Antarctic Pack Ice Seals: Immunogenetic Diversity of Antarctic Pack Ice Seals

南极洲周围的浮冰地区至少拥有世界海豹数量的50%，约占世界鳍足总生物量的80%。作为一个群体，这些海豹是南大洋生态系统中最主要的顶级捕食者之一，它们的丰度、生长模式、生活史和行为的波动提供了一个潜在的信息来源，可以在广泛的空间和时间尺度上综合环境变异性。这项建议是作为国际南极包冰海豹(APIs)计划的一部分制定的，该计划旨在更好地了解包冰海豹的分布与其环境之间的生态关系。在2000年1月至2月期间，将进行一次穿越罗斯海东部和阿蒙森海西部浮冰地带的研究巡航，沿垂直于大陆架的六个横断面进行调查和采样。每条断面都将通过五个环境采样层：大陆架带、南极斜坡前缘、远洋带、冰缘前缘和浮冰带外的开阔水域。除开阔水域外，所有区域都将在一定程度上被冰覆盖。API计划的这一组成部分将侧重于两组遗传基因座的变异，以确定浮冰海豹在整个物种范围内的遗传变异性。一组是与免疫系统反应有关的主要组织相容性复合体，另一组是不编码基因产物的微卫星位点。双重方法将使研究小组能够评估和量化具有整体遗传变异背景的物种中与免疫相关的遗传变异的数量。这项研究将补充有关南极冰海豹健康状况的其他研究。更好地了解群冰海豹与南极海洋生态系统的生物和物理特征之间的相互作用，将有助于更好地预测在环境变化背景下海豹种群的波动。

9816011STEWARTThe pack ice region surrounding Antarctica contains at least fifty percent of the world's population of seals, comprising about eighty percent of the world's total pinniped biomass. As a group, these seals are among the dominant top predators in Southern Ocean ecosystems, and the fluctuation in their abundance, growth patterns, life histories, and behavior provide a potential source of information about environmental variability integrated over a wide range of spatial and temporal scales. This proposal was developed as part of the international Antarctic Pack Ice Seals (APIS) program, which is aimed to better understand the ecological relationships between the distribution of pack ice seals and their environment. During January-February, 2000, a research cruise through the pack ice zone of the eastern Ross Sea and western Amundsen Sea will be conducted to survey and sample along six transects perpendicular to the continental shelf. Each of these transects will pass through five environmental sampling strata: continental shelf zone, Antarctic slope front, pelagic zone, the ice edge front, and the open water outside the pack ice zone. All zones but open water will be ice-covered to some degree. This component of the APIS program will focus on the variation of two sets of genetic loci to determine species-wide genetic variability of pack-ice seals. One set is the major histocompatibility complex, which is involved in immune system responses while the other is the microsatellite locus which does not code for a gene product. The dual approach will enable the team to assess quantify the amount of immunologically-relevant genetic variation in a species with the background of overall genetic variation. This study will complement others on the health status of Antarctic ice seals. Better insight into the interplay among pack ice seals and biological and physical features of Antarctic marine ecosystems will allow for a better prediction of fluctuation in seal population in the context of environmental change.