I was checking on the Purple Marin house at the base of 11th Street (just east of Col Sam Smith Park) this evening and found at least 6 birds at that martin house. A I was leaving I heard a Red-necked Grebe call on the lake, so I went back to look. There are the 3 nesting pairs in the park, but I was surprised to hear one on the lake. Scanning for the grebe, I found it along with two Horned Grebes, about 100 metres from shore.
There are 2 more martin houses visible on the east side of Rotary Park (1 block east), but I didn't see any action there.
BB