02149nas a2200193 4500008004100000245012000041210006900161260001200230300001000242490000700252520148200259653000801741653001101749653001301760653001101773653002801784100002001812856012301832 2000 eng d00aOtolith morphology and age and growth of Trachurus mediterraneus (Steindachner) in the Eastern Mediterranean0 aOtolith morphology and age and growth of iTrachurus mediterraneu c2000/// a69-820 v463 aOtolith morphology and age and growth of Mediterranean horse mackerel, Trachurus mediterraneus (Steindachner), in the Eastern Mediterranean (Gulf of Saronikos, Greece) were studied during the years 1989-1992. Length frequency of a total of 4612 specimens was followed by month; ages were determined based upon otolith microstructural interpretations (n = 1611). The otoliths were classified into four types on the basis of differences in the presence, number and appearance of pseudo-annuli in the first year of life. These seasonal rates of formation of pseudo-annuli and the true annuli were examined in samples collected monthly. Successive hyaline rings were interpreted as annuli on the basis of their formation at progressively greater distances from the nucleus, while the opaque rings were not always visible. The time of annulus completion was estimated by the study of monthly marginal increments. This time was found to be around the end of autumn and coincided with the end of the spawning period. The spawning period was identified by following the seasonal changes of gonadosomatic index. Different growth rates of otoliths for each otolith type may have been the result of differences in spawn-date. Mean lengths at age from otolith reading (all types combined) in the monthly samples were applied to the von Bertalanffy equation and growth parameters were estimated: L(inf) = 37.24 cm, k = 0.326, t0 = -0.842. (C) 2000 Elsevier Science B.V. All rights reserved.10aage10agrowth10aotoliths10aPisces10aTrachurus mediterraneus1 aKarlou-Riga, C. uhttps://icgf.myspecies.info/content/otolith-morphology-and-age-and-growth-trachurus-mediterraneus-steindachner-eastern02458nas a2200289 4500008004100000245008700041210006900128260001300197300001000210490000700220520155800227653001101785653001701796653002701813653002101840100001601861700001401877700002001891700001401911700001501925700003201940700001901972700001501991700001402006700002002020856012802040 2003 eng d00aGrowth and reproduction of horse mackerel, Trachurus trachurus (Carangidae)0 aGrowth and reproduction of horse mackerel iTrachurus trachurus i bSpringer a27-610 v133 a

There is a broad knowledge of the growth and reproduction of Trachurus trachurus, although important gaps still exist. Horse mackerel are a long-lived species, reaching up to 40 years of age. They have isometric growth, although the alometric parameter b may vary throughout the year and in relation to latitude. Growth to age 3 is rapid compared to slower growth later in life. Phenomena of density dependent growth have been observed in the northeast Atlantic. Horse mackerel are an asynchronous species. The following stages of atresia have been validated in horse mackerel: alpha, beta, and delta. The transition in females from the spawning state to post spawning is very fast. The spawning fraction in horse mackerel is estimated to be between 8.3% and 20.9%. Horse mackerel have a long spawning season (up to 8 months), which varies according to geography. Length at first 28 maturity is between 16 and 25 cm, most commonly around 21 cm. Males mature at a slightly smaller length than females. The age at first maturity for females has been estimated to range from 2 to 4 years, depending on the geography. Batch fecundity has been estimated to range between 172–209 oocytes per gram-female-weight. Female spawning lasts between 65 and 94 days. An individual female can release from 5 to 16 batches during the spawning period. The estimated potential annual relative fecundity ranges from 1040 to 3280 oocytes per gram-female-weight.

10agrowth10areproduction10aαναπαραγωγή10aανάπτυξη1 aAbaunza, P.1 aGordo, L.1 aKarlou-Riga, C.1 aMurta, A.1 aEltink, A.1 aSantamaría, M., T. García1 aZimmermann, C.1 aHammer, C.1 aLucio, P.1 aIversen, S., A. uhttps://www.researchgate.net/publication/226117829_Growth_and_reproduction_of_horse_mackerel_Trachurus_trachurus_Carangidae03023nas a2200277 4500008004500000020001400045245013800059210006900197260000800266300001200274490000700286520211100293653001702404653001602421653002102437653002502458653004602483653002802529100001602557700001802573700002602591700002002617700001802637700001402655856007602669 2008 Engldsh  a0165-783600aLife history parameters as basis for the initial recognition of stock management units in horse mackerel (Trachurus trachurus)0 aLife history parameters as basis for the initial recognition of  cFeb a167-1800 v893 a

Information on growth, reproductive biology and the distribution of commercial landings was considered in the EU funded project HOMSIR as basis for the initial recognition of management units for horse mackerel. Twenty sampling sites were considered, which covered the entire range of the species distribution. More than 4400 otoliths were aged and the length distributions at age of different sampling sites were compared. Horse mackerel showed great variability in growth although some patterns can be identified. The Mauritanian coast shows the highest median length at age. The increasing trend in median length at age according to the increment in latitude in two different areas (the Portuguese coast and along the west Ireland coast) suggests the possibility of a particular length-dependent migration pattern during the spawning season in these areas. In the Mediterranean, the horse mackerel in the Thyrrenian and the Ionean Seas showed the highest length at age values. The reproductive strategies of the horse mackerel were analysed using the maturity ogives and the batch fecundity. Maturity ogives were estimated in terms of length and age at first maturity. In the Atlantic, both the length and age at first maturity seem to decrease with decreasing latitude. In the Mediterranean, no similar tendency was evident between its western and eastern parts. Statistical differences between all areas were obtained in the analyses of both length (P < 0.0001) and age at first maturity (P < 0.05). Batch fecundity had a decreasing trend with latitude in the Atlantic. In the Mediterranean, data were obtained only from two areas: in Greek waters and off Southern Spain. The individuals from the latter had higher fecundity than those from Greek waters. Statistical differences were found between areas (F = 2.1377; P = 0.0346). The distribution of commercial landings in the northeast Atlantic showed that fish move from the south of Ireland to the Norwegian Sea and northern North Sea to feed in the autumn early winter. (C) 2007 Elsevier B.V. All rights reserved.

10alife history10arecognition10astock management10aαναγνώριση10aδιαχείριση αποθεμάτων10aιστορία ζωής1 aAbaunza, P.1 aGordo, L., S.1 aSantamaria, M., T. G.1 aIversen, S., A.1 aMurta, A., G.1 aGallo, E. uhttps://www.sciencedirect.com/science/article/abs/pii/S0165783607002445