European Paper Wasp, Polistes dominula ("little mistress"). An exotic invader, introduced in 1968, now widespread. Unlike our native Polistes aurifer ("gold-bearing"), which is found near ponds with native vegetation, this Vespid is found in the baylands where the environment is artificial and highly disturbed. 99% of plants and a number of the insects there are exotic.

The hooked tarsi may be male-specific. At this time of year only males and a few overwintering females (foundresses) are likely to be found, per Wikipedia. This Vespid also gets into attics in the Bay Area where it builds huge nests.

Right after this shot was made, this wasp succumbed to the snares of a Black Widow Spider; pix of that event posted separately.