For more than a century, gray seals were hunted in the New England area. Massachusetts even paid bounties of $5 each for the seals’ valuable fur. The populations of these seals were decimated. In 1972, conservationists hoped the newly passed Marine Mammal Protection Act would bring the gray seal numbers back up. But until now, it had been difficult to know how much success it was having. A recent survey used Google maps and data from tagged animals to estimate the number of gray seals at between 30,000 and 50,000 in the New England area. Previous surveys were much lower, at around 15,000. The research team is calling it a “conservation success.”

Read more about gray seals and conservation efforts.