Collaborative Research: At-sea experimental disturbances to characterize physiological plasticity in diving northern elephant seals

海洋动物必须与持续的环境变化和海洋中人类活动的增加作斗争。干扰可以影响海洋哺乳动物的行为，但相关的生理成本仍然未知。由于它们令人印象深刻的潜水能力是基于专门的生理学，因此生理成本可能限制并定义了海洋哺乳动物对干扰的敏感性。该项目将通过使用引起对噪音反应的实验性海上干扰来调查北方象海豹潜水生理的变异性-噪音是全球关注的压力源。这些方法建立在最先进的测井技术基础上，并将开发一种新的探头，能够检测体内的氧气管理。将在常规潜水期间测量海豹的心血管生理学和氧气使用，并与在海上经历远程实验干扰的动物进行比较。该项目的目标是了解该物种的生理范围和限制，并提供数据，可以预测海洋哺乳动物对自然和人为压力的恢复力。这些数据将对敏感的生态系统和其他不易研究的物种产生广泛影响。它将直接适用于海洋物种和生境的养护和管理。该项目将培训本科生，研究生和博士后研究员，并将包括通过州立公园和公共水族馆进行广泛的公众宣传。环境变化，包括噪音污染，是对海洋生态系统的结构和可持续功能的根本挑战。该项目的目标是确定潜水海豹氧气管理的生理变化，这些变化可以直接与海洋中的个人成功联系在一起。该项目的三个目标将通过综合测量心血管生理学（心电图和血液或肌肉中的氧传感器），同时收集时间深度记录和三维加速度数据来解释水下活动，利用从迁移的幼象海豹那里收集的海上数据来实现。目标1将通过描述心率、血氧消耗、肌肉灌注和精细尺度潜水行为之间的相互关系，提供公海潜水表型的第一个全面图片。它还将评估具有不同水下氧气需求的肌肉灌注能力的分子标志物。目标2 - 3是基于实验诱导在许多水生物种中观察到的声干扰的行为效应-延长潜水时间和增加运输成本。这两个目标将检查氧气管理策略，以应对刺激。比较自然与扰动潜水允许评估个人可塑性的潜水表型，结合行为和生理。这是确定模式物种扩展潜水能力的关键第一步，它们对自然潜水模式海上中断的反应，并最终预测它们无法补偿的干扰阈值。

Marine animals must contend with ongoing environmental shifts and increased human activities in the ocean. Disturbances can affect the behavior of marine mammals, yet associated physiological costs remain unknown. Because their impressive capacity for diving is based on specialized physiology, it is likely that physiological costs limit and define the sensitivity of marine mammals to disturbances. This project will investigate variability of dive physiology in northern elephant seals by using experimental at-sea disturbances that elicit responses to noise - a stressor of global concern. The methods build on state-of-the-art logging technologies and will develop a new probe that will be capable of detecting oxygen management in the body. Cardiovascular physiology and oxygen use of the seals will be measured during routine diving, and compared with animals that experience a remote experimental disturbance while at sea. The project goal is to understand the physiological range and limits of this species, and to provide data that could predict marine mammal resilience to natural and anthropogenic stressors. These data will have wide-reaching implications for sensitive ecosystems and other species of concern that are not easily studied. It will be directly applicable to conservation and management of marine species and habitats. The project will train undergraduates, graduate students and a postdoctoral researcher, and will include extensive public outreach via state parks, and a public aquarium. Environmental changes, including noise pollution, represent a fundamental challenge to the structure and sustainable function of marine ecosystems. The goal of this project is to identify physiological variability in the oxygen management of a diving seal that can be directly linked to individual success in the ocean. The project's three objectives will be achieved using at-sea data collected from translocated juvenile elephant seals, via integrated measurements of cardiovascular physiology (EKG and oxygen sensors in blood or muscle) with simultaneously collected time-depth records and 3-dimensional acceleration data to interpret underwater activity. Objective 1 will provide the first comprehensive picture of the dive phenotype in the open ocean by characterizing interrelationships among heart rate, blood oxygen depletion, muscle perfusion, and fine scale dive behavior. It will also assess molecular markers of perfusion capability in muscles with different underwater oxygen demands. Objectives 2 & 3 are based on experimentally inducing the behavioral effects of acoustic disturbance observed in many aquatic species - extended dive durations and increased cost of transport. Both objectives will examine oxygen management strategies in response to stimuli. Comparing natural versus perturbed dives permits an assessment of individual plasticity in the dive phenotype, incorporating behavior and physiology. This is a critical first step in determining the capacity of a model species to extend diving, their response to at-sea disruptions in natural dive patterns, and, ultimately, to predict thresholds of disturbance beyond which they cannot compensate.