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Ocean Sampling Day – Taking the Pulse of the World’s Oceans

A diver collects water samples.

Smithsonian scientist Chris Meyer is collecting water samples as part of the Pilot Ocean Sampling Day in 2013 on Moorea, French Polynesia.


Gustav Paulay

If you are a bird watcher you have probably heard of the Christmas Bird Count. The first one occurred on Christmas Day in 1900 at a variety of locations throughout North America, and it has since expanded to become the largest citizen science project in the world. Teams of volunteers go out and compile lists of all the birds spotted within a 15-mile (24 km) circle in many different places. The project has proven invaluable for keeping track of how populations of birds have changed through time.

Now comes the salt water equivalent—Ocean Sampling Day—which will take place on Saturday, June 21, to coincide with the northern hemisphere’s summer solstice. This will be the largest ocean sampling effort ever orchestrated on a single day. Over 170 sites globally will participate (see map below), ranging from Antarctica to Iceland and including the four Smithsonian field stations in Chesapeake Bay, MD; Fort Pierce, FL; Carrie Bow Key, Belize; and Bocas del Toro, Panama.

Map of sites participating in Ocean Sampling Day 2014.


Micro B3 program

What will be counted in this first-of-its-kind effort? You may be surprised that the targets are not large creatures like fish or marine mammals. Oddly enough, when trying to do something as large as taking the pulse of the entire ocean, it is easier to start with the ocean’s smallest creatures—the microbes. It turns out that microbes are a powerful way of assessing the health of the ocean because they drive many, if not most, of the processes vital to ocean and human well-being. Although we cannot see the majority of them with the naked eye, marine microbes produce over 50 percent of the oxygen that we breathe and account for more than 90 percent of the ocean’s biomass. Over 5 million microbes can be found in one teaspoon of seawater and they play important roles in the ocean where they recycle nutrients and serve as food for larger organisms. We are only just beginning to understand their diversity, distribution and function on a global scale.

These counts won’t depend on microscopes because although microscopes can be used to count microbes, they aren’t very helpful for identifying them. Fortunately, new DNA sequencing technologies allow researchers to not only determine which microbes are in the sample, but also what the microbes are doing. The process, which took three years to develop, is relatively simple: take a water sample, measure the conditions (such as temperature and salinity), screen the contents through a tiny micro-filter, and send those samples off to be analyzed.

By sampling on the same day and the same time, the project will create the first comparable global marine microbial profile—helping scientists standardize methods, create a network of coordinated partners, and create a common pool of data that can be shared among the whole scientific research community and the public.

The project is being coordinated through the European-lead Micro B3 program (Biodiversity, Bioinformatics and Biotechnology), and the Smithsonian is playing a key role, by storing duplicate samples in its brand new BioRepository. Given that new technologies are developing rapidly, having those samples in the deep freeze will allow future researchers to go back in time to sample past ocean conditions in ways we can only imagine today.

Editor's note: You can join in and help with sampling! The teams of scientists are looking for your help if you live near a body of water and can take some simple measurements. Find out how to join in on the fun.