Gray Whales are baleen (filter-feeding) whales which are seen regularly along the California Coast each year during their migration. Like most of the larger baleen whales, they migrate each summer to cold, productive, Arctic waters to feed, returning to protected Mexican lagoons each winter for breeding and calving. Pregnant females lead the way on the South-bound journey, anxious to get to the protected lagoon and give birth. The calf must be born in warm water as it is missing a thick layer of blubber to protect it from the cold. Females with calves lag behind on the northward migration, following the shoreline closely to avoid predators. Whales travel southbound from December through February, northbound March through May. The whales are recognized by having a low, heart-shaped blow, their mottled grey color, and lack of a dorsal fin. A dorsal ridge with several bumps goes down the center of the back. There are several excellent places for whale watching. Two well-known spots are the Pacifica pier and the Pigeon Point Lighthouse. Be prepared to spend some time at these places looking for the whales. As always along the coast, the weather can change dramatically, so wear layers.

Marine Mammals Page

Elephant seals are the largest of the pinnipeds, weighing in at 2000 pounds (females) and up to 6000 pounds for males. They spend a majority of their time at sea, but like all pinnipeds, they must come on shore to breed. Breeding season for the elephant seals is December through March, with males returning to land in early December to establish a dominance hierarchy. A scarred, calloused chest is evidence of intense battles between males. Very few males mate during any given season, guarding their harem of up to 50 females intensely. Females give birth about a year after mating, although gestation time of the developing fetus is only 9 months! Delayed implantation of the embryo ensures that females will give birth at the same time of year every year. This allows males to predict when the females will be on land so they can mate with them again the next year. Newborn pups are weaned after about 27 days, then females are ready to mate again. The pup, meanwhile, is left on its own to learn to swim and catch fish. One of the the best places to view elephant seals is at Ano Nuevo Point along the San Mateo County coast. A reservation is required during breeding season, but the molting season (June through August) is open to visitors and free.

Marine Mammals Page

Sea otters are rarely seen north of Ano Nuevo Island, although they are making a comeback to the northern San Mateo County Coastline. To see wild sea otters, one of the best places is in Carmel, California at Point Lobos State Preserve. Often you will hear the otter before seeing it; the clackety clack of the rock pounding on the mussel to open it is a sure sign that sea otters are near.

Sea Otters are the smallest of the marine mammals and they are unique among marine mammals in that they do not have a thick layer of blubber for insulation. Small animals have a higher surface area to volume ratio than larger animals. This means that they tend to lose more of the body heat that they produce. Living in water can also be a problem since water draws heat away from the body much faster that air. Thermoregulation of the sea otter is accomplished in two ways. They have a thick fur coat: approximately 300,000 hairs per square inch. This makes it one of the thickest fur coats of all the mammals. Air is trapped by the fur, providing insulation. A high metabolic rate helps them to produce more body heat. They eat approximately 25% of their body weight each day. Sea otters are one of the few animals to use tools. They will dive to find their food, returning to the surface with their dinner, usually a shellfish of some sort, and a rock to use in opening it.

Marine Mammals Page