Development of blow hormone quantification for Blainville beaked whales to provide physiologic data to better inform PCoD models
Abstract
Behavioral changes have been documented in beaked whales (family Ziphiidae) in response to naval sonar exposure, raising serious con cern for the conservation of beaked whale species inhabiting Navy testing ranges or exposed to Navy exercises. To better forecast th e potential impacts of non-lethal repeated disturbance to exposed populations, models investigating the Population Consequences of D isturbance (PCoD) have been developed to predict effects of naval sonar and other stressors. However, for beaked whale species, thes e models often lack data on physiological responses and vital reproductive parameters (such as the duration of gestation), which can hinder model assumptions and outcomes. Furthermore, it is unknown whether periodic and repetitive naval sonar exposure leads to chr onic stress responses in exposed beaked whale populations, which can alter behavior and physiology, reduce resistance to disease, in hibit reproduction, and ultimately, affect population survival. Given the challenges of studying an elusive, deep-diving species and the importance of obtaining precise data, there is a need to advance technologies that will address significant gaps in our knowled ge and improve our assessment of how beaked whales physiologically respond to acoustic disturbance. Previous hormone studies conduct ed on Blainvilles beaked whales (Mesoplodon densirostris) whales have relied on fecal samples collected opportunistically after def ecation or blubber samples collected using biopsy darting. Despite the contributions of these sampling methodologies, there remains a need for a more accessible technique that permits repeated sampling of targeted beaked whales, across life history stages, and in differing disturbance scenarios. Here, we plan to develop the use of respiratory vapor (blow) to measure hormones to assess reprod uctive and stress responses of Blainvilles beaked whales (Md). The goal of the proposed work is to develop a new method that will g enerate physiological data to improve model forecasts for understanding the impacts of disturbance on beaked whales and help support management decision making for populations residing on Navy ranges. Our project will focus on the well-studied population of photo- identified Md whales, off Abaco, The Bahamas, involving individuals known sex, age class, and reproductive states. Notably, adult fe males in this population exhibit long-term site fidelity with high within-year re-sighting rates, providing the opportunity to colle ct repeat blow samples from individuals. We will conduct 30 d of fieldwork for two field seasons over FY2019 and FY2021, prioritizin g weather conditions that are optimal for blow sampling beaked whales. Samples will be collected from Md whales using a handheld ca rbon fiber pole (7 m long), which will improve agility and reach for sample collection and will also be a more transferrable applica tion for other researchers. Hormones will be extracted from samples using our established protocols and commercially available enzym e-immunoassay kits will be used for analyses. Such data could improve model forecasts for understanding the impacts of disturbance o n beaked whales and help support decision making for populations residing on Navy ranges.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 07, 2021
- Source ID
- N000142112903
Entities
People
- Elizabeth Burgess
Organizations
- New England Aquarium
- Office of Naval Research
- United States Navy