Countdown: one week

I'm getting ready to head to the Bering Sea, the icy waters between Alaska and Russia. My destination: a 420-foot-long Coast Guard icebreaker called the Healy. Starting in early May, this ship sailed north from Dutch Harbor, Alaska. The Healy will sail back and forth across a planned route so scientists can study the marine animals in the Bering Sea waters.

In recent years, the researchers have discovered that the water and air temperatures are rising. Warmer temperatures affect the balance of the marine ecosystem.

In the Bering Sea, bearded seals, walruses and diving birds feed on bottom-dwelling critters. Scientists think warmer waters may encourage fish to swim farther north to compete for food with the seals, birds and walruses. Using water tubes, nets and their own eyes, the scientists are gathering samples and details to find out if their hunch is correct. Stay tuned...