Probably the most recognizable birds in the estuary at Morro Bay are the herons. Of these large wading birds great egrets are most noticeable with their bright white plumage. Once named common egret, the great egret is seen worldwide. There are two other egrets seen in California, the snowy and the cattle egret, both much smaller than their cousin the great. In Florida and the Gulf coast you can find the reddish egret, which is more bluish with reddish breast feathers, and has a white morph.
While the name egret is specific to these birds, scientifically they belong to the heron species along with the great blue heron, green heron, night heron, little blue heron, yellow-crowned heron, tri-colored heron, and the great white heron.
Other wading birds lumped together in this family are bitterns, glossy and white ibis, roseate spoonbills, wood storks and even flamingos.
As you can see all this variety can make for an exciting adventure of discovery depending on what part of the country or world you are in. In the United States coastal areas, the Atlantic, Pacific and the Gulf waters, are the best places to find these birds although some can be found at inland locations. Here on the Central Coast, and particularly in Morro Bay, egrets and herons are easily found.
Of the two egrets common in the estuary the great egret stands out due to its height and coloring. It has a long yellow bill and long black legs. Egrets will search for food in saltwater and fresh marshy areas, streams, lakes, ponds, mud flats, rice fields, and other open fields. It feeds on fish, frogs, snakes, mice, salamanders, crayfish, grasshoppers, moths, crickets, and other aquatic insects. Unlike other herons, the great egret does not feed at night.
Great egrets are all white all year and stand about 37 to 41 inches tall. They have a wingspan of approximately 55 inches. In flight they extend their long black legs straight back and have a deeply bowed neck. During breeding season from February through July they grow a long, graceful cape of filmy plumes. It was these plumes that almost drove the species to extinction by 1900. The feathers were highly prized for adornments on women’s hats. Largely thanks to protection efforts by the National Audubon Society the practice was stopped, and the birds recovered.
These birds nest and roost in large rookeries in trees. Many of them used to nest along with great blue herons in the eucalyptus and Monterey cypress trees located between the Inn at Morro Bay and the Natural History Museum. During the 1980s and into the 1990s double crested cormorants began nesting there and the caustic guano from these birds caused a die-off of the trees. Only a few egrets attempt nesting at this site now. They lay three to four pale blue-green eggs in the nest and young are hatched from 23 to 24 days after laying. The young take flight in 42 days and must find their own hunting territory away from the parents.
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