Marine animals are exposed to a rising tide of human impacts including ocean noise, pollution, global climate change, ship traffic and entanglement in fishing gear. All of these factors can increase stress levels, which can have profound negative effects on immunity, health, reproduction and survival. In our Marine Stress Research Program, Aquarium scientists are developing new methods of evaluating stress in marine wildlife to identify, assess and ameliorate the stressful impacts of human activities. We are already working on several species of whales and sea turtles, and are planning work on seabirds, fish, and sharks.
- Develop new methods of assessing stress in marine wildlife
- Identify the major sources of significant human-caused stress in the marine environment
- Evaluate how human-caused stress is affecting health, reproduction and survival in marine wildlife
Novel Hormone Assays for Marine Wildlife
Our laboratory has pioneered the development of hormone assays for whales and sea turtles. In North Atlantic right whales, measurement of reproductive hormones can identify a whale's sex, maturity and reproductive state (pregnancy, lactation). We have found that right whale fecal "stress hormones" (glucocorticoids) elevate in response to severe fishing gear entanglement, poor health and shipping noise. A new test for thyroid hormones should provide us with the first measure of nutritional stress for baleen whales. We have developed several new hormone assays for measuring stress in sea turtles.
Population Consequences of Acoustic Stress in Right Whales
Levels of underwater noise from shipping, seismic exploration, military sonar and other sources have increased dramatically over the past 50 years. Whales subjected to high levels of noise may have difficulty communicating and finding food, and may be driven from preferred feeding habitats. What sort of impacts might acoustic stress have on the population over the long term? Using data from our long-term study on North Atlantic right whales, we are integrating information on physiology, health and life history to evaluate the effects of ocean noise on the health, reproduction and survival of this endangered population.
Assessing Stress in Deep-Diving Whales of the Bahamas
In collaboration with the Bahamas Marine Mammal Research Organization (BMMRO), we are developing fecal hormone assays for two populations of deep-diving whales in the Bahamas, Blainville's beaked whales and sperm whales. Beaked whales are sensitive to military sonar, while sperm whales co-occur with beaked whales but appear to be less impacted. The goal of this study is to develop fecal hormone assays for both species to assess stress from acoustic disturbance.
Respiratory Sampling in Whales—A Novel Method of Assessing Stress
Many of our research projects involve measurement of hormones in whale fecal samples, but these samples can only be collected opportunistically. But large whales regularly produce another type of sample: large clouds of respiratory vapor (blow). This vapor contains measurable amounts of hormones, and may provide another non-invasive method for studying stress in large whales. In 2011, we successfully collected blow vapor from North Atlantic right whales using a customized blow-collection apparatus, and have detected stress-associated hormones and reproductive hormones in these samples. We will test this technique next with humpback whales.
Cold-Stunning Stress in Sea Turtles
Every fall, the New England Aquarium treats dozens of endangered Kemp’s ridley sea turtles that have washed up cold-stunned—chilled and unable to swim—on Cape Cod. In collaboration with the Aquarium's Rescue and Rehabilitation and Animal Health departments, we are studying hormone responses to stress in these cold-stunned turtles. We have found that two hormones (corticosterone and thyroxine) change dramatically during recovery, and that trends in both hormones correlate with important clinical measures and behaviors.
Read about the Right Whale Conservation Medicine program here.