The massive annual spring migration of America's birds – millions of them – is underway. Here's how to follow along at home.

The massive annual spring migration of America's birds – millions of them – is underway. Here's how to follow along at home.

The arctic tern may look small and delicate ... The basking shark is the second largest fish in the world. Their migration routes remain a bit of a mystery. They can be spotted off the coast ...

Fall migration is generally between Aug ... Some species include the arctic tern, Hudsonian godwit, long-tailed jaeger and the bobolink. The blackpoll warbler songbird can fly as far from Alaska ...

Migration won't peak in New Hampshire until ... Some species include the arctic tern, Hudsonian godwit, long-tailed jaeger and the bobolink. The blackpoll warbler songbird can fly as far from ...

This is the longest migration by land of any mammal on Earth ... At the top of the list is the arctic tern. It has been recorded migrating over 44,000 miles, flying from the Arctic to Antarctica.

Talk about an incredible journey! Arctic terns hold the record for the farthest migration. One trip from their breeding grounds in the Arctic to their winter territory in Antarctica is about ...

Meet nature's endurance champions: Humpback whales, spanning up to 8,000 km; Albatrosses, traveling 75,000 miles annually; Caribou migrating 1,500 miles; Arctic Terns, covering 44,000 miles round ...