In for the Long Haul

NOAA Scientists Conduct World’s Longest Plankton Tow, Surveying Pacific ‘Garbage Patch’ Along the Way


Dr. Lora Clarke.

Record-setting Plankton Sampling: NOAA’s Dr. Lora Clarke works with a continuous plankton recorder (CPR), a device towed by the NOAA Ship Okeanos Explorer that captures samples of plankton on silkscreens. NOAA scientists aboard the Okeanos are conducting what’s believed to be the longest plankton sampling on record, covering more than 5,100 miles of the Pacific Ocean.

High resolution (Credit: NOAA)

Scientists onboard the NOAA Ship Okeanos Explorer are conducting what they believe to be the longest plankton sampling on record. 

By the time the two-part project is complete, the ship will have covered a total of more than 5,100 miles in a portion of the Pacific where little is known about the diversity of these microscopic organisms that form the base of the marine food web.

The Many Forms of Plankton

Plankton consists of drifting microscopic plants (phytoplankton), animals (zooplankton), bacteria (bacterioplankton) and viruses (virioplankton) that inhabit oceans, seas and bodies of fresh water. They are the most abundant form of life in the ocean. In fact, all other marine life is dependent upon plankton for food.

Phytoplankton are the world’s No. 1 source of oxygen and are responsible for 90 percent of all the photosynthesis — the conversion of energy from sunlight into organic compounds — that takes place on Earth.


Specks of plankton cling to the CPR’s silkscreen.

High resolution (Credit: NOAA)

“This project will provide valuable information on plankton for an area of the world that has been largely unsampled,” said Dr. Lora Clarke, a NOAA Fisheries Service scientist onboard the Okeanos Explorer who oversaw the first leg of the plankton tow. “We will obtain the necessary baseline data to allow an examination of the relative richness and variety of plankton and how this might influence fish, turtle and mammal species. Understanding patterns of plankton biodiversity will help scientists to understand factors
influencing global productivity.”

Miles to Go — and Tow

Sailing from Guam en route to Hawaii in late August, the Okeanos Explorer team conducted the first leg of the plankton sampling, or “transect,” by towing behind the ship a continuous plankton recorder (CPR) outfitted by the NOAA Fisheries Service Narragansett Laboratory. This device filters plankton from the water onto rolling silk screens that can later be analyzed in the lab.

NOAA’s Dr. Stephanie Oakes

NOAA’s Dr. Stephanie Oakes prepares the CPR for another deployment.

High resolution (Credit: NOAA)

The ship towed the CPR for 14 days more than 3,100 miles to collect data on the species composition of phytoplankton and zooplankton. After a layover in Hawaii, the ship departed
Oct. 19 for San Francisco with NOAA’s Dr. Stephanie Oakes leading the next phase of the sampling mission.

Plankton or Plastic? In This Study, Both

For the second leg of the sampling mission, NOAA researchers have also teamed up with the Scripps Institution of Oceanography at UC San Diego to study plastic marine debris as they cross the so-called Great Pacific Garbage Patch, a large area in the North Pacific Ocean known for accumulations of plastic marine debris

Deploy the CPR.

Kelson Baird helps deploy the CPR off the stern of the NOAA Ship Okeanos Explorer.

High resolution (Credit: NOAA)

The ship will cross the breadth of the area and take one of the first measurements of its width by carefully analyzing plastic particles caught in both the CPR and in a surface plankton net (“manta net”).

Scientists at NOAA Fisheries Northwest Fisheries Science Center in Seattle will be testing the plastic particles for surface contaminants in an attempt to expand our understanding of the multiple impacts the debris can have on marine ecosystems. 

Plastic debris has many observable effects on marine life. Thousands of marine animals die each year from interactions with plastic litter, including plastic fishing line and gear. What is less known is how plastics affect the smallest organisms on which other marine life feed.

“The information on the biodiversity of plankton across the Pacific will be exciting to see,” said NOAA’s Michael Ford, who is leading the project. “The size spectrum of plastic particles and the size of the Garbage Patch is just as exciting. By putting the two data series together, we can begin to make connections between plankton and plastic and possibly determine how much of an impact the plastic debris is having on this part of the marine food chain — it’s an incredible opportunity.”

Marine debris.

What the Tide Brought In: Plastic trash is among the marine debris that washed up on this Hawaii beach.

High resolution (Credit: State of Hawaii)

To follow the Okeanos Explorer on its record-setting mission, visit the Ocean Exploration website

Posted Oct. 27, 2010 NOAA logo.







Plankton and bits of plastic.

Tiny plankton and bits of plastic commingle in this water sample taken in the vicinity of the so-called “Great Pacific Garbage Patch,” a large area in the North Pacific Ocean known for accumulations of plastic marine debris.

High resolution (Credit: NOAA)