Grey Whales: A Conservation Success?

Gray whale. Photo: NOAA

By Mary Jane Schramm

Right around the winter solstice, we see the first wave of the southbound gray whale migration passing our shores from their Arctic feeding grounds to their Mexican breeding grounds. The Eastern Pacific stock of this species will travel nearly 12,000 miles round-trip, returning north in the spring.

In the 1940's, at the end of whaling, gray whale numbers had plummeted to perhaps only 3,500 animals worldwide. No one knows how large the pre-whaling population was, but researchers at Stanford University now suggest they may have once numbered over 100,000.

With legal protections their numbers rebounded until in 1994, when their population reached approximately 20,000, and they were removed altogether from the Endangered Species List. Their numbers climbed to around 26,600 in 1999.

The gray whale has been much-vaunted as a conservation success story. But there have been recent signs that not all is well.

Beginning in 1999 and 2000, approximately one third of the gray whale population disappeared. Carcasses washed up all along the coast; it was suspected that malnourishment and disease were the primary causes. 

Since 2004 researchers from Baja California to the Pacific Northwest have reported unusually high numbers of “skinny” whales. As of 2008, according to whale researcher John Calambokidis, their numbers are now around 17,000.

Some attribute the scarcity of food to the shrinkage of the north polar ice sheets whose undersides would ordinarily grow “carpets” of tiny marine plants (algae) which die off and rain down as organic nutrients onto the muddy seafloor.  Algae is vital food for the tiny crustaceans on which the gray whales forage. The loss of algae has, in turn, altered the gray whale’s food supply.

With the disappearance of their customary food, gray whales are attempting to adapt their foraging habits to the food that is still available. Some will be more successful than others. But one thing is certain: the ocean climate is changing and all marine creatures will be affected.  Now is the time to think about what you individually can do to minimize global climate change.

Experience gray whales by land or by sea, from January (southbound) through May (northbound).

 

VESSEL-BASED NATURALIST-LED DAY CRUISES:

The Farallones Marine Sanctuary Association 415/ 561-6625 ext. 300

 

LAND-BASED:

* SONOMA COUNTY:

Fort Ross State Historic Park, Sonoma Coast State Beach, Bodega Head

* MARIN COUNTY:

Point Reyes National Seashore: from Chimney Rock to Tomales Point *

*SAN FRANCISCO COUNTY: 

Fort Funston

* SAN MATEO COUNTY:

Gray Whale Cove/Devil's Slide, Montara State Beach, Half Moon Bay State Beach, San Gregorio State Beach, Pebble Beach/Bean Hollow, Pigeon Point Lighthouse, Ano Nuevo State Reserve *

* These have seasonal access restrictions; call before you go:

• Point Reyes National Seashore 415/ 464-5100
• Ano Nuevo: 650-879-0227

 

 

Migration map courtesy of Washington State Department of Ecology