Crab Megalops

So, I learned a new term this weekend "Megalops".
A larva, in a stage following the zoëa, in the development of most crabs. In this stage the legs and abdominal appendages have appeared, the abdomen is relatively long, and the eyes are large. Also used adjectively. (they forgot to mention it has a freaking stinger like a scorpion.)

The addition of this term to my vernacular was instigated by a little drop of blood. Mine.
I got stabbed by one of these little suckers shortly after catching a coho out at PC on Saturday. It was on my rudder handle and attacked me as I was just minding my own business trying to ensnare myself some ocean meat. After impaling me with it's little pecker, I had to actually pull it out of my finger -  it was kinda freaky with its black little eyeballs staring at me. (was it smiling? - hard to say)

Anyhow, I didn't notice anything adverse to the sting, at least not yet. I also think it came from the coho I caught, her belly was packed full of these little vermin. I guess you learn something new all the time. Next time I'd like to involve less of my own blood.

Ah yes, life history of the crab.  Brings back memories of marine invertebrate zoology.

Some crab larvae and megalops have very long dorsal and rostral spines.   As far as I know they really aren't stingers in that no venom is secreted from them.  It's all about defending against predators like fish.   Evidently, the coho was less bothered by them then you were.

Only one crab has poisonous larvae that we know of to date and they are on the East Coast.  I get stabbed by the spines of megalopas on a daily basis during the summer and there is no lasting affect.

Check out this link it is a cool picture of a smelt that tried to eat a zoea

http://www.nwfsc.noaa.gov/sem/images/surfsmelteatcrb1552c150dmag.jpg

Ha ha, Zoea - your screen name fits my story perfectly. That pic is cool - thanks for the link.


I hoped it wasn't venomous, but wasn't too concerned. Mostly it was just a little odd looking down at my finger seeing these two beady little black eyes staring back at me as I imagine him thinking "I have but one little spine, but I will take you down."

I also caught a coho in PC on Saturday and these little guys came pouring out of its belly when I was cleaning it. They all appeared to be dead, but obviously a big part of the diet this time of year. I wonder if they suck them off the rocks one by one. Anyway, this coho was stuffed full of them

More likely they haven't settle out of the water column yet.  This is the time of year they drift with the currents in search of new territory. How the know when to settle out and latch on to something is still a mystery as far as I know. Alan Shanks (http://pages.uoregon.edu/oimb/Faculty/shanks.html) is the crab larvae guru that I'm most familiar with, as well as being an all around great guy. He post a lot of his work on the internet if you want to read away a few days.

Yeah I agree with Yaktrap, these guys haven't moved to the bottom yet but they are on their way back in from being off the shelf.  They show up on a fortnightly periodicity because they are likely being transported across the shelf on internal waves. I am a graduate student in Alan's lab and focusing my research on Dungeness crab larvae and their movement in the oceans so this is something I probably spend to much time thinking about.

Yeah I agree with Yaktrap, these guys haven't moved to the bottom yet but they are on their way back in from being off the shelf.  They show up on a fortnightly periodicity because they are likely being transported across the shelf on internal waves. I am a graduate student in Alan's lab and focusing my research on Dungeness crab larvae and their movement in the oceans so this is something I probably spend to much time thinking about.

Very interesting guys. Thanks for sharing the info.

Yeah I agree with Yaktrap, these guys haven't moved to the bottom yet but they are on their way back in from being off the shelf.  They show up on a fortnightly periodicity because they are likely being transported across the shelf on internal waves. I am a graduate student in Alan's lab and focusing my research on Dungeness crab larvae and their movement in the oceans so this is something I probably spend to much time thinking about.

Thinking about it while your dropping a line off the kayak, now that sounds like a good life choice! Hey, you could mount enough gear onboard and become a manned drifter/sampler....just a suggestion

Damn, a new genus of Human- Crustaecea Nerdicus         

It always starts with crab jokes and goes downhill fast from there. I'm outta here.

Don't go away mad, honestly i'm kind of envious. While I'm not at all a fan of the crab in any form, to me it's amazing that we have such a great oceanic brain trust here. I might be a bit irreverent, but i actually learned something. Well, actually two somethings. One, while i'd learned from other discussions here that crab have a larval stage, i didn't know one stage was called megalops. Two, i didnt know that there were multiple larval migrations of the course of a year. For all i knew the darn things spent that stage under rocks inshore.

 

Out of curiosity.  I would like to hear some shout outs from my people in the fisheries field and what it is you do specifically.  I collect salmonid smolt migration data on the Snake R.  How about you?

I use to be a marine technician working for a short but enjoyable stink with ZOEA's now advisor, Alan Shanks, and many others. Traveling the world, playing in boats, getting paid to dive and fish. Then I thought it would be a great idea to get too many degrees, now I mostly sit at a computer and write about other people's exciting science in the oceans of the world. I work on everything from marine energy engineering to reviewing fisheries assessment studies. Jack of all ocean sciences, but master of none is probably the best summary of what I do. Who know, maybe next year I'll be reviewing FishPimp's work, somebody has to do it.