Telemetry‐validated nitrogen stable isotope clocks identify ocean‐to‐estuarine habitat shifts in mobile organisms
Telemetry‐validated nitrogen stable isotope clocks identify ocean‐to‐estuarine habitat shifts in mobile organisms
复制标题
遥测验证的氮稳定同位素钟识别移动生物从海洋到河口栖息地的变化
DOI：
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发表时间：
2020
影响因子：
6.6
通讯作者：
Jill A. Olin
中科院分区：
文献类型：
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作者：
Oliver. N. Shipley;A. Newton;Michael G. Frisk;G. Henkes;Jake LaBelle;M. Camhi;M. Hyatt;Hans Walters;Jill A. Olin
在整个生命史中，许多动物在异质环境中过渡，以促进繁殖，觅食和躲避捕食者等行为。移动的物种所经历的动态环境和生物条件被整合到其组织的化学成分中，从而提供对运动的回顾性洞察。在这里，我们提出了氮稳定同位素时钟（“同位素时钟”）的独特应用，它整合了组织周转率，消费者稳定同位素比率和栖息地特定的同位素基线，以预测自移民以来的时间和迁徙物种栖息地转移的时间。从幼年沙虎鲨Carrias taurus（一种已知在海洋和河口环境之间进行季节性运动的物种）收集的血浆的氮稳定同位素值被用来估计自移民以来的时间和该物种进行的季节性栖息地转移的时间。对6年内采样的65条幼年沙虎鲨进行的氮同位素时钟估计表明，鲨鱼个体主要在6月至7月期间抵达河口栖息地，其中一些鲨鱼早在5月中旬就抵达。这些估计值通过比较同位素来源的河口到达时间与声学跟踪的个人进行了验证。从我们的同位素方法估计的中值河口到达日与每个采样人群的声学遥测估计一致。敏感性分析表明，同位素推断的时间，因为移民和河口抵达估计是强大的同位素周转率和饮食组织歧视因素的变化在多个建模方案。这表明，如果起源地和新地点之间存在同位素变异，氮同位素时钟的参数化可以提供可靠的移民时间和到达新栖息地的时间估计。我们的研究提出了遥测验证同位素时钟的独特应用，以获得自移民以来的时间的回顾性估计和季节性穿越异质环境的动物的栖息地转移时间。这种方法可以很容易地应用于许多时间和空间尺度，以及其他物种和生态系统，以促进快速评估动物栖息地使用和更广泛的生态系统结构的变化。
Throughout their life history, many animals transition among heterogeneous environments to facilitate behaviours such as reproduction, foraging and predator avoidance. The dynamic environmental and biological conditions experienced by mobile species are integrated in the chemical composition of their tissues, providing retrospective insight into movement. Here, we present a unique application of nitrogen stable isotope clocks (‘isotopic clocks’), which integrate tissue turnover rates, consumer stable isotope ratios and habitat‐specific isotope baselines to predict time‐since‐immigration and the timing of habitat shifts in a migratory species. Nitrogen stable isotope values of blood plasma collected from juvenile sand tiger sharks Carcharias taurus, a species known to undertake seasonal movements between ocean and estuarine environments, were used to derive estimates of time‐since‐immigration and the timing of seasonal habitat shifts undertaken by this species. Nitrogen isotopic clocks estimated for 65 juvenile sand tiger sharks sampled across 6 years indicated that individual sharks predominantly arrived to estuarine habitats between June and July, with some individuals arriving as early as mid‐May. These estimates were validated by comparing isotope‐derived estuarine arrival times with those from acoustically tracked individuals. The median estuarine arrival day estimates from our isotopic approach aligned with estimates from acoustic telemetry for each sampling population. Sensitivity analyses indicated that isotopically inferred time‐since‐immigration and estuarine arrival estimates were robust to variation in isotopic turnover rate and diet tissue discrimination factors under multiple modelling scenarios. This suggests that parameterization of the nitrogen isotopic clock provides reliable estimates of time‐since‐immigration and day of arrival into new habitats if isotopic variation exists between origin and new locations. Our study presents a unique application of telemetry‐validated isotope clocks to derive retrospective estimates of time‐since‐immigration and timing of habitat shifts for animals that seasonally traverse heterogeneous environments. This approach can be readily applied across many temporal and spatial scales, and to other species and ecosystems, to facilitate rapid assessment of changes in animal habitat use and broader ecosystem structure.
影响因子：
2.5
作者：
Galvan, D. E.;Sweeting, C. J.;Reid, W. D. K.
通讯作者：
Reid, W. D. K.