The reproductive cycle and life history of the Arctic copepod Calanus glacialis in the White Sea

被引:128
作者
Kosobokova, KN [1 ]
机构
[1] Russian Acad Sci, PP Shirshov Oceanol Inst, Moscow 117218, Russia
基金
俄罗斯基础研究基金会;
关键词
D O I
10.1007/s003000050418
中图分类号
X176 [生物多样性保护];
学科分类号
090705 ;
摘要
Seasonal variations in the gonad development and sex ratio of copepodite stage V (CV) and adults were examined from February to November in order to understand the reproductive cycle and the life history of Calanus glacialis in the White Sea. Gonad maturation, sexual differentiation and moulting to adults take place during the 2nd year of development. Energy accumulation takes place in the spring and summer of the 2nd year. The following autumn/winter is the major period of CV maturation, which occurs independent of food supply. Maturation of males precedes that of females by 2-3 months. The maximum proportions of CV and adult males are found in the population in October and November. The onset of female maturation is observed in February and March, ca. 2 months prior to the spring phytoplankton bloom. Reproduction takes place between April and June. Its termination in the second half of June coincides with the warming of the surface water layer where egg laying takes place. Variations in the gonad morphology throughout the year suggest long life spans and iteroparity of females of C. glacialis in the White Sea. Many of them survive for several months after reproduction and are able to overwinter again. Therefore, females with different life histories co-occur in the population in winter: "young" females recently moulted from the overwintering CVs, and "old" females which have spawned at least once in their life, after which they return to overwintering conditions. In contrast, males have shorter life spans of 3-4 months resulting in a sex ratio skewed toward females at all seasons.
引用
收藏
页码:254 / 263
页数:10
相关论文
共 56 条