If you’ve ever tried moving a piano, you may recall that it took a small army of people to get it from one spot to another. It’s backbreaking work, but no worse than what some marine biologists experience when having to manually weigh a gray seal to monitor its health. The mammals weigh between 400 and 550 lbs. on average—about the same heft as an upright piano—and have to be captured by net and hoisted by a tripod several feet off the ground for the weigh-in.
Scientists need accurate measurements of body size, mass, and blubber in order to track the health and stability of gray seal populations from one season to the next. But capturing them can be stressful to the animals, and working with such large animals means they often need to be sedated first.
Michelle Shero, a scientist at Woods Hole Oceanographic Institution (WHOI), is helping to change the paradigm. She’s applying a new aerial photography-based approach for measuring the earless seals, alongside researchers at the Canadian Department of Fisheries and Oceans as well as Duke University.
“We’ve been using drones to get weight estimates of gray seals without ever having to touch them,” said Shero. “It’s a totally non-invasive way of measuring the animals, so it eliminates the stress of capture. And, it makes the whole process a lot easier, faster, and inexpensive.”
Read more at Woods Hole Oceanographic Institution
Photo: Marine ecologist at Woods Hole Oceanographic Institution is exploring new, non-invasive approaches to measuring the body mass of gray seals. (Photo by Michelle Shero, Woods Hole Oceanographic Institution)