Where the whales are

A relatively fresh coastal current carrying tiny marine organisms called copepods flows into the Great South Channel. The current collides with saltier, denser water to form an ocean front. The denser, saltier water sinks beneath the lighter, fresher water. Copepods sinking with the water swim back toward the surface, aggregating in dense patches along the front. (Amy Caracappa-Qubeck, Woods Hole Oceanographic Institution)