The impact of fishing on exploited populations of narrow-clawed crayfish
Abstract
The ratio of males and females in the populations of narrow-clawed crayfish is close to 1: 1. The difference in the sex ratio refects the difference in the ecological and physiological state of males or females in a particular period of capture. The distribution of average daily catches in the studied water bodies of Belarus is different from normal. Ponds with the average daily catch of less than one individual per trap are more common. The differences in the average size of males are statistically significant for the majority of compared populations. Females are characterized by greater stability and smaller variability of size parameters depending on the specific habitat conditions and, more often, statistical differences between the individual females of compared populations cannot be found. However, this stability is relative, since even the average size of females from the same lake (Sominskoye) can statistically significantly differ in different years. There is no statistically reliable dependence of the average size of individuals of the fished part of the population on the intensity of fishing, but the proportion of the fished part of the population (individuals ≥ 10.5 cm) statistically significantly depends on the fishing load, but the significance level of this dependence remains low overall: males – 0,09 and females – 0,06.
About the Authors
A. V. Alekhnovich
Scientific and Practical Center of the National Academy of Sciences of Belarus for Bioresources, Minsk
Belarus
Belarus
D. V. Molotkov
Scientific and Practical Center of the National Academy of Sciences of Belarus for Bioresources, Minsk
Belarus
Belarus
References
1. Алехнович, А. В. Мониторинг популяции широкопалого рака Astacus astacus (L.) в озере Каравайно, Беларусь / А. В. Алехнович, В. М. Байчоров, В. Ф. Кулеш // Вес. БДПУ. Сер. 3. – 2011. № 1. – С.17–25.
2. Ackefors, H. Observations on the Yearly Life Cycle of Astacus astacus in a Small Lake in Sweden / H. Ackefors // Freshwater Crayfish. – 1999. – Vol. 12. – P. 413–429.
3. Faller, M. Annual activity of the noble crayfish (Astacus astacus) in the Orljava River (Croatia) / M. Faller, I. Maguire, G. Klobucar // Bull. Fr. Peche Piscic. –2006. – Vol. 383. – P. 23–40.
4. Цукерзис, Я. М. Билогия широкопалого рака (Astacus astacus L.) / Я. М. Цукерзис. – Вильнюс: Минтис, 1970. – С 280.
5. Рокицкий, П. Ф. Биологическая статистика / П. Ф. Рокицкий. – Минск: Вышэйш. шк., 1973. – 319 с.
6. Штейнфельд, А. Л. Состояние промысла и материала по биологии речных раков Белоруссии / А. Л. Штейнфельд, И. С. Захаренков, Т. Г. Соболь // Гидробиологические и ихтиологические исследования внутренних водоемов Прибалтики: тр. XII науч. конф. по изучению внутренних водоемов Прибалтики, Вильнюс, 22–24 сент. 1965 г. – Вильнюс, 1968. – С. 150–157.
7. Henttonen P. 1993. Moulting, growth, survival and color of crayfish Astacus astacus (L.) juveniles fed diets with and without green plant material and maintained in individual cages and communal tanks / P. Henttonen, J. V. Huner, O. V. Lindqvist, L. Henttonen, J. Pitkaniem // Freshwater Crayfish. – 1993. – Vol. 9. – P. 426–441.
8. Алехнович, А. В. Речные раки Беларуси в современных условиях: распространение, динамика численности, продукционно-промысловый потенциал / А. В. Алехнович. – Минск: Беларус. навука, 2016. – 303 с.
Review
For citations:
Alekhnovich A.V., Molotkov D.V. The impact of fishing on exploited populations of narrow-clawed crayfish. Natural resources. 2019;(1):50-56. (In Russ.)
Views: 188
Email this article 