AOn July 22nd, 2020, Clara Pufe found the little animal on the beach in Cadzand-Bad in the Netherlands. Although only the torso and tail were left and the characteristic horse’s head was missing, the six-year-old knew straight away what she was looking for, as she knows seahorses from visits to the aquarium and counts the peculiar fish, which are widely related to perch, among her favorite animals.
Such finds are rare. Not only for young shell collectors, but also for the biologist Rainer Borcherding. He works for the Wadden Sea Conservation Station in Husum and co-developed the website www.beachexplorer.org, on which everyone can share their beach finds, which are then collected in a database. Borcherding has compiled the reports on seahorses from over a hundred years. According to this, just seventy finds have been reported in the North and Baltic Seas since 1886, between which there were sometimes decades without sightings.
Extinct for ninety years
As can be seen from the collection, two of the 43 species of the genus can be found on the Wadden Sea coast Hippocampus before: the long-snouted seahorse (H. guttulatus) and the short-snouted (H. hippocampus). The two are often confused, says Borcherding, but genetic analyzes have shown both species. The habitat of both long-nosed and short-nosed seahorses extends in the North Sea from Belgium up to Denmark and across the Kattegat into the Baltic Sea. “In the Wadden Sea, the short-snouted seahorse predominates,” says the biologist. “I’ve seen that myself.”
The fact that even experts rarely encounter the iconic fish and accordingly little is known about their distribution in the Wadden Sea is due, among other things, to the fact that they are difficult to get at. Where they live, it is too shallow for most research vessels, but they are also difficult to reach for investigations on foot, says Borcherding’s colleague Christian Abel, who is responsible for marine nature conservation at the Lower Saxony Wadden Sea National Park Administration. Seahorses literally live in a transition zone. The fact that they are also rarely washed up on the beaches indicates intrinsically small populations of the animals protected by the Washington Agreement. Seahorses have been considered extinct in the German Wadden Sea since the 1930s.
More data doesn’t automatically mean more seahorses
Are you coming back now? In fact, the watchful Clara find is the latest in a hopeful series to date. Seahorses have been sighted more frequently since 1998, initially in Belgium, but in 2007 several specimens were found in the Dutch and German Wadden Sea. What is particularly striking is what is happening in the Netherlands: there were almost twenty finds in 2019, mostly off Zeeland, and a good thirty by the end of May 2020. Rainer Borcherding also considers this increase to be an observation effect: You can get through the two internet portals beachexplorer. org and waarneming.nl have much better data than before. On the other hand, there was apparently a real wave of seahorses immigrating to the Wadden Sea in 2007.