Most peo­p­le would pro­ba­b­ly not expect to find any fish at all in Spitsbergen’s rivers and lakes which are fro­zen most of the year. Arc­tic char is quite well known, a fish simi­lar to sal­mon, and pink sal­mon, an inva­si­ve spe­ci­es that has arri­ved in Sval­bard in recent years. Both are main­ly found in lar­ger lakes and lag­gons and rivers that con­nect the­se waters with the sea.

Fish in Spitsbergen’s rivers, arc­tic char and pink sal­mon.

If you do a trip to the east from Lon­gye­ar­by­en in the win­ter, for exam­p­le to Tem­pel­fjord or the east coast, you will pass a litt­le water­fall in Eskerd­a­len, known as Esker­fos­sen. It is a popu­lar place for a litt­le rest.

The water­fall Esker­fos­sen in win­ter.

Curr­ent­ly you can see some­thing pret­ty unu­su­al at Esker­fos­sen: the­re are seve­ral fishes in the most­ly clear ice, just under the sur­face.

Esker­fos­sen with fishes.

It is not just the the view of fishes in the ice of a water­fall is more than just a litt­le unu­su­al. Bey­ond that, it is a spe­ci­es that is so far unknown from Spitsbergen’s waters.

Is it a new spe­ci­es? An inva­si­ve one, or was evo­lu­ti­on incre­di­bly fast this time? Is it con­nec­ted to cli­ma­te chan­ge? The Rus­si­ans? Ali­ens? ..?

Fish in Esker­fos­sen. Image tur­ned 90 degrees for easier vie­w­ing.

The ans­wer to this pro­blem is cer­tain­ly much easier than that: this remar­kab­le dis­co­very was made on April 2, and it is well known which day comes befo­re April 2.

It appears safe to assu­me that, other than Esker­fos­sen, the free­zer in Sval­bard­bu­tik­ken (the super­mar­ket) is most likely the only place whe­re this spe­ci­es can be found in Sval­bard 😄

With this slight­ly delay­ed April fool’s day joke (the ori­gi­nal crea­tor of which is unknown to me) I wish ever­y­bo­dy a hap­py remai­ning April!

View into Tem­pel­fjord from Fred­heim, 12 km north of Esker­fos­sen.