Scientists demand: stone charr be added to the Red Book
The major problem in developing conservation and restoration measures is the extremely low level of knowledge of the stone charr’s biology. These fish are rarely encountered, thus specialists do not know the structure within the species, or the spawning stock biomass. It is important to find new spawning grounds to conserve the fish, study their biology, and plan conservation projects. During the project, supported by WWF-Russia, scientists of the Kronotsky Nature Reserve found new spawning grounds of the Dolly Varden trout’s rare subspecies.
The scientists of the Kronotsky Reserve proved that stone charr’s ancestors started to spawn in the small streams in spruce forests creating a new species. Those areas vary significantly from the other Northern Dolly Varden trout spawning grounds – here, the riverbed is covered with a thick layer of spruce needles which contain large number of resin acids and essential oils. When the concentration of these substances is fairly low, they are healthy. However, at a high level of concentration they poison the fish. Previous researches showed that there were more toxic contaminants at spawning grounds of stone charr than at those of Northern Dolly Varden. A number of experiments proved that such poisonous surroundings were deadly for Northern Dolly Varden trout while the stone charr’s fries survived it very well.
Scientists ascertained that the adaptation to the specific conditions of early development limited the stone charr’s area down to the relict boreal forests of the central part of the Kamchatka peninsula. For the last 40 years, the number of stone charr has been steadily declining. In the 21st century, these species are at the brink of extinction which is probably caused by cutting of old-age spruce forests along river banks. Without spruce trees, the conditions in the streams are changing leaving no place for the stone charr to spawn. The last large spawning grounds remain only in the tributaries of the Schapina River within the boundaries of the Kronotsky Reserve where there was no logging.
Scientists of the Kronotsky Reserve intend to draw more attention to the problem of stone charr conservation. They will seek to add these species to the Russian federal list of endangered species.