The Northern Yellowstone elk herd, one of the most famous and closely watched in the world, is finally growing at a healthy clip.

An annual winter aerial survey conducted by Montana Fish, Wildlife and Parks and Yellowstone National Park biologists counted 7,579 elk over two days in January, up a whopping 42 percent from last winter’s 5,349 elk.

The sizable increase over last year is likely due to the inconsistency in the ability to see animals from the air, said Karen Loveless, an FWP biologist based in Livingston who flies part of the survey area. Studies have shown the accuracy of aerial counts can vary from 65 to 90 percent, depending…