Bowhead whale aerial abundance survey conducted by Alaska Fisheries Science Center, National Marine Mammal Laboratory from 2011-04-19 to 2011-06-11 (NCEI Accession 0133937)

Aerial photographic surveys for bowhead whales were conducted near Point Barrow, Alaska, from 19 April to 6 June in 2011. Approximately 4,594 photographs containing 6,801 bowhead whale images were obtained (not accounting for resightings). The 2011 field season was very successful: we flew 36 out of 49 available days and conducted 49 flights in that time; we were grounded due to weather on 13 days. The longest period of time that we were grounded due to weather (low ceilings/fog) was three days. This occurred after the migration had slowed down, during a time when few whales passed the ice perches according to the ice-based visual survey. The 2011 migration was steady with several peaks (30 April, 4-5 May, 12 May), and then the migration rate slowed down considerably after 14 May. The photographs taken in 2011 are a significant contribution to the bowhead whale photographic catalogue. They will be used to calculate a population estimate that may be used for comparison with the 2011 ice-based estimate and will provide better precision in estimates of bowhead whale life-history parameters.2011年4月19日至6月6日，研究团队在阿拉斯加巴罗角附近开展了弓头鲸航空摄影调查。本次调查共获取约4594张照片，内含6801张弓头鲸影像（未计入重识别样本）。2011年野外调查季进展顺利：在可开展作业的49天中，实际飞行36天，累计完成49架次飞行；另有13天因天气原因停飞。其中因天气（低云/雾）导致的最长停飞时长为3天，该时段发生在鲸群迁徙放缓之后——根据冰上目视调查结果，此阶段途经冰栖观测点的弓头鲸数量极少。2011年弓头鲸迁徙整体平稳，存在三个迁徙峰值（分别为4月30日、5月4-5日、5月12日），5月14日后迁徙速率显著放缓。本次2011年获取的摄影资料对弓头鲸影像图库具有重要补充价值，将被用于计算种群数量估算值，可与2011年冰上调查得到的种群估算值进行对比，同时能够提升弓头鲸生活史参数估算的精确度。