A very crowded log in Delta Ponds. It looks like they are having a log rolling contest. I think all of the turtles are Red-eared Sliders, which seem to be taking the ponds over from the native Pond Turtles.

According to USGS - "The Red-eared Slider's indigenous range broadly covers the midwestern states and extending as far east as West Virginia and a disjunct (relict) population in southern Ohio, as far west as eastern New Mexico, and as far south as south of the Rio Grande River into northeastern Mexico."

Release of pets has caused their increased presence in other areas.