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Diving Bird Arrives for Winter

Mia Davidson, Jan Sattler

Mia Davidson, Jan Sattler

In addition to the winter migrants willets and sandpipers, the eared grebes (Podicep nigricollis) have arrived to Laguna. Being the most abundant species of grebe, the smallish bird averages 12 inches in size, has a small dark bill and red eyes.   When it is seen locally, it displays its winter plumage with a dark gray upper body and lighter colored undersides, face and throat.  The winter coloring is distinguished from its summer plumage where the head and neck are almost black, the undersides become a vibrant reddish-brown and with golden tufts at its ears.

Instead of webbed feet, the eared grebe has lobed toes with flat nails, short pointed wings and black legs that are set far back on its body making walking on land ungainly.  Possibly as a consequence of this, the bird is not considered a strong flyer and spends very little time on land. In fact, it is almost entirely aquatic and can only take-off and land on water. Its diet is primarily made up of small aquatic invertebrates such as crustaceans, larvae, brine shrimp as well as insects and a few small fish. The grebe is a superb swimmer, quickly diving from the surface of the water and using its feet like twin propellers to dart around near the sea floor for extended periods of time. It has a maximum lifespan of 12 years. Fossil records indicate that the grebe is possibly the earliest known diving bird and is unique in that it has no obvious close evolutionary relatives.

In mid-August to late November, flying only at night, the eared grebe migrates to its winter grounds on the Pacific Coast and Mexico. They usually are late arrivals because they stop over at alkaline lakes such as Mono Lake and the Salton Sea where they rest and double their weight for the continued migration. Along with fat deposits and digestive organ growth, the chest muscles shrink so that they become incapable of flying.  In fact, the eared grebe cannot fly for nine to 10 months of the year, which is the longest amount of time for any bird capable of flight. When preparing to depart, further physiological changes occur with the strengthening of the chest muscles and the contraction of the digestive organs. This cycle repeats several times each year as it travels from habitat to habitat.

The eared grebe will remain on the Pacific coast until March when again migrating only at night, it will fly to its breeding grounds where they gather in large, dense colonies on shallow, marshy lakes in the western U.S. and Canada.  After an elaborate courtship, the mated birds together construct a nest on the waters edge or on floating vegetation in a marsh, incubate three to five eggs and care for the young even allowing them to ride on their backs as they swim.

While nesting, minks, raccoons and coyotes prey on the eared grebe.  When the grebes gather in large flocks at its wintering grounds in Mexico, great blue herons and Western gulls have been observed occasionally attacking them.  Habitat loss from agricultural expansion, urban development, human recreation, environmental contamination and pollution are considered the biggest threats.  To identify an eared grebe in Laguna, look for a small, fluffy, dark grey, duck-like bird floating on the calm ocean.

Residents and ocean swimmers Mia Davidson and artist Jan Sattler are actively involved in protecting Laguna Beach’s coastal resources.

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