Wednesday, February 6, 2008

Calm after the synthetic storm

Our noon position: Longitude 34 28.561 N, Longitude: 158 53.309 W

After yesterday’s flurry of activity, today was considerably calmer….dead calm in fact. We raised our Spinnaker for the first time at daybreak, to maximize our wind power. We have many miles to go yet, and need to travel as much as possible by wind. Crew had a chance to return the boat to “ship shape”, snag an Albacore, and collect our daily sample, the same collection we’ve come to expect of plastic particles and tiny pelagic creatures.

Now to respond to a few of yesterday’s comments:

Paul S. asked, “Do you mean to say you trawl an area approximately 3 feet wide, 6 miles long, and come up with only 1/3 of an ounce of plastic?” We all chatted a bit about this during dinner – and may comment further in the coming weeks. For now, here’s a response from Marcus:

“10 grams per 6 nautical mile trawl is a subjective estimate based on years trawling in and out of the North Pacific Gyre, near and far from shore. This is a rough estimate that might not seem like much, but you’ve got to consider the size of our playing field. Our trawl is three feet wide. A six nautical mile trawl covers a little less than two football fields. We’re studying an area between latitudes 20 and 40, and longitudes 130 and 170, which is approximately 2.5 million square nautical miles, representing only a quarter of the North Pacific. Still, that covers almost 3 billion football fields (2,929,900,000). SO, if we’re averaging 10 grams for every two football fields of area, then in ¼ of the Pacific we think there could be 14 ½ MILLION metric tons of plastic marine debris. “

And Tim Harvey had a question about FAD’s providing habitat for pelagic creatures. First, how great to hear from the famous Vancouver to Vancouver traveler- this is a guy who traveled the world for 2 years by foot, sail, and bike, to raise awareness about climate change! Others have asked this question before, a logical one, so I’ll direct you back to an earlier answer from Captain Moore. Here’s an excerpt of his earlier answer:

“So what's wrong with the "propagation of fauna" on our trash in the ocean? Aren't we just providing places for things to live? There are at least two problems with this. One is that plastic trash travels slowly on ocean currents, which allows the organisms attached to adjust to changes in climate and water temperature. They may end up colonizing areas where they were never known before and out compete local species. This leads to a loss in what is called "biodiversity." The second problem we have been discussing onboard Alguita is….”

Full answer available here:

To illustrate this concept, here’s a few photos from yesterday’s debris removal, an ingeniously camouflage pelagic crab on a laundry basket (below), a group of anemones (Epiactic Prolifera) rooted on a plastic fragment (left), and Marcus holding up detergent bottle covered in growth(at the top of the page.) These are all excellent examples of plastic detritus providing habitat, as well as marine “taxis”, allowing species to hitch rides to oceanic regions in which they don’t necessarily belong.

More to come manana about sailing, ghost nets, and a special recipe for those concerned about safe fish intake.

Aloha and gracias from the Captain and crew of the ORV Alguita!


Thump Thump Eyes said...

Good luck on your voyage, you're doing the human race a big favour by investigating this rubbish dump. I hope you get a huge swell of support from around the world, because this problem belongs to all of us!!

There was a story about your voyage in the Australian news the other day, here is the link if you havent already seen it...and I've blogged about it as well to spread the word about your journey.,23599,23156399-2,00.html

Once again, good luck and may the weather be kind to you:-D

Knucklehead said...

I forgot to ask you .. Is it Ok to add your blog on my list of usual suspects in my blog.

Paul S. said...

Thanks for the response. I wasn't sure I understood the numbers correctly -- apparently I did. What we therefor appear to have is a very weak dilution of plastic particles over a very large area. From that you can calculate (as you have done) a very large estimate of the total amount of plastic in the North Pacific, and that has some impact, in that people are surprised that our detritus is so pervasive that it extends to what we laymen previously thought of as the pristine and remote parts of the ocean. Put to get people to make the kinds of changes necessary to fix this problem there will have to strong evidence that this plastic is not only there, but that it is causing harm. Has there been research, or are you planning research, that will make the case that fauna or humans are being harmed and that will attach dimensions to that harm? Put another way, do we have an answer to the question, "Yeah it's gross, but why should I put it high on my list of world problems that need our immediate attention?" The best answer I've seen to that so far is the photo of the albatross with a gut filled with plastic bits. Is there a way beyond the anecdotal to establish widespread harm to marine wildlife? Or some other harm? Weak dilutions can cause real harm and spur remedial action -- witness the response in recent decades to toxics in the parts per million in freshwater -- but there has to be a widespread understanding of the harm before action will be taken.

Steve P. said...

"Still, that covers almost 3 billion football fields (2,929,900,000). SO, if we’re averaging 10 grams for every two football fields of area, then in ¼ of the Pacific we think there could be 14 ½ MILLION metric tons of plastic marine debris."

Is my math off? I'm getting 14.5 million kilograms - 14,500 metric tons.