SHERMAN OAKS, Calif.—State Sen. Henry Stern today officially announced his candidacy for the Third District seat on the Los Angeles County Board of Supervisors being vacated by Sheila Kuehl. Standing at the corner of Ventura Boulevard and Stern Avenue in Sherman Oaks—with the Stern Avenue street sign serving as a backdrop—the lawmaker announced on Zoom, “I’m running.” Stern said he waited until after the recently redrawn supervisorial districts were approved before announcing his run, saying, “I didn’t want to declare for this office not knowing who I’d be working to represent. That didn’t feel right.” He indicated that, if elected, he would focus on quality-of-life issues in LA County—saying, “You may not even know who your county supervisor is, but you do know that something’s not working right in LA.” Stern—a Senate Democrat who is seeking what is officially a nonpartisan seat on the five-member Board of Supervisors—joins a field …