Batch fecundity of Atlantic mackerel, Scomber scombrus L. |
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| Authors: | J J Watson I G Priede P R Witthames † A Owori-Wadunde ‡§ |
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| Institution: | Department of Zoology, University of Aberdeen, Tillydrone Avenue, Aberdeen AB9 2TN, Wales, U.K.;MAFF Fisheries Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 OHT, Wales, U.K.;University College of North Wales, Bangor, Gwynedd LL57 2DG, Wales, U.K. |
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| Abstract: | The total annual fecundity of mackerel, Scomber scombrus L., during a spawning season is produced by release of discrete batches of eggs. Total fecundity is then the product of the number of batches times the batch fecundity ( F bw). An extensive trawl survey of the Western mackerel stock in the NE Atlantic was undertaken in the 1989 spawning season. Batch fecundity was estimated for 298 fish by counting hydrated eggs in ovaries just prior to ovulation. F bw, expressed as eggs g−1 body weight, varied with latitude: south of 51°N, F bw= 55.49, s.e. = 2.04, n = 227; between 51°N and 55°N, F bw= 45.72, s.e. = 3.41, n = 52 and north of 55° N, F bw= 41.33, s.e. = 5.52, n = 19. It is suggested that as spawning fish migrate northwards the batch size decreases with progress of the spawning season. |
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| Keywords: | Scomber scombrus Atlantic mackerel batch fecundity daily egg production method |
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