Seals, (the fury kind).
I was a Company Commander of an Alaskan Native NG Company on the Bering Sea north of Nome.
Use to go out with those guys hunting. All you get is a head shot. If you wound them they sink, hitting in the head you can retrieve them.
Problem is you're hunting from a small boat bouncing around in choppy seas and your quarry is also bobbing around.
Get too close and they dive, get too far away the wind gets you.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071