Monday, July 6, 2009
Day 25 and 26
Now let's talk trash. The weekend was jam-packed with chasing down and wrangling debris and dissecting fish, constantly reminding us of the burden mankind has put on this vast and precious ecosystem. Here is Drew's description of the plastic debris we have been encountering:
"There was one 5 minute section where we found 4 plastic fishing floats along with numerous plastic bottles, rope and fragments. All in all today we scooped up 12 plastic floats and about 2 dozen other odd pieces of plastic debris. I can’t even begin to count how many pieces we did see but were too small for the pole nets and or too far out of reach off the boat. No matter how hard we tried, we just couldn’t pick up all the trash we see…it is impossible!
Our manta trawls today were the highest plastic concentration we have seen yet on this trip…and in my case the heaviest I have ever seen and we are still way outside of the center of the trash vortex. The pictures are from 2 ea. 2 hour trawls covering 1 meter wide by 6 miles long. The white, green, red, and light blue are plastic bits. The dark blue is jellies and the brown is assorted plankton organisms."
Captain Moore's account of the plastic debris observed:
"On Independence Day alone, we recorded 34 large objects netted, including a dozen fishing floats, a hairbrush, a Japanese survey stake (definitely not from a ship), and a PET bottle of Mitsoya Cider. That does not include the many smaller bits we scooped up and didn’t record in our “collected debris log.” I can imagine young people on voyages in the not so distant past, when the ocean was teeming with life, excitedly netting up fish and other sea creatures in abundance. I see the same excitement in my young volunteer crew shouting and netting up debris in an ocean teeming with trash. Of course, our longest handled net can only reach out about ten feet from the boat, so we see many, many more pieces floating by than we can collect. In fact, Nicole did a stopwatch survey from the starboard bow and counted 217 pieces of plastic in 20 minutes or a little more than 10 pieces per minute. We are well and truly in the Subtropical Convergence Zone, as described by the NOAA Marine Debris Program, a band several hundred kilometers in width centered around 30 degrees north latitude, and stretching from far offshore California to far offshore Japan. One of our goals is to see how levels of plastic pollution fluctuate within this area.
We have another species to add to our list of fish that have ingested plastic particles. I netted up a fishing float with a long tail of rope heavy with barnacles and a 9” Chub (nenue in Hawaiian) came up with the float. Chubs, genus Kyphosidae, have extremely long digestive tracts and “use bacterial fermentation to extract maximum nutrition from their diet of seaweed.” (Guide to Hawaiian Reef Fishes, by Hoover.) Christiana was surprised to find on dissection, pelagic crabs in the stomach. In addition, she found two small plastic fragments along with the real food.
Drew spotted the first glass fishing float of the trip and we were able to grab it for his collection. He got a similar large green glass float on the 2002 gyre voyage." (See picture to the left of Jeff with the glass float)"