ASIATIC SMELT OSMERUS DENTEX STEINDACHNER ET KNER, 1870 OF THE UDA RIVER (NORTHWESTERN OKHOTSK SEA) — BIOLOGY, ECOLOGY, FISHERY
Data on biology, ecology and fishery of asiatic smelt in the Uda River during its spawning migration are analyzed. The spawning begins in May-June in 2–11 km from the river mouth and lasts 3–10 days. Timing of its start varies from May 22 (2014 and 2018) to June 14 (2001), with 24 days difference. T...
| Published in: | Izvestiya TINRO |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | Russian |
| Published: |
Transactions of the Pacific Research Institute of Fisheries and Oceanography
2019
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| Subjects: | |
| Online Access: | https://doi.org/10.26428/1606-9919-2019-199-83-97 https://doaj.org/article/e4fcc0a7cece447db6cc98a872b8ba98 |
| Summary: | Data on biology, ecology and fishery of asiatic smelt in the Uda River during its spawning migration are analyzed. The spawning begins in May-June in 2–11 km from the river mouth and lasts 3–10 days. Timing of its start varies from May 22 (2014 and 2018) to June 14 (2001), with 24 days difference. The spawning migration begins under the water temperature 6.0 оС, during the spawning the temperature varies from 6.2 to 11.9 оС. The river flow velocity on the spawning grounds is 1.2–2.6 m/s, the river depth varies from 0.3 to 2.5 m. Age of the spawners is 2–8 years, their length is 11.5–32.0 cm and weight 10.8–275.0 g, males usually prevail in number (63–81 %). Depending on the year-class strength, the fish in age of 3 or 4 years prevail among the spawners. After spawning, females leave the spawning grounds immediately — in that time their occurrence in the catches below the spawning grounds can reach 85 %. Size of the spawners decreases during the migration, for males the decreasing was from 19.0 to 15.0 cm in 2007, from 20.2 to 18.8 cm in 2014, from 19.3 to 16.6 cm in 2015, and from 19.4 to 16.0 cm in 2016, for females — from 21.0 to 18.0 cm in 2007, from 22.1 to 19.6 cm in 2014, from 21.3 to 19.0 cm in 2015, and from 24.5 to 16.1 cm in 2016. Annual increments of the smelt body length are 0.7–7.8 cm, on average 3.9 cm, for the body weight 17.1–39.9 g, on average 32.1 g. The minimum registered size of mature male and female was 11.5 and 13.0 cm, respectively. Percentage of the smelt with non-commercial size during spawning migration was 19.2 % in 2007, 0.4 % in 2014, 15.4 % in 2015, and 28.4 % in 2016. The group linear growth of asiatic smelt could be approximated by Bertalanffy equation: L = 30.5 [1 – e–0.317 (t – 0.533)]. Its body length dependence on weight is described by the equation of simple allometry: W = 0.002 L3.380 (determination r 2 = 0.92–0.99). The body weight depends on age as the function: Wt = 2.974t 2.136. Individual absolute fecundity of the smelt in the Uda varies from 11300 to 141300 eggs, on ... |
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