This post was contributed by a community member. The views expressed here are the author's own.

Health & Fitness

Great Migrations: Grey Whales Reappear off our Coastline

Soon, one of the great wildlife migrations will occur off the California coastline.   The California Grey Whales (Eschirichtius robustus) are appearing off the coast in an annual trek that has an annual round trip of nearly 15,000 miles.  These whales travel each year from the rich summer feeding grounds of the Bering and Chukchi seas along the margin of the Northeast Pacific south to over winter in the warm waters of Baja California.  These whales migrate along the margins of the coastline and can easily be seen spouting in near shore waters along the coast.  Good viewing locations near the San Francisco Bay include Point Reyes and Point Montara.  Grey in coloration, the whales are covered in parasites such as barnacles and whale lice, giving them a blotchy, mottled look up close.  These whales have two blowholes on top of their head, which creates a recognizable V-shaped blow.  Growing to lengths of over 45 feet, the whales are recognizable by the absence of a true dorsal fin.  Instead they have a series of knobs along their backbone leading to a deep notched, almost heart shaped tail, or fluke.  Like the Blue and Humpback whales that visit our waters to feed on krill and small fish during summer months, grey whales are baleen whales.  Baleen whales are filter feeders. Their teeth are adapted as special overlapping combs that filter out the small organisms providing sustenance for the largest animals on the planet.

This baleen from the larger whales was once coveted as a kind of 19th century plastic to make flexible materials like skirt and umbrella stays. Unlike its cousins, Grey Whales are bottom feeders and slide along soft substrates filtering crabs, worms and other invertebrates from the muck.  Like a smoke stream, I have seen plumes of sand and mud behind feeding Grey whales as they scour along the bottom.

Growing as large as forty tons, Grey whales are classified as the only member in their own genus and family. Once distributed in the eastern and western margins of the North Atlantic and North Pacific Oceans, Grey whale populations have been dramatically reduced among their entire range.  The European population is believed to have been extirpated by humans as early as the sixth century.  Whalers hunted a separate population in the Western Atlantic to extinction in the 1800s, and the Pacific population dramatically reduced not long after. A remnant population exists off the coasts of Russia, Japan and Korea now numbering less than 200.

Find out what's happening in Pacificawith free, real-time updates from Patch.

The shallow waters of the lagoons such as San Ignacio and Scammon’s Lagoon have provided refuge for these whales to birth and mate for centuries, until discovered by whalers from New England.  One notable whaler was Charles Scammon, who followed whales into the lagoon named after him and killed hundreds of females in the mid-1800s like shooting fish in a barrel. Although the oil and baleen from Grey whale s were considered inferior to that of Right Whales and other Rorqual whales, they were easier to catch and the diminished numbers of other species made these desirable. After a gestation period of around 13 months, females give birth in the protected southern lagoons.  The toll on the mother whales lead to the deaths of the baby whales, and pressure from other whalers along the coast nearly caused the demise of the entire population.

Scammon was also a naturalist.  In 1874 he wrote a book The Marine Mammals of the North-western Coast of North America, now considered a classic for his early observations.

Find out what's happening in Pacificawith free, real-time updates from Patch.

Following protection under the Marine Mammal Protection Act of 1972, this population has recovered from less than 1000 remaining individuals to around 20,000.

As a young biology student at the University of California, Santa Barbara I participated in a long-term study of Grey Whales in the lagoons of Baja. With members of the American Cetacean Society, we camped along the edge of an old wharf off Guererro Negro Lagoon on an estuary just north of Scammon’s Lagoon.  We identified individuals, observed movements, documented births and mortalities and I even dove in the lagoon to take bottom samples and observe feeding behavior.

A conservation success story, the population of the California Grey Whales has rebounded in my lifetime. 

This winter I will be following the whales south and reporting back on my observations in the former whaling, now whale-watching  lagoons of Baja.

©2013 David McGuire.  Learn more about our work at www.sharkstewards.org

We’ve removed the ability to reply as we work to make improvements. Learn more here

The views expressed in this post are the author's own. Want to post on Patch?