One man’s trash is an ocean fly’s treasure

Hey there, time traveller!
This article was published 11/05/2012 (4906 days ago), so information in it may no longer be current.

And now, a message from the land of I-told-you-so science. The I-told-you-so? That we may eventually poison ourselves out of a home on Earth, but other species may adapt just fine to what we leave behind.

For years, ocean scientists talked about anecdotal studies that found wood pulp in major water sampling projects in the open ocean. The culprit? Millions upon millions of flushed sheets of toilet paper.

The ubiquitous fibres were perfect for making their way around the globe: There was plenty of supply, and toilet paper is designed to break down quickly into small fragments. The little sailors were then free to drift their way around the world’s oceans.

Now, the Scripps Institute of Oceanography at the University of California (San Diego) is mapping a new series of sailors: fingernail-sized scraps of plastic garbage that are spinning in the North Pacific gyre, a gently turning coil of currents in the Pacific Ocean. Known as “the Great Pacific Garbage Patch,” the gyre has increased 100-fold over the last 40 years.

There’s enough plastic there that a Scripps study found last year that nine per cent of ocean fish have plastic in their stomachs at any given time. The study estimated that fish are eating 12,000 to 24,000 tonnes of shredded plastic a year.

That might make a great weight-loss aid for fish if they needed such a thing — the plastic fills them up but is virtually indigestible.

But the new study says there are those who are benefiting from having massive drifts of plastic across the ocean’s surface.

Tiny flies called sea skaters (like water-striders — but ocean-dwellers instead of pond creatures) are laying scores of eggs on the plastic floating in the gyre.

Normally, the flies are limited by the amount of floating debris they can find to carry their eggs until hatching. Now they are no longer limited to feathers, pumice and seashells, the flies are undergoing an unprecedented population boom.

The huge increase in flies may have a benefit for their traditional predators, but the research points out a sudden increase in a particular species may have unexpected results for other creatures in a fully integrated food web. In part, it appears crab will do better, and other fish perhaps not as well.

What does that mean?

Well, to be flip, one man’s trash is another fly’s treasure — but what’s good for the fly is not necessarily good for the ocean.

Microbes, sea skaters and cockroaches may do just fine.

And the rest of us? Well, we haven’t proven to be particularly adept at keeping much of anything out of the ocean, nor have we generally minded what we do with the environment in any cohesive way.

And what was that other saying? As ye sow, so shall ye reap.