San Diego Audubon Society will host more than 100 SDG&E and Sempra Energy employees and their families at this annual volunteer event 9 a.m. to noon Saturday, March 23 at Mariner’s Point, Mission Bay with the primary goal of restoring habitat for the endangered California Least Tern. Up from only 700 nesting pairs in 1970, the species is rebounding but still fragile. San Diego County is home to upwards of 60 percent of the entire nesting population, so protecting the remaining nest sites is vital to ensuring the species’ continued survival. As nesting season for the critically endangered California Least Tern draws near in mid-April, employees and family members from Team Sempra/SDG&E will join San Diego Audubon Society to restore habitat for these important bird species. Every year, San Diego Audubon volunteers donate over 2,000 hours to remove invasive weeds and make these sites tern-ready before the birds arrive to breed in mid-April.