Natural La Jolla: Brandt's cormorants now nesting at La Jolla Cove

NATURAL LA JOLLA:

Birding could not be better than at La Jolla Cove right now. If you peek over the edge of the fence on the north side of the lifeguard tower, you'll be able to see a Brandt's cormorant (Phalacrocorax penicillatus) nesting rookery in mid-season. Over the past couple of months, the birds have been staking out their spot and defending it from others. The nests are mounds of dried sticks and grass, perched on the edge of the cliffs above The Cove beach.

Each pair of cormorants will protect the nest site from intruders, but you'll still see a cormorant from time to time stealing a bit of dried grass from a neighbor's nest. A minor squabble ensues and the birds will poke at each other and croak quietly (these birds don't make much noise). Each pair may use the same area for nesting every year. Males will make trips to gather nest material, bringing it back to the female, who will carefully tuck it into the nest and arrange it just the way she wants it. Nest tending takes up a lot of her time.

The birds themselves are in perfect breeding plumage. They have long white very thin feathers at their crown and along their back. Their throats turn a brilliant blue that matches their amazing blue eyes. Here you can see all the displays of the breeding season, which are amusing to watch. Males defend their territory and their nest area, not in an aggressive way, but by their posture. They bend their neck and head back until their head nearly touches their back, extending their blue throat patch, while lifting their wings from their sides and raising their tail. They will then flutter their wings for several seconds before resting and repeating. They also slowly arch their neck forward repeatedly until their beak nearly touches the ground.

Nests may have 3-6 eggs in them, and the parents tend to the eggs by periodically moving them and by changing positions on top of them. Eggs are a delicate blue color, eventually taking on the stain of dried seaweed. Both parents will incubate the eggs, which should be starting to hatch soon. Cormorants feed their young by regurgitating whole fish that they have caught. Around the nest you may see scattered tiny silver fish.

La Jolla Cove presents a unique way to view these wild seabirds and you can see all of this without binoculars. It's a fascinating look into the breeding behavior of a usually distant cliff-dwelling seabird.

Kelly Stewart is a marine biologist with The Ocean Foundation who writes about the flora and fauna of La Jolla. She may be reached at NaturalLaJolla@gmail.com

 

 

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