Surfacing for air and sun I suppose!
This guy was hangin out on some milkweed with a milkweed bug. Didnt appear to be eating the milkweed though.
Caught this little guy in a cup to get a closer look at him, bad pictures, I know...
Larger than most I've seen at ~3mm, certainly caught my eye from about 15 feet away in a pile of stones.
Dont know the exact species of crayfish, maybe someone with more experience can shed some light by the location and picture?
There were hundreds of these all over a fallen tree trunk.