As many are aware, iNaturalist is not only a great resource for animals, plants, fungi, and other non-human life, it's an awesome way to meet other nature nerds, and I had the pleasure of birding at four different spots around San Francisco by with Liam O'Brien ( @robberfly ) and Donna Pomeroy ( @dpom ), both folks who I've met through iNaturalist. Liam and I relied on Donna's bird expertise to find two lifers, Barrow's Goldeneye and Cackling Goose (in this case an Aleutian Cackling Goose), and saw some amazing raptor action at Arrowhead Marsh, where two Peregrine Falcons and a Northern Harrier were hunting. One Peregrine was successful, hopefully Donna and Liam got some decent pictures of the whole thing. Here are Donna and Liam at Oakland's Middle Harbor Shoreline Park.

The impetus for this trek around the bay was the East Bay iNaturalist Happy Hour organized by Ken-ichi Ueda ( @kueda ). Discussing awesomely nerdy topics, such as gulls vs galls, over some beers, was a lot of fun, and I am guessing is unprecedented in a bar setting.
If you'd like to organize an iNat Happy Hour in your area, go for it!

Back row from left to right: @constance, @robberfly, @tiwane, @danielled83, @sea-kangaroo, @kueda. Front row from left to right: @dpom and @folini.
Other iNatters came after this photo was taken, so feel free to add them in the comments.