Thursday, June 18, 2009

Answers to Student Questions

A few days ago we received a great question from an East Hills 4-H student from San Leandro California USA- here is the question;

"I found a web sight that does not make high remarks about you. including the amount of plastic that you have collected while trolling. they say in 24 hours of non stop trolling you found a minuscule amount of plastic. i would like to know some actual facts."

And here is our answer;

Your investigative instincts are great! When you are looking at data, it is always important to check your facts. Part of the scientific process is putting your data out in the open for others to evaluate and criticize. One of the most important aspects of checking facts is understanding the source of the information to determine if there might be reason for bias in the information presented.

The website you are referring to, called "Save the plastic bag", was created with a very clear intention-to keep plastic bags around by pushing people to believe that plastic bags are not an issue in the marine environment. But our research has shown this is not the case. In fact, just two days ago, while swimming around the boat, Captain Moore netted a piece of a plastic bag (See the picture above). We were nearly 1000miles offshore at that point. There is a problem with one time use plastic bags if they are finding their way into the middle of the ocean.

The trawl the website referred to was part of an awareness campaign called "Message in a Bottle". It was not intended for research purposes and the net used was much smaller than the standard Manta trawl that we are using. Furthermore the crew of the plastic bottle raft "JUNK"passed on the outskirts of the accumulation zone. So it is especially significant that plastic was found in this trawl, it shows how widespread the problem really is. Aboard ORV Alguita we have never conducted a trawl that did not contain at least some plastic. In 1999 we found that there was an average of 334,271 pieces of plastic/km2 and roughly 5,114 g/km2 of plastic in our study area, a part of the North Pacific Subtropical Gyre now known as the Eastern Garbage Patch.

Regarding the statement that the crew “[caught] only one fish with plastic fragments in its stomach”, it must be noted that the goal of the "Message in a Bottle" project was to raise awareness about plastic pollution; their primary goal was not dissecting fish to look for plastic in their gut. However, we have dissected fish from ORV Alguita's 2008 voyage and found that 35% contained plastic in their stomachs.

Before writing off plastic in the water as a non-issue, there are a couple things to remember. 1) It is illegal. According to MARPOL Annex V (an international agreement regarding marine debris) it is illegal for any plastic to be released into the water. Along the coast of California there is a regulation set for large debris (such as plastic) which states that there can be 0 discharge of debris into the oceans. 2) Plastic is harmful to marine life, even in small amounts. Any amount of plastic in the ocean is unacceptable because it breaks down into bite size pieces which are consumed by the animals (including both fish and birds). This can block the digestive system of the animal or take up space making it difficult for the animal to feed. In addition, plastics are known to contain chemicals that can be toxic to humans and animals. Plastics also adsorb harmful substances onto their surface, up to 1million times more than in ambient seawater (we will discuss this research in more detail soon!).

Keep up the critical eye, you are on your way to becoming a great scientists!
-Captain and Crew of ORV Alguita-


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