Geographic range size, water temperature, and extrinsic threats predict the extinction risk in global cetaceans
Geographic range size, water temperature, and extrinsic threats predict the extinction risk in global cetaceans
复制标题
DOI：
10.1111/gcb.16385
复制
发表时间：
2022-08
影响因子：
11.6
通讯作者：
Chuanwu Chen;T. Jefferson;Bingyao Chen;Yanping Wang
中科院分区：
文献类型：
--
作者：
Chuanwu Chen;T. Jefferson;Bingyao Chen;Yanping Wang
尽管鲸目动物为水生生态系统的健康和稳定做出了重大的生态贡献，但许多物种仍处于高度濒危状态，近三分之一的物种被评估为濒临灭绝。然而，到目前为止，很少有研究明确研究的模式和过程的灭绝风险和威胁，这一分类群，甚至更少的两个亚支（Mysticeti和Odontoceti）之间。为了填补这一空白，我们编制了一个数据集，其中包括六个内在特征（活动区域，地理范围大小，体重，潜水深度，学校规模和生殖周期），六个与海面温度和叶绿素浓度相关的环境因素，以及两个与人类相关的威胁指数，这是鲸类动物普遍认可的。然后，我们采用系统发育广义最小二乘模型和模型选择，以确定在所有鲸目动物的灭绝风险的关键预测，以及在两个分支。我们发现，地理范围的大小，海面温度和人类威胁指数是最重要的预测灭绝风险的所有鲸类和齿鲸类。有趣的是，最大体重与神秘鲸的灭绝风险呈正相关，但与齿鲸的灭绝风险呈负相关。通过将七种主要威胁类型与灭绝风险联系起来，我们进一步揭示了渔业副渔获物是最常见的威胁，但当考虑所有物种而不仅仅是受威胁物种时，某些威胁的影响可能会被高估。总的来说，我们建议保护工作应侧重于小型鲸类动物和生活在温暖沃茨或强大的人为压力下的物种。此外，进一步的研究在叠加风险图和量化风险严重程度时应考虑物种的受威胁状况。最后，我们强调，应采取不同的保护策略，因为它们的灭绝风险模式和主要威胁类型有很大的不同。例如，大型的神秘鲸和小型的齿鲸需要特别优先保护。
Despite the fact that cetaceans provide significant ecological contributions to the health and stability of aquatic ecosystems, many are highly endangered with nearly one‐third of species assessed as threatened with extinction. Nevertheless, to date, few studies have explicitly examined the patterns and processes of extinction risk and threats for this taxon, and even less between the two subclades (Mysticeti and Odontoceti). To fill this gap, we compiled a dataset of six intrinsic traits (active region, geographic range size, body weight, diving depth, school size, and reproductive cycle), six environmental factors relating to sea surface temperature and chlorophyll concentration, and two human‐related threat indices that are commonly recognized for cetaceans. We then employed phylogenetic generalized least squares models and model selection to identify the key predictors of extinction risk in all cetaceans, as well as in the two subclades. We found that geographic range size, sea surface temperature, and human threat index were the most important predictors of extinction risk in all cetaceans and in odontocetes. Interestingly, maximum body weight was positively associated with the extinction risk in mysticetes, but negatively related to that for odontocetes. By linking seven major threat types to extinction risk, we further revealed that fisheries bycatch was the most common threat, yet the impacts of certain threats could be overestimated when considering all species rather than just threatened ones. Overall, we suggest that conservation efforts should focus on small‐ranged cetaceans and species living in warmer waters or under strong anthropogenic pressures. Moreover, further studies should consider the threatened status of species when superimposing risk maps and quantifying risk severity. Finally, we emphasize that mysticetes and odontocetes should be conserved with different strategies, because their extinction risk patterns and major threat types are considerably different. For instance, large‐bodied mysticetes and small‐ranged odontocetes require special conservation priority.