanks to the protection of the species making it more tolerant to Man). There were only 4 colonies with more than 200 breeding pairs. The turn-over of colonies was still very high, with 32% of the 2007 colonies abandoned in 2014, replaced by 48% of new colonies on the total of 2014 (63% from 2007). © 2021 Societe d'Etudes Ornithologiques. All rights reserved.
显示更多 [+] 显示较少 [-]National audience
显示更多 [+] 显示较少 [-]