If you open up a magazine about marine technology, you will
most likely be inundated with advertisements and articles for equipment that can
resist corrosion, extreme pressures, and “biofouling”. These are all major
threats to the successful deployment of equipment, particularly if it is
intended for long-term use. This applies to oceanographic equipment as well: any
metal pieces on our equipment must be corrosion resistant, and the sensors will
universally work better if organisms don’t take up residence on or near them.
A couple days ago we recovered a length of rope floating in
the ocean that we had passed several times while doing a circuit around a
region. While rope may seem innocuous, if a ship drives over one and it becomes
tangled in the propeller, it can go from a piece of trash to a huge issue, so
it made sense to pick it up. When we get it on deck, we discovered that it was covered in gooseneck
barnacles. Unfortunately for the barnacles, taking the rope out of the ocean
means they won’t be able to survive, but the threat to navigation in this case
seemed important.
Close up view of the top of a float. Notice the tiny grain-like creatures clustered around the bottom of the ports. (Photo credit: Rosalind Echols) |
When we picked up our floats a few days later, we noticed that
there were tiny organisms growing on them, mostly clustered where there are
sharp right angles that create some sort of crevice. Upon further inspection at
50x magnification (using a microscope that looks like its heyday was in the
1950s), we pursued some amateur biological classification and decided that they
were probably barnacle larvae. In the larval stage, like many other marine
organisms (including benthic ones, or those that ultimately live on the bottom
of the ocean as adults), they drift freely in the ocean until something comes
along that they can attach to. The odds of them finding one of the floats,
given the immensity of the ocean, seems staggeringly small, and yet in only 5
days there were hundreds clinging on.
The tiny critter (barnacle larva?) at 50x magnification. Picture taken with a phone through the microscope lens, so please excuse the quality. (Photo credit: Rosalind Echols) |
This is just one example of the phenomenon of biofouling,
which could also be described in a more positive light as the impressive
determination of marine organisms to survive. Any instrument that is going to
be in the ocean for a long period of time will likely have to contend with this
at some point.
So interesting! Great post!
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