Behavioral changes observed in Black Sea anchovy and its possible causes

Date

2018-12-10

Author

Akkuş, Gizem
Gücü, Ali Cemal

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The Black Sea anchovy (Engraulis encrasicolus ponticus) is a migratory species spawning and overwintering at two opposite ends of the Black Sea. It has been reported that the species may display significant alteration in their migration routes and in their spawning grounds. That, in turn, affects the stock and the fishery on this species noticeably. This study focuses on these alterations by comparing the age, length and egg-size distributions of the anchovies sampled within the Turkish Exclusive Economic Zone (EEZ). The results showed that all the variables examined decreases along the longitudinal axis extending from the overwintering areas towards the spawning grounds. This indicated that the youngest anchovies, which are smaller than the old ones and lay smaller eggs, spawns in the areas near to the overwintering ground, and that the part of the population returning to the main spawning grounds (continental shelf of the northwestern Black Sea) were composed of older fish. These results may also indicate that the high fishing pressure on this species could possibly increase the proportion of small size fish in the stock by removing the large individuals and lessening the size of the population returning to the main spawning grounds. And this situation is a very important factor that needs to be considered in fisheries assessment in the Black Sea.

URI

https://hdl.handle.net/11511/74702

Conference Name

Forum on Fisheries Science in the Mediterranean and Black Sea, (10 - 14 Aralık 2018)

Collections

Graduate School of Marine Sciences, Conference / Seminar

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Citation Formats

G. Akkuş and A. C. Gücü, “Behavioral changes observed in Black Sea anchovy and its possible causes,” presented at the Forum on Fisheries Science in the Mediterranean and Black Sea, (10 - 14 Aralık 2018), Italy, Rome, 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/74702.