May 29, 2019 — Whale researchers in New England believe they’ve found a new way to measure the amount of stress felt by whales when they experience traumas such as entanglements in fishing gear, and they say the technique could help protect the massive sea creatures from extinction.
The scientists, with the New England Aquarium in Boston, said the method involves measuring stress hormones by studying baleen, the bristly filter-feeding system in the mouths of the biggest whales on the planet. The baleen serves as a record that shows a spike in stress hormones when whales encounter threats such as a changing climate, ship strikes and entanglements, lead author Rosalind Rolland said.
Scientists can use the data to read the stress levels a whale experiences over the course of many years, somewhat similar to reading the rings on a tree. The data is important because whales experiencing more chronic stress are less likely to reproduce, and they can become more susceptible to disease — a bad combination for populations that are perilously low.
“A whale responding to any type of stressor could be interacting with a ship. It could be fishing gear. It could be environmental changes that stress the whale out,” Rolland said in a telephone interview. “This shows the stress hormones are related to what was going on with the whale.”