Ecology and distribution of the Amur Chebachok  Pseudorasbora parva (Temminck et Schlegel, 1846)  as a biologically invasive species in the delta and estuarine  coast of the river Don

Abstract

Aim. To analyze the results of ichthyological monitoring in order to identify the role of an invasive fish species, Pseudorasbora parva – known in Russia as the Amur Chebachok – in the ichthyological community of the River Don estuary littoral and delta. Material and Methods. Research work was carried out in the prodelta and estuarine watercourses of the Don delta in the period 2007‐2017. To catch the fish, we used bimtral, drag nets, gill nets and other fishing gear. Standard methods were applied to process ichthyological material. A total of 902 specimens of the Amur chebachok were examined. Results. The general characteristics of the invasive species from watercourses of the delta and from Taganrog Bay are given. Its role in the formation of ichthyofauna and its relationship with native species in new habitats has been determined. Dimensionmass indicators and other biological parameters of the species are given. Conclusion. The linear structure of the local population of the Amur chebachok consists of different size groupings corresponding to certain ages. The process of acclimatization of the Amur chebachok in the Don delta is associated with certain interactions with elements of the local biocenosis. It was proved that when there is a high number, both in pond farms and in natural water bodies, the species is an acute food competitor to juveniles of both farmed or local fish. Its rapid spread is due to the high survival rate of offspring, high environmental plasticity, rapid growth, short puberty and the migratory activity of larvae and fry.

Keywords

• amur chebachok
• river don delta
• taganrog bay
• invasions
• native species
• pseudorasbora parva