Grey whales grow up to 14.6 m long and can weigh up to 30,000 kg. The light and dark grey patterns on their bodies are unique to each individual. Scientists use these patterns and the spacing of the cartilaginous “knuckles” along their lower spines to identify individuals. Their skin is covered with whale lice and a species of whale barnacle that exists only on grey whales. Grey whale barnacles time their reproduction with the grey whale breeding and calving season, increasing the chances that their larvae will be able to find a whale to land and grow on.
There are two populations of grey whales, one in the Eastern North Pacific Ocean, and a smaller population in the Western North Pacific Ocean (Atlantic grey whales were hunted to extinction in the 18th century). Eastern grey whales have the longest migration of any mammal, migrating up to 9,000 km each way between their feeding grounds in the Bering Sea and Alaska and their breeding grounds in Baja, California and Mexico. Like humpback whales, grey whales do not eat in the winter, living off of their fat stores during this time.
Grey whales are the only baleen whale species that eats primarily bottom-dwelling organisms. They feed by rolling onto their sides and sucking mud into their mouths and filtering out small crustaceans and fishes with their baleen. Like humans, grey whales exhibit laterality, or “handedness.” Individual whales will typically feed on the same side every time, and have associated scratches and fewer barnacles on the side that goes through the mud.
|
Call Types |
Description |
Durations (seconds) |
Frequency Ranges |
Source Level (dB with reference to 1 micropascal) |
|---|---|---|---|---|
|
Clicks, knocks, metallic bong (“pong-pong”) |
Broadband pulses |
1 |
100Hz to 3kHz |
142 to 185 |
|
Moans |
|
1.5 |
20Hz to 200Hz |
|
Mysticeti
Mysticetes are some of the largest animals on Earth, and they eat some of the smallest animals in the ocean. Instead of teeth, mysticetes have flexible, hairy keratin plates called baleen. They take large gulps of water and filter it through their baleen, eating the plankton, krill and small fish left behind. They were heavily hunted in the 17th to 20th centuries for oil, and their baleen had many uses, including collar stiffeners and corset stays. Many mysticetes are migratory. 7 of the 15 Mysticeti species inhabit the eastern North Pacific. Some mysticete species may be threatened by climate change, because some species depend heavily on plankton as a food source; plankton abundance and distribution is affected by changes to the ocean associated with climate change.
Ocean Networks Canada has recorded the following Mysticete species:
- Humpback Whale
- Grey Whale
- Fin Whale
- Blue Whale
