Killer whales occurrences in Venezuelan waters 1982-2008

Original provider: Jaime Bolaños-Jiménez Dataset credits: Jaime Bolaños-Jiménez Abstract: Reported occurrences of the killer whale (<i>Orcinus orca</i>) off Venezuela are scarce. Eighteen records were opportunistically collected from April 1982 through January 2008. Bottom depth for the sightings was 10-1,500 m (mean = 444 + SD = 405; mode = 400, n = 18). Five records had available associated still photographs or video. Noteworthy was a videotaped attack by two killer whales on a leatherback turtle (<i>Dermochelys coriacea</i>). Group size ranged from 1-5 individuals (mean = 2.67 + SD = 1.57; mode = 1, n = 18). Adult males were present during 67% of reported sightings; females/juveniles were present in 61% (n = 12 and 11, respectively). Pictures of two male killer whales were sent to researchers in Brazil and the Bahamas for comparison purposes. Adult males were present in 92% of reported sightings. Females and juveniles were observed during 67% of reported sightings. 83% of the records were from December through May. There is currently not enough information to speculate on any seasonality to the occurrence of this species in Venezuelan waters.原始提供方：海梅·博拉诺斯-希门尼斯（Jaime Bolaños-Jiménez） 数据集贡献方：海梅·博拉诺斯-希门尼斯 摘要： 目前关于委内瑞拉海域虎鲸（Orcinus orca）的正式目击记录较为稀少。本数据集于1982年4月至2008年1月期间通过机会性采集共获得18条记录。本次目击对应的海底深度为10至1500米（平均值=444，标准差SD=405；众数=400，样本量n=18）。其中5条记录附带可用的静态照片或视频资料。值得关注的是一段记录了两头虎鲸攻击棱皮龟（Dermochelys coriacea）的视频。鲸群群体规模介于1至5头之间（平均值=2.67，标准差SD=1.57；众数=1，样本量n=18）。67%的目击记录中存在成年雄性虎鲸；雌性与幼体虎鲸的出现率为61%（分别对应样本量n=12与n=11）。研究人员将两头雄性虎鲸的照片发送至巴西与巴哈马的科研人员用于比对分析。成年雄性虎鲸在92%的目击记录中均有出现；雌性与幼体虎鲸的观测出现率为67%。83%的记录采集于12月至次年5月。目前尚无足够信息可用于推测该物种在委内瑞拉海域的出现是否存在季节性规律。