The reserves of individual fish species are gradually getting reduced in the rivers of Armenia, particularly that's true about the brown trout, Kura barbel and the South Caucasus Spirlin living in the upper reaches of the rivers.
'We are currently experiencing problems with the neutralization of individual fish species reserves, as the people didn't virtually assess the risks having occurred during their economic activities, which can have an immediate impact on nature,' Samvel Pipoyan, Dr. in Biological Sciences, Ichthyologist, said during his interview with EcoLur.
The experts outlined those factors, which immediately affect the fish reserves. One of them is electrofishing and fishing with other banned means. 'Fishing with electricity is very common today. As a result, both medium-sized and large fish get eliminated in the river, which are collected by so-called fishermen, while the small fish either are dead or damaged receiving different extents of physical injuries, thus, being incapable of normal existence or reproduction in future.'
Another hazardous factor is the impact of SHPPs. 'Starting from the early stages of SHPP construction, the fish face numerous adversary impacts and obstacles. The environmental flow in SHPP development stage is so little that the river is like a brooklet, where any serious reserves of the fish can't survive. At the same time, the fish passways constructed not in compliance with the biological and physical peculiarities of the fish don't enable the fish flow up or down the river for the purposes of reproduction, wintering and feeding.'
Reservoir construction is another essential hazard for the normal activities of the fish, when the fish may massively get eliminated in the artificial reservoirs or have higher chances of getting infected because of drastic reduction of the water reserves. Particularly, recently the ligula intestinalis, which is a tapeworm of fish, has caused massive infection of cyprinoid fish species.
'Recently there have been causes of massive infection recorded in Aparan, Akhuryan, Kechout, Yerevan reservoirs, where the main infected fish species are the Prussian Carp and the South Caucasus Spirlin. Carps ill with ligulosis are often detected also in Lake Sevan and the rivers flowing into them. Sevan varicorhinus used to be ill with ligulosis, but, luckily, Sevan Trout is not infected with this parasite,' Samvel Pipoyan said.
Photo by Samvel Pipoyan
18:41 November 22, 2017