
What’s wrong with this rockfish?
I know, you expected it to look more like this:

Yet it has bulging eyes and a balloon coming out of its mouth! The rockfish above has suffered from barotrauma, also known as “pressure shock.” When fish caught in deep water are brought to the surface, the reduction in pressure causes their swim bladder to expand, pushing out the stomach and eyes.
Rockfish are especially prone to barotrauma, as I saw today on my cruise after we did an otter trawl (dragging a large net through the water column). We had piles of overly inflated rockfish:

Fish can survive from barotrauma if they’re sent back down to recompress, but they’re more likely to die from their injuries the more time they spend at the surface.
Sea hares aren’t found at such great depths, so we didn’t see any today, but we did catch a sea mouse:

And they might just be my second-favorite marine “rodents.”
~Adlysia
*The sea mouse we actually caught was covered in sediment and looked nothing like a mouse.