You’re out on the water in Frederick Sound and hear a blowing sound in the distance.
Grabbing your binoculars, you scan the horizon and see the back of a large creature break the surface–but something’s different this time. The animal is really close to shore and the back is bumpy, almost like an alligator’s. Is this a giant transplant from the Florida Everglades? Not likely. You may be looking at a gray whale, a unique visitor to our inside waters.
Hi, I’m Sunny Rice for the Petersburg Marine Mammal Center.
Gray whales are a similar size as a humpback, but have a triangular, rather than flat head-shape, and much broader and shorter flippers. These are adaptations to the gray whales’ unique lifestyle. They are the only whales that feed on benthic, or bottom-dwelling, animals. They gather small sand flea-like creatures called amphipods and other crustaceans into their mouths by dredging through the mud and filtering it through their baleen. In fact, they are often seen at the surface with mud streaming from their mouths.
Like humpbacks, gray whales make long annual migrations, up to 5000 miles. They travel back and forth between their winter calving areas off the coast of Baja California and their summer feeding grounds in Alaska. Most spend their summers in the Bering, Chuckchi and Beaufort Seas, but some stay in the waters off British Columbia and Southeast Alaska.
It is that feeding style and migration that may be causing the unusual number of gray whale mortalities observed recently all along the West Coast. Since Spring of 2018, upwards of 200 dead whales have been spotted on beaches from Mexico to Alaska, and virtually all of them were severely emaciated. This indicates that they are having difficulty obtaining food on their summer feeding grounds. One theory to explain this is that decreasing sea ice has favored mid-water organisms, and led to a decline in the bottom-dwelling amphipods gray whales target. A definite cause for concern, but mortality events like these have also happened in the past and the population continued to thrive, so hopefully we’ll be seeing these mottled gray giants in our waters for years to come.
