Boobies Have Arrived On the Channel Islands

Posted by: Sandy Steinman | April 1, 2022

Boobies Have Arrived On the Channel Islands

from the Santa Cruz Island Foundation

Boobies, possibly named from the Spanish slang ‘bobo’, meaning stupid, historically had a habit of landing on board sailing ships, where they were easily captured and eaten. Now, global warming is bringing these primarily tropical and sub-tropical birds northward into new territory. Five of six species have been spotted by birders at the California Channel Islands, and two of them have taken up residence. Sightings of Masked, Red-footed and Nazca boobies have been noted, and both Brown and Blue-footed boobies have now settled in to nest.

Brown Boobies (Sula leucogaster) are large seabirds with 5-foot wingspans. They are easily recognized with their dark chocolate-brown upper-parts starkly contrasting with their pure white bellies. Like all Boobies, they have webbing connecting their four toes. They were first sighted nesting at Sutil Island, off the southwest quarter of Santa Barbara Island, in 2017. Sutil is about ten acres in size, and rises to a heigh of 301 feet.

Prior to 2017, Brown Boobies had been observed at the Channel Islands only 16 times in the 30 years between 1984 and 2014. They were first seen roosting in small numbers on Anacapa and Santa Barbara Islands in 2013.

There was a dramatic rise in their numbers in 2015 with more than 170 individuals observed at Santa Barbara Island. In 2017 four nests and 102 individual birds were counted on Sutil, and since that time, they have nested on Sutil annually. Prior to this, the closest breeding colony was located on Islas Coronados off Northern Baja California, Mexico.

Blue-footed Boobies (Sula nebouxii), the clowns of the Booby world, have long captivated observers with their comical mating rituals, “twigging” and blue-footed dance routines. They will sit on just about any object near or above the water, and often show no fear of people. This species has long established breeding and nesting grounds on islands in the Sea of Cortez. According to ornithologist, Paul Collins, “an unprecedented invasion of this species to coastal areas in southern California occurred beginning in fall 2013 with small numbers reaching a number of the Channel Islands, and with a few individuals remaining for extended periods into fall 2014.”

On Sutil Island in 2020, a Blue-footed Booby paired with a Brown Booby and produced a hybrid fledgling! Last year a pair of Blue-footed Boobies nested and successfully fledged one young in 2021. This is the first confirmed breeding record for Blue-footed Boobies in the United States and the first for the California Channel Islands.

With special thanks to ornithologist, Paul Collins, for sharing his unpublished Booby data.

Posted in Birds | Tags: Boobies, Channel Islands

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