RESULTS OF ICHTHYOLOGICAL INVESTIGATIONS IN ZMIINYI ISLAND COASTAL WATERS (2016-2018)

Abstract

The results of ichthyological investigations of Zmiinyi Island coastal waters in 2016-2018 are presented. In total 73 species of fish from 18 orders, 42 families, 59 genera were found.The purpose of this work is to analyze and summarize the results of monitoring studies of ichthyofauna conducted in the coastal waters of Zmiinyi Island in the period from 2016 to 2018Results Ichthyofauna of this region is formed by marine fish species (72.6 % of all species), most of the species are sedentary (69.9 %), bottom and demersal (78.1 %), pelagophiles and species which are protecting eggs (35.6 % and 32.9 %, respectively). About half of the fish species (36 out of 73) have protected status.It was noted that the level of biodiversity of ichthyofauna (Shannon index calculated by abundance) ranged from 0.86-3.27, averaging 2.06 ± 0.71 in 2016, 2.48 ± 0.65 in 2017 and 2.57 ± 0.71 in 2018. Minimum of biodiversity indexes were recorded in November-December. The maximum ones were registered during the warm season (May-October). Catches from July to December 2016 were distinguished by a smaller number of fish species and the dominance of individual mass species, and therefore the biodiversity indicators were slightly lower than the period 2017-2018.In catches, individuals of picked dogfish (average catch per unit effort - 5.02 ± 0.51 - 10.05 ± 0.86 kg, skates (R. clavata) up to 2.86 ± 0.04 kg and (D. pastinaca) up to 8.07 ± 1.19 kg, respectively, whiting - up to 2.61 ± 0.05 kg, scorpion fish - 6.69 ± 0.92 kg, golden grey mullet - 2.65 ± 0.50 kg, round goby – 0. 76 ± 0.07 - 5.31 ± 0.88 kg and turbot - 3.38 ± 1.20 - 6.56 ± 1.24 kg prevailed. The catches of picked dogfish and skates increased in 2017-2018 compared with 2016 and the catches of anchovy, shore rockling, horse mackerel and round goby decreased in the period of investigations.Conclusion The probability of detecting new species of ichthyofauna in the coastal waters of Zmiinyi Island using diving equipment and new non-contact video monitoring technologies remains quite high. Such visual studies will help to clarify the quantitative characteristics of the main fish species in the said Black Sea region.Key-words: ichthyofaunal; catch per unit effort; Zmiinyi Island.