Unusual happening at anchor in St Croix

We've had many critters around the boat when swinging at anchor such as dolphins, stingrays, squid, the rabid crab in St Martin, remora and other variety of fish, but today was our first horse.

Earlier we heard a truck horn and we had to quickly look outside to see if we'd come loose from our mooring and were now up against the road... No, it was just a very loud horn which also freaked out the cats, but happily we were still in our spot.

So, now I hear another strange sound... Sounds like a horse doing a strange, labored nicker-type of noise... Can't be a horse so maybe it is someone having problems with his dinghy motor?  puh puh puh puh... puh puh puh puh... puh puh puh puh...

I just had to get up from what I was working on and look out... To my surprise, this is what I saw...

(Click photo to enlarge)

Bizarre!