In the first video it could be a flying Rod: Check this
Who knows what it could have been, and for the second video your guess
is as good as mine which is I got no idea.
Bullets disintegrate when they hit water. I seen they did a special on Mythbusters whether if bullets would travel thru water when shot. bullets would
go about a foot at most into water and disintegrate. I see this as the same effect bullets hit water disintegrates and what we see is a piece of
shrapnel flying at subsonic speeds deflecting off the water in the foreground. well this at least my two cents. or who knows. .
Wow i re-reviewed the footage and seen what is talked about. yeah that could be a rod I guess or maybe some weird bug.