"Sperm Whales: The Stuff of Legend" by Mary Jane Schramm
S.O.S.! The call came in that a whale had stranded at the edge of the marshes behind the US Post Office Distribution Center in Richmond, in San Francisco Bay. Immediately, the Marine Mammal Center dispatched a team of medical staff and volunteers. Dark had fallen, and as our eyes adapted, we were awestruck: it was a newborn sperm whale, Physeter macrocephalus, just days old. We stabilized it as the veterinarian administered B vitamins and steroids, and took blood and tissue samples. Unable to render further help, we gently floated it towards the open water, hoping its mother might be nearby to reclaim it. A few days later it washed up dead, beneath the Bay Bridge. The initial necropsy revealed severe scoliosis, a spinal malformation. Although sperm whales live in California waters year-round, they prefer very deep waters off the Continental Shelf, so rarely do nearshore sightings occur. This was the only recorded instance of a living sperm whale entering San Francisco Bay; a tragic distinction.
THE HUNT: Sperm whales have long been prized for their high quality blubber and spermaceti for oil, their ambergris for pharmaceuticals and perfumes. When the world whaling capital shifted from New Bedford and Honolulu to San Francisco around 1880, faster steam-powered boats replaced sailing ships, and the hunt intensified. This continued, with a gradually diminishing “harvest” as whale stocks became alarmingly depleted. In 1946 the International Whaling Commission was established to regulate and keep the whaling fishery viable. Many ports had closed, but Point Molate in San Francisco Bay continued. It was with the Marine Mammal Protection Act of 1972 that American whaling was banned outright.
In the 20th century the development of plastics, the petroleum industry, and other whale product replacements made whaling even less profitable. However, the mid-20th Century gave rise to nuclear weapons - and a burgeoning pet food industry. In December, 1971 the Kal Kan pet food company commissioned a final whale hunt into the Gulf of the Farallones off San Francisco, killing a sperm whale--the last to be hunted commercially under the U.S. flag. The meat went for Fido. The precious spermaceti oil was sold to the nuclear industry for weapons and electricity production.
LEVIATHAN! Legendary in sailor’s tales and Melville’s Moby Dick as "the great leviathans," sperm whales are superlative creatures. They are the largest toothed predator on the planet. Males can reach a length of sixty-two feet, weighing upwards of fifty tons. They dive to over 7,300 ft., deeper and longer than any other whale except the Cuvier’s beaked whale. The distinctive, huge “boxcar” head contains the largest brain on Earth, although much of it is used to process sounds such as echolocation and vocalizations. Large (even giant) squid, octopus, sharks, and other fish comprise their diet. The California/Oregon/Washington sperm whale stock is found in highest numbers from April through mid-November, coinciding with peak prey abundance.
A WHALE OF DISTINCTION: Like most toothed whales, sperm whales have complex, highly structured societies in which individuals play specific roles. New mothers are attended by ‘aunties’ who share care-giving of young calves who must remain at the surface while Mom dives deep to feed and replenish her energy stores. She has nursed her calf with incredibly fat-rich milk. They give birth at four-plus year intervals, sometimes caring for calves for nearly a decade. After mating with the females, who live in groups with immature males in temperate and tropical latitudes, sperm whale bulls retire to high-latitude waters. They are a cosmopolitan species, found worldwide. Killer whales are their only natural enemies.
SURVIVAL! Current conservation threats include vessel strikes, entanglement in fishing gear, human-generated noise, and bioaccumulation of pollutants. NOAA and our national marine sanctuaries work to reduce these threats through protective legislation for the whales and their habitats.
Photo: Top: Whale cow and calf. Credit: NOAA. Second from top: Aerial shot shows distinctive huge head, bubbles coming from offset blowhole. Credit: Tim Cole/NMFS ***; Third from top: Ilustration: Squid and sperm whale battle. Credit: Wikimedia Commons. Above : Stranded whale's bulbous forehead and narrow, toothed lower jaw in foreground.
Learn more about sperm whale biology, society, ecology and conservation at: https://www.fisheries.noaa.gov/species/sperm-whale and hear their vocalizations at: https://swfsc.noaa.gov/textblock.aspx?Division=PRD&ParentMenuId=148&id=5776.
Editor's Note: The photograph (above) documents a necropsy done on a sperm whale at Limantour in the Pt. Reyes National Seashore. Our regular contributor, Mary Jane Schramm, is in the dark blue NOAA jumpsuit, pulling away a slab of blubber to expose the innards and determine cause of death. There was garbage and a huge wad of fishing net blocking its pylorus, a valve between the stomach and intestines. As Mary Jane said, "So sad".