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  • Dut: Driedoornige stekelbaars (Kraaivis, Paddesteker, Stekebak, Stekeltje, Stekelspoor)
  • Lat: Gasterosteus aculeatus
  • Eng: Three-spined stickleback
  • Ger: Dreistachliger Stichling
  • Dan: Trepigget hundestejle
  • Fr: Epinoche à trois épines
Three-spined stickleback, Ecomare

Three-spined stickleback

Most three-spined sticklebacks spend the winter in coastal waters or river mouths. They migrate in the spring to inland waters where they spawn. Their elaborate courtship has been extensively studied and described. They grow up to 10 centimeters in length and are common in the North Sea, the Wadden Sea and the European rivers. They are small predators, which feed upon young fish, small crustaceans and worms.

  • Stickleback passages on Texel
    The principle of the stickleback passage., Ecomare

    In 1995, the State Forestry had a vacuum passage built for catching three-spined sticklebacks especially for the spoonbills; it is situated in the wadden dike near De Cocksdorp. Two years later, a fish trap was set up for the same purpose between the Moksloot and the Mok Bay. Sticklebacks migrate to fresh water to spawn and thereby form an important source of food for marsh birds. However on Texel, the sticklebacks were unable to reach the fresh water due to impoldering and the Delta Works.
    The passage has been built into the pumping station near De Cocksdorp. Large amounts of sticklebacks are attracted when fresh water is pumped into the sea. The fish is lured to a catching basin with a freshwater current and sucked over the dike with a siphon. The fish is then able to migrate into the polder via the Roggesloot. The siphon is automatically operated from the pumping station.

    During the trial run in early 1996, 40,000 sticklebacks were siphoned over the dike. The number of sticklebacks in the ditches on Texel during this time increased measurably. Three-spined sticklebacks migrate as young fish to sea, but look for fresh water when they become sexually mature. The fish is also capable of staying in freshwater environments, but then it doesn’t grow as large: a freshwater stickleback weighs around 0.6 grams while a migrating cousin will weigh 2.5 grams.
    For the spoonbill, the passage means that food will be available earlier in the year than in the past. Up till 1996, returning spoonbills could not find much to eat on Texel, which delayed nesting by several weeks, in comparison with other nesting colonies.
    The three-spined sticklebacks are not the only ones to profit from the passage. Elver (young eel) also migrate from salt to fresh water, and are therefore enticed by the streaming fresh water. One expects that the eel stock on the island will improve with the opening of the passage.
    The State Forestry did not want to stop with this one installation. There was also talk of a lack of sticklebacks near the breeding colony in the Geul, on the southern end of the island. Therefore, the fish trap was constructed between the Mok Bay and the inland water in the Geul.
    Because the passage uses a lot of water to attract the sticklebacks (350 cubic meters of water per day), it was not used after a year. The water was needed for farming. In addition, wastewater not suitable for the fish also ended up in the passage. The Water Board found a solution. The wastewater is led to a pre-precipitation pond in which water fleas grow. In turn, the water fleas can be used as food for the sticklebacks. The wate is purified via a marsh system and ends up in a deeper pond, where the sticklebacks can grow. Because the wastewater is turned into surface water, it can be used to attract the sticklebacks via the passage. The water fleas are then removed from the shallow pond and brought to the deeper pond, so that the fish can grow well. The spoonbills can profit as well.
    In 2000, a fish passage was also built on Terschelling. So-called flap-divers were built into the sluice, which has led to a strongly increased migration of sticklebacks and eel. The spoonbill is big the winner here.

  • Distribution
    Distribution of three-spined sticklebacks, Ecomare
  • Stickleback groom
    Three-spined stickleback, foto fitis, sytske dijksen