Migrating blue whales rely on memory to find their feeding grounds

Breakfast spots, coffee shops, and watering holes pepper the daily commutes of modern urban humans, but we try to remember the ones where we get the best food or drinks. If we do longer journeys routinely, we also keep track of the best grazing grounds—a diner, a gas station with the best snacks, and so on.
Blue whales, according to research published in PNAS this week, seem to make similar mental notes. On their annual migration, their path takes in the spots that have proven to be the most reliable feeding grounds over the years. In doing this, the whales may bypass hotspots that pop up and fade from one year to the next, suggesting that they rely heavily on memory to find a solid meal. But in a world where “normal” is shifting rapidly, the endangered whales may no longer be able to rely on the abundance of those old, faithful feeding grounds.
Why do whales go where they go?
Blue whales are the largest animal that we know to have lived, and that means they need colossal amounts of food. Despite this, they’re picky eaters, feeding almost exclusively on small crustaceans called krill, which they eat by lunging through a large swarm with an open mouth, trapping the animals in their mouths while the sea water filters back out. And they manage to find sources of food while migrating from a summer near the poles to a winter spent closer to the equator.
Read 9 remaining paragraphs | Comments