Friday, March 2, 2012

Why is this turtle so unhappy?

loggerhead sea turtle: "AHHHH!"

Could it be because:

(A) it is being accosted by a man in a speedo?

(B) it just realized it had been swimming east this whole time instead of west and was now off the coast of Spain, not Mexico? or

(C) it has an uncomfortable crab companion near its bum?

If you guessed (A) or (B), you obviously missed that this blog is about crabs. If you guessed (C), you're correct and have picked this Crabday's featured crab!

Sargassum Crab
Planes minutus

a sweet little sargassum crab

(not to be confused with the sargassum swimming crab, Portunis sayi)

"Hey! I'm swimmin' here!" - P. sayi

The sargassum crab, also known as the Columbus crab or gulfweed crab, is found on flotsam in the ocean. The most notable "flotsam" of all is the Sargasso Sea, and wouldn't you know it, the sargassum crab thrives there, floating among the Sargassum mats.

a minute P. minutus sayi mama! (found here)
(Thanks, Joe, for the species correction!)

When not living in masses of floating debris, P. minutus finds a home on loggerhead sea turtles, eating other epibionts like barnacles and parasitic amphipods! Unfortunately, the crabs seems to pick a not-so-cozy-for-the-turtles spot to call home:

peek a boo!

That's right, not one, but two sargassum crabs!
You can see the claw of the 2nd crab next to the 1st.

That's one tight squeeze! If I were these guys, I think I'd be looking out for the nearest Sargassum patch! (As for the sea turtle, I guess these crabs are found on a lot of them, so this turtle probably really was just upset about the speedo.)


  1. Love your blog! Here's a link to some amazing looking crab found in the S.Pacific:

  2. That is an amazing looking crab! What a neat island in the South Pacific - thanks for the link!

  3. This picture has been haunting me. Did they remove the crabs?

  4. You crack me up Torrie! Yes, they removed the crabs because they thought the crabs were keeping the turtle from diving down (they thought the crabs would pinch the turtle's behind if it got too deep), but there have been numerous sightings of crabs on these sea turtles so I'm not sure how much it actually bothers them.

  5. Hello Molly, I just came across your post. I am a PhD student at the University of Florida and I am studying Planes crabs for my dissertation. Your pictures are great. Can you tell me who is leading these expeditions? Miguel Angel Rodriguez? My email address is Many thanks!
    p.s. The picture of the little egg-carrying female is a swimming crab (Portunus sayi), not a Planes. You can tell by the claws and the paddle shaped last walking leg.

  6. Thanks Joe! I see the swimming legs now! Woops.
    The most recent expeditions that I've seen were led by the Monterey Bay Aquarium Institute and maybe also the Pew Environmental Group to look at the Sargasso Sea. I don't believe Miguel Rodriguez was affiliated with any research - I think he was just out with his buddies, saw the turtle, and picked it up! (I can't find the original website where I got his pictures, and it was in Spanish, so I'm going off of memory of roughly translated explanations.)
    I hope this helps, and good luck with your dissertation!