Acta Adriatica, Vol. 59 No. 2, 2018.
Original scientific paper
https://doi.org/10.32582/aa.59.2.2.
Reproductive pattern of the anchovy, Engraulis encrasicolus (Linnaeus, 1758), in the Boka Kotorska Bay (Montenegro, southern Adriatic Sea)
Mirko Đurović
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Aleksandar Joksimović
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Ana Pešić
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Olivera Marković
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Slobodan Regner
; Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11 000 Belgrade, Serbia
Milica Mandić
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Zdravko Ikica
; Institute of Marine Biology, University of Montenegro, P.O. Box 69, 85330 Kotor, Montenegro
Abstract
The annual alteration of gonad morphology in anchovy, Engraulis encrasicolus (Linnaeus,1758), caught in the period from July 2006 to June 2007 using beach seines in the region of Boka Kotorska Bay (Montenegro, southern Adriatic) was studied. Samples were taken each month. Total length of individuals ranged from 6.6 to 12.2 cm, while weight ranged from 1.58 to 11.27 g, Their ovaries were extracted and weighed, and a piece of female gonad tissue was sampled for histological analysis. The length–weight relationship of all anchovy specimens was described by the equation: \(W = 0.0032\) \(L_T^3.2537; (r^2 = 0.9528)\). The lowest GSI values were found in November and remained at low levels until April, which corresponded to the gonad rest stage. The GSI increased gradually during April and May, which coincides with the begining of spawning period. Although primary oocytes (stage I) were present during all months, their percentage increased from October and was the highest during the winter months (November-March 100%). Mature cells, stage IV, were present during April – October period, with highest value in May when they comprised 12.3% of total oocyte number. An increase in the percentage of oocytes in the yolk vesicle (II) and yolk (III) stages occurred in April, remaining almost unchanged until October. Smallest average oocyte size was noticed in period November – February with an average of 59.69 μm, while greatest size was recorded in April 2007, 185.84 μm.
Keywords
Engraulis encrasicolus; small pelagic; spawning; oogenesis; length structure; Boka Kotorska Bay
Hrčak ID:
215068
URI
Publication date:
20.12.2018.
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