The annual tours to the least tern colony at Alameda Point were sold out again this year. Three groups totaling about 100 people listened to a presentation about the endangered birds before boarding a bus at the Crab Cove Visitors’ Center.
It is the only time that the general public is permitted to enter the federally owned former aircraft runway area to view the terns nesting. Guests are not allowed to leave the bus.
This once-a-year glimpse of Alameda’s colony, managed by the U.S. Fish and Wildlife Service (USFWS), is very different from the daily opportunities to view the Huntington State Beach least tern colony near Los Angeles, managed by the California Department of Parks and Recreation.
The 9.6-acre Alameda Point least tern nesting site has a 500-acre buffer zone. During the nesting season, volunteers monitor and record tern behavior and threats from predators, such as hawks and falcons, while sitting in their vehicles.
The 13-acre Huntington State Beach Least Tern Natural Preserve is protected by a 15-foot buffer zone on three sides. The Huntington Beach Bike Trail hugs the fourth side of the colony, with the busy Pacific Coast Highway only 40 feet away.
At Huntington State Beach, docents amble around to educate visitors about natural history and conservation while recording observations about predators. Over the recent Memorial Day weekend at Huntington Beach, people casting fishing lines into the ocean, throwing Frisbees, and laying on blankets were often not more than 30 feet from adult least terns loafing and sometimes mating on the beach.
During the non-nesting season in Alameda, volunteers remove weeds by hand, and pick up terracotta tiles, wooden A-frames, and oyster shells used for sheltering the chicks, and then re-distribute them in April before the terns arrive. USFWS sprays an herbicide before the terns arrive to minimize vegetation that sprouts up on the bed of imported sand. This is to help to maintain the look of a beach with good sight lines preferred by terns.
At the Huntington Beach Preserve, the state park department stopped using shelters. They, too, use an herbicide, but only for grasses. The low-growing flowering vegetation on this natural beach is allowed to remain and serves as camouflage for nesting adults and for the chicks when they hatch.
At Huntington Beach, certified volunteers count the nests, eggs and chicks twice a week. They walk through the site inside of sand-colored canvas blinds held together with PVC pipe that they carry. At Alameda Point, the wildlife biologist does not employ the use of a blind.
The Huntington State Beach Least Tern Natural Preserve was established in 1973 as the first fully protected tern colony in California. This preserve implemented the central tenet of the USFWS-approved recovery plan for the least tern by providing a well-defined nesting site that is secure from casual disturbance, primarily by human recreational activity often accompanied by canine companions. The wisdom of this practice is illustrated at Alameda Point: No least terns have ever nested outside of their fence.
The two other determining factors in the breeding success of the terns are the presence of small fish in nearby waters, which can vary due to climate and current, and the presence of predators, which can vary by location. No scientific formula exists to prescribe how far away human activity must be for successful nesting of the terns.
This year, as of June 20, there were 500 nests at the Huntington Beach Preserve. Alameda Point had a count of 315. There are 27 sites in California that had 10 or more nesting pairs in 2014. Both Alameda Point and Huntington Beach typically rank in the top five. Huntington Beach least tern nesting news updates are posted on the Sea and Sage Audubon Society website. There are no published news updates or progress reports about Alameda Point least tern nesting activity.
The annual Alameda Point “Return of the Terns” tours happen every June.
Originally published in the Alameda Sun.
Huntington Beach photo gallery