Ask any Long Beach dog person about parks, and odds are Rosie’s will come up pretty quickly in the conversation. This dog beach is L.A. County’s go-to spot for off-leash chilling in the sand.

For humans, dog parks are like miniature town greens — except muddy and smelly — where people can go to gossip, swap dog care tips and enjoy the camaraderie of like-minded folks who are not ...