apparently one whale years ago was observed doing this for hours and now more and more whales in the area are seen copying it so we think it’s a whole new behavior and it seems to be a response to shrinking food sources.
Instead of expending any energy actively hunting, the whale just holds its mouth open wherever fish are being hunted by birds. To escape the birds, the fish try to hide in the whale’s mouth because it’s a darker area that looks like shelter.
…They’re turning into giant, sea-mammal pitcher plants.
What is interesting is there is a heron (black heron) that hunts via similar methods (using shade as bait for fish). I do not think it is a learned behavior for them though. Paralel evolution is buck wild. You can reach similar outcomes through wildly different evolutionary methods and paths. Eg - in whales it is their big brains at work - with herons it is instictual - and with pitcher plants it is automatic.
Yeah little creatures love to hide so a number of predators have taken advantage of that and what’s EXTRA fucked up is that another example includes a starfish:
