Warning signs have been posted at the mouth of the Ventura River to protect a small flock of least terns, an endangered bird temporarily in the area.
The signs, warning that harassing the birds is a federal offense, were posted after passersby complained that people were riding bikes, throwing stones and flying kites in the Ventura River estuary where the adult least terns are teaching their young how to hunt for food, said Barbara Fosbrink, Ventura city parks department spokeswoman.
The birds need to be left alone when they are in the training process because they are very vulnerable. “The birds are at a very sensitive stage when they are feeding,” said Mark Capelli, a California Coastal Commission biologist.
The adult least terns frequent the estuary for its warm, shallow waters and excellent food resources, but this is the first time they have brought their young with them, Fosbrink said.
The birds are naturally restricted to Southern California’s sandy beaches but their habitat is slowly diminishing. “There are fewer and fewer places for them to go. Most beach property has been developed and their feeding ground is either populated or polluted,” Capelli said.
The birds once numbered in the thousands, with nests from San Diego to San Francisco, but numbers dwindled to 300 pairs by the early 1970s. No figures on their current population were available.
The flock of about 20 probably came from the Santa Clara River mouth west of Oxnard, where the birds normally nest.