Of snails and worms: Where the «Small Five» cavort

Harlesiel
Thousands of species live in the Wadden Sea. Five small inhabitants are particularly important for nature and food chains. With a few tricks, the “Small Five” can be tracked down in the Wadden Sea – sometimes you even learn something about love life in the Wadden Sea.

At first glance, the Wadden Sea looks like an endless, gray mud desert. Life? Rather scarce. But appearances are deceptive. The Wadden Sea is one of the most fertile regions on earth. Only in a few other areas is the biodiversity greater.

More than 10,000 animal and plant species live in the mud flats between Sylt and Borkum. “This incredibly high level of biodiversity is also one of the reasons why Unesco recognized the area as a natural world heritage site,” says Benedikt Wiggering, an expert on biodiversity at the Lower Saxony Wadden Sea National Park Administration.

Many animal and plant species live in the Wadden Sea

Measured against the area of ​​Germany, the beaches, dunes and salt marshes of the Wadden Sea make up just 0.03 percent of the total area – however, according to Wiggering, about a quarter of all plant species known in Germany and a fifth of all animal species are found in the Wadden Sea. There are five residents who, although small, are also particularly important for the Wadden Sea as they serve as food for fish, shellfish and especially birds.

The national park administration lovingly calls them the “Small Five” – ​​in reference to the large animals of Africa known as the “Big Five”: elephant, lion, rhino, buffalo and leopard. This means: shore crab, mud snail, cockle, North Sea shrimp and lugworm.

Discover the «Small Five» on a safari

Similar to the savannah, the “Small Five” can also be discovered on a safari, says Watt guide and national park expert Joke Pouliart from the Wattwanderzentrum Ostfriesland in Harlesiel – namely on a “Watt safari”. Many mudflat guides in Schleswig-Holstein and Lower Saxony offer special mudflat hikes all about the five little creatures.

Expert advice can be helpful, because if you want to discover the sometimes tiny animals, you have to search the mud flats carefully – and sometimes a tool is useful, explains Pouliart. The expert also gives tips on which tracks you can use to find the “Small Five” in the mudflats. Because: “What you have discovered yourself is also anchored much more firmly in your consciousness,” says Pouliart. Not only children, but also adults could learn a lot in this way.

According to the national park administration, the Wadden Sea and the “Small Five” are of global importance, primarily due to the east Atlantic bird migration. Millions of migratory birds rest there on their way from the Arctic breeding grounds to the winter quarters in West Africa. Billions of lugworms, mussels and algae serve as a food source. “The Wadden Sea is a huge buffet for the birds,” says Pouliart. The birds needed the food to fly their long distances of several thousand kilometers.

Mussels, worms, crabs and snails

The “Small Five” are precisely adapted to their environment. The changing tides, the salt water, storms, frost in winter, heat in summer – and also their predators. An overview:

– According to the Wadden Sea Conservation Station, the cockle is probably the most common type of mussel. The empty half fluted shells are often found on the beach. “If you look at the entire cockle from the side, it looks a bit like a heart,” explains Pouliart. The cockle has a digging foot with which it can dig a few centimeters into the mud flats and protect it from predators. But you can still find them by looking for tiny holes on the mud flats. The mussels filter plankton from the water they suck in. “It is said that all the mussels together filtered through the Wadden Sea in its entirety in a week,” says Pouliart.

– The lugworm is probably one of the best-known inhabitants of the mudflats. In order to find him in the mudflats, Pouliart needs a digging fork. Small, brown “spaghetti heaps” of sand on the surface reveal where to look. “The lugworm has to go to the toilet about every 45 minutes,” says the mudflat guide. The worm sits in a U-shaped tube up to 30 centimeters deep in the soil. At one end, it sucks in sand and eats the nutrients it contains. In order to get rid of the indigestible sand, it squeezes it out again at the other end of the tube – it eats up to 25 kilograms of watts a year.

However, the “sand spaghetti” also show birds where to look for lugworms. But the lugworm knows how to defend itself, says Pouliart. If your butt is bitten off during a bowel movement, it will grow back over time. Incidentally, the lugworm can breathe through gills that open up in the water.

– The beach crab is known for its lateral movement, which is why it is also called “Dwarsloper” (cross-runner) in Low German. The crab can crack open shells and snails with its claws. When walking along the beach, empty crab shells are often found on the beach. Because until a beach crab is fully grown, it has to shed its skin many times – the hard shell cannot grow with it. Incidentally, when mating occurs in summer, the males have to wait for the female to molt. “Ms. Krebs has to undress before she gets into the act,” says the guide with a smile.

– The brown shrimp is colloquially often called crab – but unlike the beach crab, it is not a crab with a broad shell, but belongs to the sand shrimp family. It is mainly found in the Wadden Sea during the warm season, in winter the animals migrate to the North Sea. Shrimp fishermen go out to catch them, especially in the fall. For many Watt residents it is also a treat. The brown shrimp is greyish and almost transparent. Only after it is cooked does it turn red.

– According to expert Pouliart, the mudflat snail is probably the fastest snail in the world. However, the tides also help. With the ebb current, the snails glide over the mud flats and thus graze the surface for nutrients. “The snails practically walk on their tongues.” Sometimes their tracks can also be seen on the tideland surface. The mud snails themselves are tiny – they are fully grown at eight millimeters in size.

© dpa-infocom, dpa:220804-99-271304/2 (By Lennart Stock and Birgitta von Gyldenfeldt (text) and Sina Schuldt (photos), dpa)


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