That’s it exactly. Its feathers weren’t ruffled or anything, like it had been attacked, and it was still very much alive. Just clearly not happy about being so.
Many years ago, when I was a youngster, sometime around the release of Jaws, I picked up a one-off pulp magazine at a local store that featured pictures and stories of fabulous sea creatures. It was mainly shark centric and had some pictures and stories of the newly discovered megamouth sharks and speculations about megaladons. One article that stood out was a true eyewitness account from an experienced sailor who was sailing in the bahamas (maybe the bermuda triangle?), IIRC, and had set anchor with his sailboat in some shallows and observed a sea serpent or snake like creature that was very unusual looking circling his boat for some time. I don’t remember the exact details, but the drawings that were made based on his description and detailed in the magazine came back to me almost immediately upon seeing your picture. The illustrations featured a snake or eel like creature with a bony hood or frill very much like your mystery skeleton.
I still have the magazine somewhere and am trying to locate it and the article. If and when I find it, I will try to relate the details.
That would be very cool; thank you. 
I looked up sea robins after reading this, and the skeleton didn’t seem to fit the images I saw. But I’ve never seen one in real life, so I’m not going to dismiss it, either. That would be neat, though, to hear a fish “bark”!
It’s worse when they “grunt”. Icthy is often times very vocal, somewhat disconcerting as a fisherman.
My sister can top most people: she found the remains of a blockade runner from the Civil War. Unfortunately lots of other people found it the same afternoon. (The erosion and tides after a really big storm revealed it last winter; it’s believed to be “The Ivanhoe”, a schooner that beached and burned around the time Mobile was bottled.) It’s still there but now it was covered back up after a few days (and, unfortunately, a lot of souvenir hunters. (Even though it’s on state property an archaeological dig would be way too expensive and difficult, especially when there’s probably nothing of real or historical value other than some spikes and nails; turns out it gets briefly exposed every so many years.)
I’ve found a couple of crucifix bones (the skull of the Arridae catfish) over the years and a bottle with Asian writing (no idea if it floated from Asia or was dropped earlier in the day by a Japanese tourist; no message inside). When I was a kid my family and I were in the Gulf during sand-dollar mating (or spawning) season and came home with a cardboard box full of the things (had to be bleached but my mother and sister used them in crafts for years).
While visiting Sweden as a lad, I found a lava rock about the size of my fist that had washed ashore. Not sure where from. I still have it. It floats!
The northshore of Long Island has a lot of horseshoe crabs and regular crabs, though the ones that are on shore tend not to be alive anymore. I hear there are a lot of sea turtles too, but I’ve never encountered them. There’s some driftwood too. When I lived in Oregon you could find sand dollars everywhere.
I found twenty golf balls on a beach once. That’s all I’ve got.
A phosphorous grenade.
Seriously.
We proceeded to play football with it.
Seriously.
Shells, sand dollars, starfish, jellyfish, driftwood, crabs, and amber.
I’ve been visiting the Washington coast since the 70s and have never had the luck to find one of the Japanese glass net floats. Those things are awesome, but no longer used, unfortunately.
I found hundreds of tiny, bleached sand dollars washed up on shore on St. George Island, FL. Most were smaller than a dime and a lot of them were not much bigger around than a BB. I still have a bunch of them.
Took a picture of a few of them just now: tiny sand dollars
