2012 Brings Record Number of Gray Whale Calves

2012 Brings Record Number of Gray Whale Calves

calf and cow

Summer 2012

A record number of gray whale calves have made their first seasonal journey up the West Coast. Traveling from their nursery lagoons in Mexico to their summer feeding grounds in the Arctic, the number of gray whales from the Eastern North Pacific population is nearly double the number born in previous years. According to Jorge Urban and his colleagues at Universidad Autónoma de Baja California Sur, a record 1,198 gray whale calves were born this season along the coast of Baja California, where the animals spend the winter breeding and calving. In comparison, 599 whales were born in 2011, and 183 in 2010. The newborns will soon grow up to 15 meters in length and weigh up to 36 tons. Over the course of their 50 to 70 year life span, the whales will travel 15,000 to 20,000 kilometers annually. This year’s births contribute to a recovered gray whale population, thanks in large part to protections under the U.S. Marine Mammal Protection Act and Endangered Species Act.

Scientists from NOAA’s Southwest Fisheries Science Center conduct annual counts of northbound gray whale calves as they move into U.S. waters and pass the Piedras Blancas Light Station, near San Simeon, California. This year’s final counts documented 330 newborns making their way past the counting station with their mothers. NOAA scientists will continue to monitor the calves from this year’s record crop as they head toward Oregon, Washington, and Alaska. Calf counts from this station provide the most reliable estimates of northbound calves, and historical count records indicate that the reproductive success of the Eastern North Pacific population is highly variable. NOAA scientists cite evidence that the variation is linked to the distribution of seasonal ice in the Arctic, which affects the whales’ summer feeding patterns.

Whaling in the 1800s and early 1900s severely depleted the Eastern North Pacific population of gray whales. A ban on international whaling in the 1930s was the first step to protecting the imperiled species. By 1972, the Marine Mammal Protection Act advanced these protections by prohibiting actions that harmed or harassed – i.e., “take” – gray whales in U.S. waters. In 1973, the Eastern North Pacific stock of gray whales was listed as endangered under the Endangered Species Act. By 1994, the population had recovered to near its estimated original population size and was delisted that same year. Today, approximately 19,000 gray whales, including this year’s newborns, migrate along the Pacific Coast, from Mexico’s Baja California peninsula to Alaska’s arctic waters.

This year marks the 40th anniversary of the Marine Mammal Protection Act. NOAA Fisheries, along with the U.S. Fish and Wildlife Service, administers this and other laws to protect animals, like the Eastern North Pacific gray whale, and their habitat. As we watch hundreds of newborn calves swim alongside their mothers during their first seasonal migration, it is fitting to reflect on the success of the Marine Mammal Protection Act – and how it helped ensure that the gray whale continues its epic journey to distant waters, steering clear of the brink of extinction faced in the not-so-distant past.

To follow the newborn’s first seasonal migration and to learn more about gray whales please visit:

Gray whale calf count 2012

Gray whale research 

Cetacean Health and Life History Program 

Gray whale population studies