First try your "interest" groups from Fresno, then try the
Alameda Seniors Mastick Center to browse and sign-up for exercise/computers/art/discussion groups. Also on Bay Farm Island there are various club associations along with your HOA.
Interested in locating property to buy? I can help you, having lived here for several decades. Cell 510.289.3737. Jennie Wong, BHG Realtor www.bhghome.com/JennieWong/mylinks/aspx