Today was the fourth and final full day of our expedition in Southeast Alaska. The day started with anticipation and excitement as we woke up in remote Pavlof Harbor, ready to take the Zodiacs to Sanak Island. The wildlife made its presence known as we explored the island with a moderate hike and a brief kayak excursion.

After lunch on the ship, a few brave souls returned to the Zodiacs wearing little more than a bathing suit for the polar plunge. Some passengers had dramatic water entries, and all were quick to get out of the frigid sea.

Once everyone was back on National Geographic Sea Lion and before dinner, one of the naturalists made an unforgettable sighting. Humpback whales were breaking the surface of the ocean in pursuit of prey. These whales coordinate efforts to swim through a school of fish, gathering as many as possible in a single mouthful. First, a single whale encircles the school of fish, expelling air bubbles underwater to form a barrier from which the panicked fish cannot escape. Another individual swims up from below the trapped fish, using a specific vocalization to drive the frightened fish into an even tighter shoal at the water’s surface. The group swims in unison through the tightly packed fish, mouths open wide.

This group of whales repeated the hunting strategy several times, and passengers were able to take a long look and enjoy one of nature’s greatest sights. Today was a fine day to explore Southeast Alaska.