Day 6- First manta trawl!

Noon position: 24°52'40.80"N 128° 9'57.60"W

It’s Day six and we are officially 2/5 of the way to Hawai’i. Day six has been a day of firsts-- the first plastic trawl of the trip, and our first fish catch (a Mahi Mahi!).

Let’s start with the trawls. While the winds have been against us in terms of maintaining our original course, they have put us in an area of the Pacific which had never been sampled……until today! See the map below or Click here, to view more maps of our previous sampling areas. We deployed the first Manta trawl, a device that captures surface debris in a fine mesh net, at 9am. This process was akin to riding a bike for the Captain and veteran crew Drew, Joel and Jeff, and a learning experience for the newbies (Christiana and myself).

After an hour of towing the trawl we pulled it in to find a strikingly low amount of plastic. Among the plastic identified was some line, a few hard plastic fragments, and a piece of a clear plastic label on which we could decipher the letter “d”. Among the life identified in the sample was a button valella, some copepods, a juvenile Pacific saury, and tiny gastropods with gorgeous purple shells. (See image of sample at the top of this message.)

The evening brought on trawl number two. This trawl gave us the opportunity to experiment with a tethered underwater camera, which Joel was able to rig to record the underwater flow into the Manta trawl. This was a significant in that it confirmed the integrity of our surface sampling methods. We ran the evening trawl for an hour as well, finding results similar to the morning trawl--very little plastic.

Obviously the low quantity of plastic present in samples is good news, but it does highlight a key point. Throughout fifteen years of sampling, we have yet to bring in a trawl completely void of plastic. While standing on the foredeck today, the Captain was able to identify plastic fragments flowing past the vessel. We also spotted some larger debris, a 5 gallon bucket which managed to evade our collection efforts. The point is, even in this new sample area in which our trawls our producing comparatively low amounts of plastic-there is still enough debris present for us to visually register and in our trawls. The relatively low amount of plastic also points to the possible delineation of the boundaries of an accumulation zone, although it is far too early in the data collection process to make any definitive conclusions. Joel noted that during the JUNKraft expedition last summer he and Marcus Eriksen noted a similar trend in abrupt transitions in plastic accumulation as they skirted the south edge of the accumulation area.

And finally, after five days of rigging fishing poles and hand lines, we had our first catch. Christiana kept the liver and other organs and tissue for future analysis.

Best wishes from the Capt. and Crew

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