In 2021, with the support from WWF-Russia, the project "Assessment of the condition of key habitats and development of recommendations to improve protection measures for the stone loach, an endangered endemic of the Kamchatka River" was launched. The work is carried out by Kronotsky Reserve and A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences. At the beginning of the new season the specialists set off to the research sites on a snowmobile.

Stone charr is a large predatory fish that inhabits only the Kamchatka River and its tributaries. Stone charr cannot be confused with any other salmonid: it has a dark coloration with odd-shaped spots. For the last 40 years the stone charr population has been in a constant decline, probably due to the distruction of habitats. In the 21st century, the species has become endangered. Large spawning grounds remain only in the tributaries of the Shchapina River in the Kronotsky Reserve, where there is no logging.

Specialists of the Kronotsky Reserve assume that long ago some of the Northern Dolly Varden trout (malma) species started spawning in small streams surrounded by spruce forests. The bottoms of those streams were littered with fallen needles and, judging from the experiments conducted, the optimal environment for stone charr early development is toxic to the modern malma. Last year, a previously unknown spawning ground was described. This finding confirmed the high degree of isolation of the stone charr from the malma and the hypothesis of its confinement to watercourses of the spruce forest.

Download

This year, the project participants once again set off to the spawning grounds of the stone charr. During the expedition, water and soul samples will be collected for following study of their organic composition. This will allow to trace the dynamics of cheical composition of water at the khnown spawning grounds. Scientists also plan to determine the number of wintering juveniles and assess the food supply available for fish in the wintertime. As a part of the research will be conducted in the upper reaches of the Kamchatka River, the expeditionists were provided with avalanche backpacks and modern means of communication.

"Determination of wintering conditions, the number of juveniles, and the food supply will allow to assess the efficiency of stone charr's reproduction. Probably, it is low in the wild due to snow drift, freezing of streams, and insufficiency of food resources. Should natural reproduction rate be low and food resources be abundant, artificial reproduction directly at spawning grounds could be one of the potential measures of protection of stone charr. There is international experience in sustaining local fish populations that are below carrying capacity of at risk of extinction by supplementing artificially fertilized eggs taken from producers in nearby streams to natural spawning grounds," said Grigory Markevich, senior researcher of the Kronotsky State Nature Reserve.

An encouraging case of such artificial reproduction was performed in 2018 in Kamchatka. With the support from WWF-Russia and the North-Eastern branch of "Glavrybvod" Federal State Budgetary Institution (operates in the field of fisheries and marine resources conservation), students of Kamchatka State Technical University planted 1,500 chum salmon eggs in custom-made in-stream incubators (egg boxes). The incubators were set in a creek near the salmon breeding farm "Paratunsky".

"For that experiment, we used eggs that had reached embryo stage when it was possible to screen eggs to maximize survival rate. In-stream incubators were set in the body of a small brook making the conditions similar to those in the redds. The experiment showed high survival rate of juveniles. Although the technology was not new, it still demanded further testing for each particular species of salmonids. The method could probably be applied to restore the stone charr population," said Sergey Rafanov, the director of WWF-Russia's Kamchatka Ecoregional Office.

As a result of the project, scientists have obtained new information on stone charr's biology, its population structure, distribution of the species. They also mapped areas that require close attention and furhter study.

Along with that, scientists work on other conservation measures for stone charr including:

adding stone charr to the Russian federal list of endangered species;
introducing a complete ban on fishing for stone charr, including recreational fishing;
establishing local protected areas in the spawning grounds in the Kamchatka River.

18+

The stage of field research on stone charr was launched in Kamchatka