ENVIRONMENTAL FACTORS AFFECTING GROWTH AND SURVIVAL OF JUVENILE WESTERN ROCK LOBSTERS PANULIRUS-LONGIPES (MILNE-EDWARDS)
ENVIRONMENTAL FACTORS AFFECTING GROWTH AND SURVIVAL OF JUVENILE WESTERN ROCK LOBSTERS PANULIRUS-LONGIPES (MILNE-EDWARDS)
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DOI：
10.1071/mf9750177
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发表时间：
1975-01-01
期刊：
影响因子：
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通讯作者：
CHITTLEBOROUGH, RG
中科院分区：
文献类型：
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作者：
CHITTLEBOROUGH, RG
在控制条件下，测量了温度、光周期、氧气、食物供应、拥挤和肢体自切的影响。生长速率随温度升高而升高，最高可达26℃，超过26℃，生长速率和成活率均下降。不同的光周期长度对生长速率和成活率没有影响，但在持续黑暗条件下，生长速率明显下降。轻度缺氧（60- 67%饱和度）导致脱毛时较小的尺寸增量；饱和度降至47- 55%时，可导致死亡。为了保持最大的生长速度，每天饲喂是必要的。对食物供应减少的第一个反应是换毛频率的减少。更严重的食物短缺也抑制了每毛的生长增量。测量了进料速率和转化率。当幼体被隔离时，换羽的频率（以及生长速度）明显下降。换毛代替失去的两肢时，生长速度不受影响；四肢的替换减少了毛的增加。单次失去多达四个肢体不会导致更早的换毛，但每次蜕皮时或之后立即失去两个或更多的肢体会导致过早的换毛。讨论了这些和其他环境因素（庇护所、盐度、浊度、竞争对手和捕食者）在4年的浅海珊瑚礁生活中对幼鱼的影响。食物供应正在成为决定野生种群生长和生存的主要因素。
The effects of temperature, photoperiod, oxygen, food supply, crowding, and autotomy of limbs have been measured under controlled conditions in aquaria. Growth rate increased with temperature to a maximum 26º C above which both growth rate and survival declined. Varying the length of photoperiod did not affect growth rate or survival, except that the growth rate was depressed significantly in continuous darkness. A mild deficiency of oxygen (60-67 % saturation) resulted in a smaller size increment at a moult; depression to 47-55 % saturation caused deaths at ecdysis. Daily feeding was necessary to maintain maximum rate of growth. The fist response to decreased food supply was a reduction in frequency of moulting. More severe shortage of food also depressed growth increment per moult. Feeding rates and conversion ratios have been measured. Frequency of moulting (and hence growth rate) was depressed markedly when juveniles were held in isolation. At a moult replacing two lost limbs, the growth rate was not affected; replacement of four limbs reduced that moult increment. Single loss of up to four limbs did not result in an earlier moult, but repetitive loss of two or more limbs at or immediately after each ecdysis led to precocious moulting. The impact of these and other components of the environment (shelter, salinity, turbidity, competitors and predators) upon juveniles during the 4 years spent on shallow coastal reefs is discussed. Food supply is emerging as the dominant factor determining growth and survival in the wild population.