Before and after wasting disease in common eelgrass Zostera marina along the French Atlantic coasts: a general overview and first accurate mapping
|Author(s)||Godet L1, Fournier Jonathan1, Van Katwijk M2, Olivier F1, Le Mao Patrick3, Retiere C1|
|Affiliation(s)||1 : Museum Natl Hist Nat, Dept Milieux & Peuplements Aquat, Stn Marine Dinard, USM0404,UMR 5178,BOME 17, F-35800 Dinard, France.
2 : Radboud Univ Nijmegen, Dept Environm Sci, NL-6500 GL Nijmegen, Netherlands.
3 : IFREMER, Lab Environm & Ressources Finistere Bretagne Nord, Stn St Malo, F-35402 St Malo, France.
|Source||Diseases of aquatic organisms (0177-5103) (Inter-Research), 2008-05 , Vol. 79 , N. 3 , P. 249-255|
|WOS© Times Cited||27|
|Keyword(s)||France, Accurate mapping, Long term change, Wasting disease, Common eelgrass, Zostera marina|
|Abstract||We examined the original manuscripts of a French national survey conducted in 1933 on the state of common eelgrass Zostera marina beds along the French Atlantic coasts during the period when wasting disease struck the entire North Atlantic population in the 1930s. Based on GIS related techniques and old sets of aerial photographs, we present the first accurate mapping of the Z. marina beds before wasting disease occurred and assess their spatial recolonization since the 1950s in the Chausey Archipelago (France), which contains large Z. marina beds. The national survey confirmed that the Z. marina beds almost totally disappeared from the French coasts during the 1930s. However, the disease symptoms seem to have begun locally a few years before. On the study site, we found that the Z. marina beds were more than twice as extended than as they are today, and covered both subtidal and intertidal areas. By the 1950s, 20 yr after the onset of the disease, the beds had hardly recolonized, and contrary to the recolonization patterns reported elsewhere in Europe, they were mainly restricted to subtidal areas. The subtidal and intertidal Z. marina beds on the site are now rapidly expanding.|