Blue whales regularly migrate between the Northeast Pacific to the coast off of Central America .
They breed in the South and spend the rest of their time in the North. But traveling between these locations can be difficult. Their migration path takes them through areas with heavy traffic, which increases the chances that they will be struck by a boat.
Despite the danger, whales continue to migrate.

Blue whales are huge! And they need a lot of food to support their mass. This is the main reason that the whales migrate.
Krill — which is a small crustacean whales eat — are abundant in the North after mating season.
Whale singing changes when they travel.

A recent study published in Current Biology found that when whales begin to migrate, they switch from singing at night to singing during the day. This provides a real-time signal that tells us when whales are about to migrate.
This information can help predict when whales might start swimming into waters that have a lot of boat traffic.
Understanding the whales’ songs will help predict where they will be.

Underwater microphones allow us to listen in on the whales’ songs. If we can learn more about what the songs say about the whales behavior, we could better predict where and when they will travel.
We do know some things about the whales’ songs.

So far, it seems like when whales in the North run out of food, they signal that they plan to head south. Tagged whales stopped feeding in late fall before heading south. Once they stopped eating, they changed their song within a day and started heading south.
Changes in whale songs could alert ships that blue whales are entering their area.

William Oestreich, a researcher that worked on the study, told Popular Science , “[p]otentially we could give some advance notice to folks managing these ecosystems in southern California that, hey, we’re hearing the blue whales start to migrate south, you might have a lot of them showing up here quite soon.” This could help to reduce the number of whales that die by being hit by a boat.
Better communication between blue whales and humans will help everyone share the oceans.
h/t: Popular Science
Last Updated on October 6, 2020 by Jennifer Seaton