Posted by: Alison Cawood | August 7, 2009

Crabs and Fish Eggs

Here are some more pics of the piece of plastic grating that was collected off the side of the New Horizon yesterday.   The best guess is that the eggs are from a flying fish.

Plastic-crab-ruler-8-6-09On Thursday, Aug. 6, as SEAPLEX scientists continue towards the North
Pacific Ocean Gyre
, a large piece of plastic with crabs and fish larvae
was retrieved from the water using a hand net.

Fishlarvae-8-6-09Close up of fish larvae were found growing on the large piece of plastic
with the crabs.


  1. when the larvae grows, will the fish eggs have any problems with them??

    -CHVS student

    • The larvae will hatch out of their eggs and become part of the zooplankton (where they will be carried around by winds and currents) until they grow large enough to swim against the currents.

  2. Wow! What an amazing photo! How sad, though, to see marine life using a piece of plastic as part of their natural habitat. I am kind of surprised to see the crab and eggs being able to attach to plastic. I would have thought it would be too slippery.

    • These organisms would attach to anything floating around. The natural floating objects are not incredibly common, so they are likely to attach to anything that comes by. After the plastic has been in the ocean for a while, it is covered with microbes, so unless the plastic itself is toxic, it should be an acceptable habitat as far as the organisms are concerned.

      • Thank you Alison for answering my question. I am learning so much by following you on your SEAPLEX adventure.

        Wishing you a safe and successful voyage.

  3. I cultured Amazonas Fishes some time ago in an Aquarium and the Fishes placed their eggs also on Plastic.

    Really great Photo with the larvae!

  4. All of that life going on, on a tiny object floating way out at sea. Amazing. What a little “Hermit” crab doing out there? It must have been floating since that debris was on the shore.

    Are we there yet? When the heck are you rolling up on the plastic mass?

    • That isn’t a hermit crab, it is a pelagic crab. They live in open water (not associated with the coast) and are most often found resting items such as driftwood, seaweed, or organisms such as jellyfish.

      Assuming that the weather holds, they should be at (or at least very close to) their sampling site in the gyre tomorrow.

  5. Interesting though not unusual to see plants & animals using debris for nesting / protection (eg. artificial reefs); however, it would be nice to do some studies, including spectrography, to see what, if any “garbage” based chemicals are being picked up by these creatures. If these prey species are picking up toxins, those will be accumulated by larger animals, thus affecting other food chains (including ours). Are you going to be saving some of these animals for inland study to determine what and if they are ingesting plastic compounds, and are there any studies planned to see what the ocean floor looks like in terms of debris at this time?

    • They are collecting the large pieces of debris (and the organisms associated with them). They are being kept for identification and further study. I am not sure whether or not there are plans to do any chemical analysis of the organisms. I am not sure if there is a plan to do any studies of the deep sea floor associated with areas of high plastic abundance. We considered doing that as part of the SEAPLEX cruise, but because the sea floor is very deep in the gyre, it would have used up most of our sampling time to deploy and recover coring equipment. As a start to the question, we are examining samples from the middle of the water column (400 to 2000 meters depth). If plastic particles are found at those depths, it is more likely that plastics are making it to the sea floor.

      • Thank you for your response. This activity must be keeping you very busy and taking your time away from your studies. My sympathies.
        Questions: It is apparent many of these particles are very small as a result of breakdown (UV, collision, whatnot). Can you determine the minimum size these plastic particles are breaking down to? (eg. dust sized, or further, such as nanometer?). If so, what would the effect be on fish gills (accumulations on gill surface?) and bottom feeders (such as clams)? It seems that given the minuet size, organisms must be ingesting these particles. I realize examination of bottom feeders will be impossible at this time and current ocean depths; perhaps later land based research based upon your particulate findings may answer that question.
        Also: Any plans to examine stomach & intestinal contents of sample species to determine if there are any clumps of this material accumulating, which would lead to malnutrition symptoms through intestinal blockages or “full” stomachs? Thank you for your time, good luck, and have a fun and interesting time.

      • It does take time to answer the questions, but in the long run, I definitely think that it is worth it! Increasing interest and public literacy about science helps all scientists in the long run!

        We are looking into the small particles. Slides are being made to look at phytoplanton and microzooplankton. Those slides will also be analyzed for plastic particles. That will go down to the micrometer size range. At this point, we are not looking at anything smaller than that. There aren’t any plans to look at the impacts on fish gills or other delicate features at this point, but that is a very interesting idea. We don’t know if the plastic particles are reaching the deep sea floor, but that is something that Chelsea Rochman is very interested in and hopes to investigate in the future. There are plans to see if the zooplankton are ingesting the plastic particles, but I’m not sure how those are going to be conducted. I know that there are plans to investigate the gut contents of the fishes.


      • Thank you for your time and answers. Perhaps a spectrographic analysis of the zooplankton would reveal if they have ingested plastic compounds that are too small for microscopic detection. However, I doubt you have a spectrograph onboard! I get the feeling that the ocean floor sediment is being covered in a sludge composed of plastic particles which in turn are covered in biofilm. Would be interesting to see the effect on filter feeders. I understand such studies are impossible given the equipment you have onboard – send my sincere regrets to Chelsea; I know how frustrating that can be. I’m very curious as to just how far this plastic is “decomposing” and its effect on the ocean fauna. As small as the particles are, it seems ingestion will be certain in some species. And if you folks decide to catch some fish for dinner, an “unofficial” microscopic examination of the gill structures may prove interesting. I’m thinking you may find plastic particles in the gills (which may impact the fish’s respiration, reducing size.) Boy, do I wish I was there to do some sampling & study on this! Thanks again.

  6. Where did all this trash came from??

    -cvhs student

    • The trash came from people! Trash was dumped off of boats, washed into the ocean by rivers or through storm drains, or through any other way that trash gets anywhere. The plastic doesn’t really break down and so it stays around for a long time. Also, the physical oceanographical forces aggregate the plastic into the same general area, so there is a higher concentration in certain spots.

  7. For how long was the plastic in the sea?


    • We have probably been putting plastic into the sea since we started using plastics on a regular basis. Once the plastics get into the ocean, they don’t really break down, so they stay around pretty much forever as far as we can tell.

  8. Are fish going to have any deformations
    because of the trash???….

    • Probably not, but it is possible. In aquariums, people often use plastic as a place for fish eggs to attach. However, there are some types of plastic that are toxic.

  9. Can the fish larvae grow without being on the plastic?
    -CVHS student.

    • The eggs would need to be attached to something. A more natural attachment item would be something like seaweed or driftwood.

  10. How can the fish larvae survive on the plastic?
    -CVHS student.

    • The eggs will hatch and the fish will be carried away from the plastic.


  11. […] Previous pictures have shown fish eggs attached to pieces of plastic.  Here are some flying fish eggs that were found attached to a bird feather, a much more natural settlement site.  Photo taken by Jim Leichter. […]

  12. While out lobstering yesterday in maine I came across some strange eggs floating. I picked them up. The best way to describe them would be to imagine bubble wrap, the bigger ones with the bubbles about the size of a golfball. Inside each bubble there was what looked to me like some kind of crab, possibly hermit.
    There were problably a dozen or so bubbles each having legs like a crab in like a fetal position.The entire section was approx 18″ x6″x3″. It was very clear in color just like bubble wrap . The species in the bubbles were orange.
    I have no idea if this is a natural egg formation or if it is some sort of combo of real eggs attached to something man made. If I were to guess, I would say that it was natural. chris



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