Some friends were in Santa Cruz (CA) recently when they came across this fish laying along the shoreline. And that’s when I got a text message:
“Excuse me, Dr. Webber [insert sarcastic tone here]. What kind of big-ass headless dead fish is this?”
After what must now be at least several minutes of research (wink), I am at a loss.
Okay, it’s been a while since I’ve taught an ichthyology class, so my ID skills are a little rusty. But I was off to try and help my buddies at least narrow down the alternatives. There were some (what I thought were) obvious things to help:
1) Heterocercal caudal fin
2) Two dorsal fins wayyyy back on the body
3) Scales look more placoid (than ctenoid)
4) Prominent lateral line
These all pointed to some type of shark. Check out the basic layout of a nurse shark, for example:
But then I took a look at this second picture.
The pectoral fins are all floppy and not very shark-like. Shark fins tend to be more rigid; more like oars. Compare the pectoral fins of the nurse shark (above) to a fish like a giant sea bass:
The pectoral fins could just be deteriorated, so that’s not a deal-breaker. But the pelvic fins look like they’re also set way further back than a nurse shark’s, right next to the anal fin (again compare the Santa Cruz fish to the nurse shark picture).
I joked earlier about spending a few minutes on figuring out this “big-ass headless fish,” but it’s turned into a micro-obsession. I’ve emailed a student from my former fish biology lab, asked a marine science buddy of mine, and showed the pictures to a colleague who teaches zoology. Not one was able to able to give a positive ID. The closest we’ve come to is some sort of ratfish (Subclass: Holocephali). But the species found in California coastal waters is the spotted ratfish (Hydrolagus colliei)… and I’m 99% sure it isn’t this:
Help? My next options are to contact a Fish and Game warden from the Santa Cruz area, or possibly the man who, literally, wrote the book on ichthyology (and a former grad school advisor), Peter Moyle. But that would involve a level of admission of defeat that I’m not sure I’m not quite ready for just yet.