Due to the early timing of the spring flood of 2026, the warming of the rapidly entering vast spawning grounds of the water masses was much slower, including due to negative weather anomalies. Unfortunately, with a favorable level regime, so far more favorable temperature conditions exist only for early spawning fish species: pike, perch, walleye, asp and silver crucian. The temperature of the water entering the delta on May 8 did not reach even 7 ° C, warming up in areas in the shallow coastal waters of spawning grounds was up to 5-6 degrees higher as usual.
Spawning of pike and perch in the delta and avandelt of the Volga River this year began at the end of the first and beginning of the second decade of March and is currently continuing due to low temperatures. At the end of April, producers of walleye and asp adhered to spawning areas in the coasts of the bayous and yerikov, near thickets of coastal shrubs flooded with hollow waters. The most environmentally plastic species, the silver crucian, has been spawning since the end of March, choosing shallow and better-warmed areas of spawning grounds for spawning. To some extent, such areas were developed by producers of gouster, and, occasionally, rudd and carp.
Visits in the first decade of May to the spawning grounds of the Volga delta and the lower part of the Volga-Akhtuba floodplain estimated the widespread flooding of spawning grounds up to 80% of the maximum area. However, at low water temperatures, a significant number of fish clutches were dead, affected by saprolegnia. When studying the emerging food supply, it was noted the poor species diversity and low quantitative characteristics of forage zooplankton. In early May, at a shallow depth in the coastal areas of spawning areas, the first few schools of larvae of cyprinid fish were observed.
The prevailing hydrological and temperature conditions indicate a strong shift in the spawning time of many phytophilic fish species, which, given the expected onset of water decline, may negatively affect the overall spawning efficiency of fish producers and contribute to low yields of juvenile fish this year.
During monitoring carried out by other laboratories of the branch, catches in fishing areas in the Volga Delta watercourses, where fishing is carried out by river seines, in early April, up to 80% of the Main Bank was bream, carp were present in catches, young individuals of Russian sturgeon and sterlet were noted from passing fish species, on Baltsuga and Grannoy Fish from the families of carp, perch, and catfish were noted in non-aquatic catches, the basis of the catches were bream, silver crucian carp, and asp, young individuals of Russian sturgeon and sterlet of different ages were occasionally found. In early May, fish catches at the fishing grounds decreased significantly. Monitoring observations in the Volga River avandelt showed that by May, bream dominated in the coastal fishing zone by up to 60%, pike (3-8%) and silver crucian (8%) were found in small numbers, carp, rudd, gaster, walleye, perch and catfish were also observed.
Monitoring of migrations of aquatic biological resources and the natural reproduction of fish under existing water management and hydrometeorological conditions will continue throughout the summer. The preliminary results of natural reproduction will traditionally be presented in November.
VNIRO Press Service