Caspian and Elegant Terns join Least Terns to nest at Alameda Point

Naval Air Station-Alameda gained notoriety as a refuge for the endangered California Least Tern when the base closed in 1997.  Over 500 acres were dedicated to protecting the terns’ adopted nesting site next to a runway formerly used by jet aircraft. 

This unlikely bird habitat for the Least Terns some 400 miles north of their historic breeding grounds along the southern California coast offered the birds something they had lost, which drove them to the brink of extinction – nesting sites free of human disturbance near a source of small fish to feed their chicks. 

Surprisingly, two other tern species have recently begun nesting in the vicinity.  Elegant and Caspian Terns seem to be thriving there, while the endangered Least Terns are struggling.

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Alameda Point harbor seals attract educational groups

About 240 students from Eldorado Middle School in Concord visited Alameda Point to make observations of the harbor seals on March 22.  The school participates in an educational program sponsored by the Marine Mammal Center in Sausalito called Ocean Ambassadors. 

The students arrived in two groups.  While the first group was at the trailside viewing site, a second group was on a ferry ride around San Francisco Bay to view marine wildlife. The second group arrived in the afternoon, while the first group went on the ferry excursion.

Alameda Point was chosen for viewing harbor seals because it is the only place on the Bay that is easily accessible for viewing seals.

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Guns and Traps Used to Protect Least Terns at Alameda Point

The endangered California least terns that nest on the old airfield at Alameda Point are well protected during their April to August nesting season.  Fencing keeps people away from the 10-acre sandy nesting site, but it won’t stop other birds and mammals from getting to the eggs and the helpless chicks.  Only a well-armed and outfitted predator management officer can effectively deter other animals.

Every year, the U.S. Fish and Wildlife Service hires a wildlife biologist from Wildlife Services, a division of the U.S. Department of Agriculture.  Typically used for protecting crops and livestock, the agency is also hired to protect dozens of endangered species every year.  The most recent field report available for Alameda Point is for 2019, obtained through the Freedom of Information Act.

The report describes a variety of methods used to deter or eliminate threats to the nesting terns.  First, loud noises and bright flashes of light are fired from a gun to frighten away an avian predator, called hazing.  Second, the wildlife biologist drives a vehicle toward an avian predator, another form of hazing.  Third, predators are trapped.  And fourth, as a last resort, the biologist is left with no other choice than shooting the predator with a shotgun or rifle or euthanizing. 

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New generation of Great Blue Herons born in cypress rookery

The cypress trees in the wetland near the proposed DePave Park at Alameda Point have served as a safe and secure nesting site for Great Blue Herons for many years.  This year is no exception, despite the trees having died and barely standing.  On May 7, Audubon Society bird observer Dawn Lemoine counted 13 juveniles in the nests.

The wetland around the cypress trees provides the ideal landing spot for the young herons’ first flight and subsequent adaptation to life outside the nest.  They can be seen for the first week or so after leaving the nest hanging out in the wetland preening and sunning themselves. Continue reading “New generation of Great Blue Herons born in cypress rookery”

Bay pipefish indicates eelgrass in Alameda Point harbor

A Snowy Egret caught two Bay pipefish in quick succession along the shoreline next to the Hornet Soccer Field on Sunday, November 24.  This sighting of the Snowy Egret catching a pipefish is evidence that eelgrass, a special status marine vegetation, is present in the harbor east of the ferry maintenance facility.  Pipefish “do not wander far from the eelgrass bed where they were born,” according to Bay Nature magazine.  Eelgrass is pipefish habitat, in part, because pipefish are able to avoid predators as their slender bodies blend in with the narrow blades of eelgrass. Continue reading “Bay pipefish indicates eelgrass in Alameda Point harbor”

Great Egret stalks a lizard

Great Egrets are commonly seen wading along a shoreline, in marshes and wetlands waiting for fish to come near before catching them with a quick thrust of its bill.

Great Egrets primarily eat small fish.  However, their diet can also include reptiles such as lizards, amphibians, birds, small mammals, shrimp, worms, dragonflies, beetles, water bugs, and grasshoppers.

This particular Great Egret decided to stroll into the old campground at Alameda Point in search of food.  It walked slowly up to a Rosemary bush and stood there for about five minutes, occasionally making slight head movements, before plunging its head into the bush to catch a lizard.

After holding the lizard in its bill for a few minutes, it gulped down the lizard and proceeded very slowly to another bush.

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