Reduced stocks – increasing interest
Stocks have fallen dramatically, with a 70 percent reduction recorded over the past 30 years, and the species is today on the Norwegian endangered species list. The drastic decline in wild stocks coincided with increased interest in the species among Norwegian consumers. Consequently, during the 1980s interest in farming noble crayfish rose significantly.
The majority of noble crayfish was previously exported overseas, but today Norwegians consume virtually all that is harvested in Norway.
Relatively few “customised” feeds are available that are specifically adapted for freshwater crayfish. Roger Strand, owner of Kasa Krepseoppdrett in Hvaler, wants to test out different types of feed combinations, including the most common today – small shrimps known as Artemia.
As a preliminary project, Nofima scientists Sten Siikavuopio and Harald Mundheim have developed a completely new dry feed, which has been named Nofima noble crayfish feed. This feed was originally developed for king crabs, but has been modified so it is suitable as a start feed for crayfish larvae.
In all, four different dry feed types were used in the trial in addition to the control feed Artemia. The scientists registered the crayfish larvae’s interest in the various feed types, as well as growth and survival rate.
Nofima’s feed and Artemia produced the same result – the best survival rate for the larvae.
“The preliminary results are extremely promising and we recommend continuing with the development of this feed,” the scientists say.
The project is financed as a fellowship through Innovation Norway.