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首页> 外文期刊>ICES Journal of Marine Science >Reproductive biology and abundance of the white-dotted skate, Bathyraja albomaculata, in the Southwest Atlantic
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Reproductive biology and abundance of the white-dotted skate, Bathyraja albomaculata, in the Southwest Atlantic

机译：西南大西洋白点滑冰Bath虫（Bathyraja albomaculata）的生殖生物学和丰富性

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摘要

Size at maturity, sexual dimorphism, gonad development, and abundance of white-dotted skate, Bathyraja albomaculata, were assessed along its geographic range in the Southwest Atlantic, from Uruguay to Tierra del Fuego (Argentina). In all, 291 specimens from eight research cruises conducted between 1998 and 2003 were examined. Length—mass relationships were sexually dimorphic, adult females being significantly heavier than males of the same length. The largest female observed was 762 mm total length (L_T), and 50% maturity (L_(T50)) was attained at 653 mm L_T. The largest male was 732 mm L_T, and male L_(T50) was 628 mm L_T. Female and male L_(T50) were not significantly different and were about 86% of observed maximum size, similar to other Bathyraja species. The lack of sexual dimorphism in size at maturity and the slight difference in maximum size between sexes support the hypothesis of relaxation of selection for large female size in oviparous elasmobranchs. Liver size was not sexually dimorphic. Mature female gonads were symmetrical in terms of mass, and similar in ovarian follicle number and size. Females carried egg cases in April, September, and October, consistent with previous observations around the Islas Malvinas and suggesting year-round egg laying. Bathyraja albomaculata was most abundant on the outer continental shelf and slope between 36°30′S and 45°S (northern area). In contrast, it was generally absent between 48 °S and 52°S (southern area), a region where it was formerly reported as abundant. These differences are coincident with the development of a fishery targeting skates in the southern area, whereas in the north B. albomaculata taken as bycatch are mostly discarded alive.
机译：在西南大西洋从乌拉圭到火地岛（阿根廷）的地理范围内，评估了其成熟度，性二态性，性腺发育和大量白点滑冰，Bathyraja albomaculata。在1998年至2003年之间进行的八次研究航行中，共检查了291个标本。长度-性别关系是两性的，成年女性比相同长度的男性要重得多。观察到的最大雌性为762毫米总长度（L_T），在653毫米L_T时达到50％的成熟度（L_（T50））。最大公头为732 mm L_T，公头L_（T50）为628 mm L_T。雌性和雄性L_（T50）没有显着差异，大约为观察到的最大大小的86％，与其他Bathyraja物种相似。成熟时缺乏大小上的性二态性，并且两性之间的最大大小略有不同，这支持了在卵生性弹性分支中选择较大的雌性选择放宽的假说。肝大小并非两性异形。成熟的雌性腺在质量方面是对称的，在卵巢卵泡的数量和大小方面相似。女性在4月，9月和10月携带卵子，这与之前在马尔维纳斯岛上观察到的情况一致，并建议终年产卵。红毛青虫在外大陆架上最丰富，在36°30′S和45°S之间（北部地区）倾斜。相反，通常在48°S和52°S（南部地区）之间不存在这种情况，以前据报道该地区盛产该地区。这些差异与南部地区针对溜冰鞋的渔业发展相吻合，而在北部，作为副渔获物的B. albomaculata大多被活活丢弃。

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