Neises Victoria M, Karpovich Shawna A, Keogh Mandy J, King Ryan S, Trumble Stephen J
Department of Biology, Baylor University, Waco, TX 76798, USA.
Alaska Department of Fish and Game, Fairbanks, AK 99701, USA.
Conserv Physiol. 2021 Jun 8;9(1):coab036. doi: 10.1093/conphys/coab036. eCollection 2021.
Alaskan harbour seal populations are currently listed as a species of special concern. Although there is evidence of recent stabilization or even partial recovery of harbour seal numbers in areas of historic decline, most populations have not made substantial recoveries. To date, few data exist regarding spatial and seasonal changes in blubber fatty acids (FAs) for Alaskan harbour seal populations. The purpose of this study was to qualitatively investigate harbour seal blubber FA profiles for regional, seasonal and age class differences. Blubber FA concentrations were analysed using MANOVA and linear discriminant analysis (LDA) from 760 individual harbour seals across Bristol Bay, Kodiak, Prince William Sound and Southeast Alaska from 1997 to 2010. Our results suggest spatial and seasonal differences are largely driven by monounsaturated FAs, most notably 14:1n-5, 16:1n-7 and 18:1n-7. In addition, our data revealed a progression in blubber FAs from pups to adults, with a shift from saturated FAs and short-chained monounsaturated FAs in the pup blubber to more long-chain monounsaturated FAs and polyunsaturated FAs in adults. Lastly, harbour seals pups had elevated saturated FA 16:0 concentrations when compared to other age classes, regardless of location or period. With this vast spatial and seasonal FA information, we believe future sampling of blubber FAs from Alaskan harbour seal populations could be a useful tool in assessing the response of this species and its ecosystem to changes associated with natural and anthropogenic pressures.
阿拉斯加港海豹种群目前被列为特别关注的物种。尽管有证据表明，在历史上数量下降的地区，港海豹数量最近趋于稳定，甚至部分有所恢复，但大多数种群尚未实现大幅恢复。迄今为止，关于阿拉斯加港海豹种群脂肪脂肪酸（FAs）的空间和季节性变化的数据很少。本研究的目的是定性调查港海豹脂肪FA谱的区域、季节和年龄组差异。使用多变量方差分析（MANOVA）和线性判别分析（LDA），对1997年至2010年期间来自布里斯托尔湾、科迪亚克、威廉王子湾和阿拉斯加东南部的760只港海豹个体的脂肪FA浓度进行了分析。我们的结果表明，空间和季节差异在很大程度上是由单不饱和脂肪酸驱动的，最显著的是14:1n-5、16:1n-7和18:1n-7。此外，我们的数据显示，从幼崽到成年海豹，脂肪中的脂肪酸有所变化——幼崽脂肪中的饱和脂肪酸和短链单不饱和脂肪酸向成年海豹中更多的长链单不饱和脂肪酸和多不饱和脂肪酸转变。最后，无论位置或时期如何，港海豹幼崽的饱和脂肪酸16:0浓度都高于其他年龄组。有了这些丰富的空间和季节性脂肪酸信息，我们相信，未来对阿拉斯加港海豹种群脂肪脂肪酸的采样可能是评估该物种及其生态系统对自然和人为压力相关变化的反应的有用工具。
