BIVALVIA - MUSCHELN - MUSSELS
									Lebende Große Miesmuschel Living big blue mussel Modiolus modiolus
							Oysters The european oyster can be found on stony grounds on oyster-banks unto a depth of 50 meters. But the populations of the european oysters were shrinking, so that the oyster- cultivators imported oysters from the Pacific-Ocean. That caused the fact, that exotic oysters like the pacific oyster Crassostrea gigas can be found in the North-Sea. In april 2003 I discovered alive single-specimen at wave-breakers or stones. Only 3 years later I found crowds with even big specimen up to 10cm length in the harbour of Neßmersiel. Furthermore I had found specimen up to a length of 7cm, which were settling at pounds of sea-weed together with blue-mussels. The ecological dimension of this invasion is unclear. For the gourmets need synthetic oyster-banks had been constructed and from them the exotic oyster-larvae could spread over the North-Sea. Oysters can change their sex in dependence from the water-temperature. Without special food oysters can survive in an aquarium unto one year; how long they survive if they can get special plancton food is not known.
					Stachelige Herzmuschel Spiny cockle Acanthocardia echinata
										Schnabelmuschel Nut Clam Nuculana pernula