In September every year, California least terns migrate from San Diego to Central and South America after nesting along the coast during the summer. When they depart, scientists from San Diego Audubon collect data to assess how their hand-management restoration efforts have affected vegetation and land cover in the nesting sites. San Diego Audubon has been collecting data from the least tern’s nesting sites for more than six years to improve the nesting sites and increase the population of the bird species. Their goal is to remove the non-native plants and preserve the native plants. They want to make sure that the birds have free spots with sand to nest on. “We want to improve the nesting areas of the California least terns. Our goal is that there will only be native plants and only 20 percent vegetation cover,” said Megan Flaherty, who is restoration program manager at San Diego Audubon. The California least terns are coastal species, which means they spend most of their lives out at sea fishing. From April to September, they are nesting on the coastal sand dunes in California and Mexico. “We have to protect them because they are an important part of the coastal ecosystem,” said Flaherty. San Diego Audubon checks on the nesting sites two times a year to see how their hand-management work is going. In spring, before the birds get to the nesting sites, and in fall, after the birds leave the nesting sites. “The problem is that islands in Mission Bay are manmade, which means that there is a lot more vegetation and a lot more non-native plants,” said Flaherty. Scientific data collection helps San Diego Audubon, San Diego Association of Governments, and the City of San Diego in maintaining nesting sites of the least terns.
Throughout the year, San Diego Audubon leads a number of habitat restoration efforts around Mission Bay that support endangered species.