Seasonal Abundance, Spatial Distribution, Spawning and Growth of Astropecten irregularis (Echinodermata: Asteroidea)
Seasonal Abundance, Spatial Distribution, Spawning and Growth of Astropecten irregularis (Echinodermata: Asteroidea)
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不规则星扇贝（棘皮动物：Asteroidea）的季节丰度、空间分布、产卵和生长
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
R. Seed
中科院分区：
文献类型：
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作者：
S. Freeman;C. Richardson;R. Seed
描述了北威尔士沿海水域的不规则星扇贝数量、空间分布、产卵和生长的季节趋势。不规则海星的种群密度随季节变化，海星的数量分别在夏季和冬季达到最大和最小丰度。其空间分布的变化有力地表明，不规则拟南芥在冬季迁移到近海更深的水域，可能是为了避免强烈的陆上波浪涌动。夏季海星的高密度可能与产卵聚集或有合适的猎物物种有关； 1997年秋季，海星丰度出现了一个较小的峰值，恰逢双壳类 Spisula subtruncata 和 cumacean Diastylis rugosa 的定居，这两种动物很容易被不规则海星捕食。不规则星扇贝在春末夏初产卵，但此后性腺体细胞指数一直保持在较低水平，直到深秋；该指数在整个冬季都在增加，海星在晚春时达到了繁殖高峰。小海星（臂长<24毫米）几乎没有生殖发育的证据。 1996 年 10 月至 11 月期间，不规则曲霉 (<8 mm) 的数量有限，这一小群人在一年内就融入了主要种群。实验室水族箱中海星的运动活动和挖掘深度与海水温度的变化相关；在温度 <8°C 时，活动很大程度上受到抑制，挖掘深度显着增加。海水温度可能是调节沿海水域不规则菌丰度和分布的重要因素。
Seasonal trends in the abundance, spatial distribution, spawning and growth of a population ofAstropecten irregularis inhabiting the coastal waters of North Wales are described. Population densities of A. irregularis varied seasonally with starfish attaining their maximum and minimum abundances in summer and winter respectively. Changes in their spatial distribution strongly suggests that A. irregularis migrates offshore into deeper waters during the winter months probably to avoid strong onshore wave surges. High population densities of starfish which occur during the summer months may be associated with spawning aggregations or the availability of suitable prey species; a smaller peak in starfish abundance occurred during autumn 1997 coinciding with the settlement of the bivalve Spisula subtruncata and the cumaceanDiastylis rugosa , prey species which are readily consumed by A. irregularis. Astropecten irregularis spawned during late spring–early summer, but thereafter the gonad somatic index remained at a low level until late autumn; the index increased throughout winter and starfish attained peak reproductive condition by late spring. Small starfish (arm length <24 mm), showed little evidence of reproductive development. Limited recruitment of A. irregularis (<8 mm) occurred during October–November 1996, and the integration of this small cohort into the main population occurred within one year. Locomotory activity and burrowing depth of starfish maintained in laboratory aquaria correlated with changes in seawater temperature; activity was largely inhibited and burrowing depth significantly increased at temperatures <8 °C. Seawater temperature is probably an important factor regulating the abundance and distribution of A. irregularis in coastal waters.