Many types of plants and animals live in and around the Oosterschelde. The optimal water temperature, the salt content and the food supply make sure that many birds, fishes and water plants flourish here. Not only are there many different types, but they are also living in large quantities.
There are about sixty-six sorts of fish, which are continually present in the Oosterschelde. Plaice, sole, young flatfishes and flounder are just a small sample. About fifteen types, such as salmon, sturgeon and angler, are rarely seen. The litter of many sorts of fish, such as sole, cod, bass, plaice, dab and herring, grow up in the Oosterschelde. The litter of the following sorts of fish are born in the Oosterschelde: anchovy, sea needles and eel pout.
The Oosterschelde is full of birds. Apart from the West Frisian Islands, this is the area with the most fish. There are four factors which influence the bird population: 1) running water with a high salt calibre; 2) clean, unpolluted water; 3) a quiet, rural environment, and 4) sufficient food. There is an excess of food here. Birds can eat mussels, worms, cockles, shrimps, small fish, sea grass, seaweed and sea lettuce. The favourable circumstances make the Oosterschelde a popular destination for migratory birds. During spring and autumn large groups of birds, ducks and gooses come and go. The most famous are the autumnal migrations towards the warmer areas and the spring migrations towards the breeding ground. The period in which the migration starts differs strongly among the sorts. Larks already return to their breeding places in February, whereas most migration birds do not reach the Netherlands until April, or even May like swifts. In the beginning of August, the swifts, cuckoos and golden orioles leave again, followed by the autumnal migration of many insect-eating songbirds in September. By the time of October, the climax of the autumnal migration is reached.
Mussels and oysters
These shellfish are very important for the fishers in Zeeland. The mussel farmers depend to a great extent on a variety of circumstances that can influence the cultivation. The place where the mussels or oysters grow needs to be chosen carefully. Firstly, the water must run fast enough for a sufficient supply of plankton. Secondly, the water cannot run too fast, because the mussels may then be flooded with sand. Thirdly, long branches of ash wood or oak wood must surround each section. Finally, the mussels need to lie on a harsh, flat bottom during the dilution (settling), surrounded by clean water. Despite the dependency on the quality of the water and the weather influences, the mussel and oyster culture became more professional. The image of old rickety ships has been history for a long time.
The weak parts, also called ‘meat’, are a delicatessen. The mussel season runs from July until early spring. Many mussels are exported to France and Belgium, where one strives to serve the first new mussels. Of course, many mussels are consumed in Zeeland as well. The ultimate mussel town is Yerseke, which almost completely depends on the mussel industry. Mussels contain fewer calories per 100 grams than for instance fish and meat (242 kilojoules – 57 kilocalories). They contain more minerals than meat (100 milligrams calcium, 250 milligrams phosphorus, 6 milligrams iron, 300 milligrams sodium and 300 milligrams potassium) and about the same amount of vitamins (mostly B-complex and 2 milligrams vitamin C). Unfortunately though, many people are oversensitive to mussels.
During the construction of the Oosterschelde barrier, different sorts of stone were used. The fact is that sea anemones, sponges, tunicates, and crumble starfish (Ophiothrix fragilis) each have their own favourite stone. Seaweed also appears in many different types. There are forty-two types of red seaweed, thirty-four types of brown seaweed, thirty types of blue seaweed, and thirty-eight types of green seaweed in the Oosterschelde. Other special creatures, which can be found in relatively large amounts are slugs, Chaetopodes, sea acorns, starfish, jellyfish, crabs and shrimp. Octopuses rarely appear. Although the environment is improving, water sports enthusiasts regularly disturb the animals’ rest.