Gray Whale Senses
Hearing is the most important sense for whales in water, sound travels four times as fast as it does in air and it also travels further. Some of the sounds whales make can be heard above water, fishermen used to think that their moans and whistles were sea monsters or mermaids. They vocalize using clicks, groans, grunts, squeaks, rasps, and roars. These sounds are produced by squeezing air through the blowhole or by bursts of air from the lungs.
Since their eyes are far back on their head, gray whale vision consists of two fields on either side of the body, rather than the binocular view that humans have. There is some uncertainty about how well whales can see because their eyes are very small, (about the size of an orange) although they seem to have good eyesight in both water and air. It’s unknown whether whales can see colors or not. When near the shoreline or boats, gray whales will sometimes rise vertically out of the water, just high enough to scan its surroundings, this behavior is called spyhopping.
The anatomy of the gray whales brain shows that the sense of smell is poorly developed, baleen whales like the gray whale have small smell receptors in their nasal passages. One theory is that when they breach the whale might be positioning its blowhole toward the wind in order to get a whiff of what might be out there.
Gray whales are mostly bottom feeders, they swim to the bottom of the ocean, roll onto their side, and stick their head a few inches into the bottom. They expand and contract their throat grooves, and retract their tongue which creates suction that brings mud into its mouth. The mud is moved around a little and pushed out through the baleen, the food gets trapped by the baleen and the rest is pushed out the sides of the mouth.
Whales can get cancers, stomach ulcers, heart disease, pneumonia, jaundice, and arthritis. Sometimes whales are found stranded on beaches, possibly from illness, wave action, currents, or parasitic diseases which affect the whale’s ability to navigate.
The whale has no sense of smell, the outer ears, which in land mammals help collect the sound, have entirely disappeared. The ear openings are only the size of a pencil point. Water, unlike air, is a very good medium for carrying sound and this might explain the small ears. It also might be the reason for other methods of communication such as breeching or sounds made within the throat.