Data from: Genetic variation in blue whales in the eastern Pacific: implication for taxonomy and use of common wintering grounds

Many aspects of blue whale biology are poorly understood. Some of the gaps in our knowledge, such as those regarding their basic taxonomy and seasonal movements, directly affect our ability to monitor and manage blue whale populations. As a step towards filling in some of these gaps, microsatellite and mtDNA sequence analyses were conducted on blue whale samples from the Southern Hemisphere, the eastern tropical Pacific (ETP), and the northeast Pacific. The results indicate that the ETP is differentially used by blue whales from the northern and southern eastern Pacific, with the former showing stronger affinity to the region off Central America known as the Costa Rican Dome, and the latter favoring the waters of Peru and Ecuador. Although the pattern of genetic variation throughout the Southern Hemisphere is compatible with the recently proposed subspecies status of Chilean blue whales, some discrepancies remain between catch lengths and lengths from aerial photography, and not all blue whales in Chilean waters can be assumed to be of this type. Also, the range of the proposed Chilean subspecies, which extends to the Galapagos region of the ETP, at least seasonally, perhaps should include the Costa Rican Dome and the eastern North Pacific as well.蓝鲸生物学的诸多领域迄今仍未得到充分研究。我们在相关领域尚存诸多认知空白——例如其基础分类学与季节性移动模式，这些空白直接制约了蓝鲸种群监测与管理工作的推进。为填补部分此类认知缺口，研究人员针对采自南半球、东热带太平洋（eastern tropical Pacific, ETP）以及东北太平洋的蓝鲸样本，开展了微卫星（microsatellite）与线粒体DNA（mtDNA）序列分析。分析结果表明，东热带太平洋的栖息群体存在分化：来自东北太平洋的蓝鲸对中美洲外海被称为哥斯达黎加穹地（Costa Rican Dome）的海域表现出更强的栖息偏好，而东南太平洋的蓝鲸则更青睐秘鲁与厄瓜多尔周边水域。尽管南半球整体的遗传变异模式与近期提出的智利蓝鲸亚种分类地位相符，但在捕捞体长与航空摄影测量体长之间仍存在部分差异，且不能认定智利海域内的所有蓝鲸均属于该亚种。此外，提议中的智利亚种的分布范围至少在季节层面可延伸至东热带太平洋的加拉帕戈斯海域，该范围或许还应涵盖哥斯达黎加穹地与东北太平洋东部海域。