It’s time to hang 20 — the fourth annual Surf Dog Surf-A-Thon will take place in Del Mar on Sunday, September 13, to benefit Helen Woodward Animal Center. In addition to the canine surfing competition, this year’s event will also feature the first Doo the Dah for the Dogs contest, in which individuals and teams of up to ten people will surf while wearing themed costumes. Judges include world champion tandem surfer Guy Takayama and members of Swami’s Surfing Association. In the Beach Bum and Bikini Babe Canine Costume Contest, dogs will strut their stuff while celebrity judges pick the best costumes. (858/756-4117, ext. 339, www.animalcenter.org)   Mia Stefanko