Seeking sailors to help measure phytoplankton populations.

Richard Kirby, a plankton biologist at Plymouth University’s Marine Institute, United Kingdom, has observed that phytoplankton—microscopic organisms dependent on photosynthesis—are being affected by rising sea temperatures. Responding to research indicating a dramatic decline in phytoplankton populations, Kirby says, “Phytoplankton underpin the marine food chain; without them the seas would be a barren wilderness. Like all marine creatures, phytoplankton have a preferred optimum sea temperature no matter where they are in the world, and therefore they will either move to different areas or decrease in number if the sea temperature changes.” Kirby’s citizen science app to monitor phytoplankton worldwide was launched on February 21, 2013 and is now available to sailors, fishermen, and recreational boaters alike. Sam Lavender, whose company is maintaining the Secchi Disk database, says, “We hope that all seafarers, whether a sailor or angler, will enjoy taking part and will see how easily they can help create a truly unique and important scientific database for future research.” To use the free app, participants must make their own Secchi disk—a simple white disk attached to a measuring tape—lower it into the ocean (away from estuaries or other sediment-rich areas), record the depth at which it disappears, and enter the information into the app. Because the organisms exist only in the sunlit sea surface, the shorter the Secchi depth (the distance where the disk can no longer be seen), the more phytoplankton are present. The researchers have created online presentations that show the process in more detail. They say that the interactive dataset will eventually be linked with data from satellites monitoring the oceans to create a resource for scientists and the public. Scientists fear that the population of phytoplankton is in decline due to rising sea temperatures. Image courtesy of Richard Kirby, Plymouth University, Plymouth, United Kingdom.