Small World

Picking forams on a rolling ship
One of the most delicate parts of our job at sea happens at the microscope—something that sounds routine, until the ocean decides otherwise. Out here, we’ve been collecting tiny marine organisms called foraminifera—single-celled protists that build shells (called tests)—from the surface of seafloor sediments. While microscopic, these organisms are incredibly important in paleoceanographic research, as their shells preserve information about past ocean conditions.
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In the upper layers of the cores we recover, foraminifera are not just buried in the mud, they also often cluster on hard materials like rocks, sponges, bryozoans, and other seafloor debris. These tiny specialists seem to prefer something solid to latch onto—living right at the sediment–water interface, where the bottom of the ocean meets the overlying water column.

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Seasick scopes and foggy views
After retrieving these hard substrates from the top few centimeters of each core, we bring them to the microscope for picking. But picking forams at sea presents challenges you might not expect. Even when the waves aren’t dramatic, the motion of the ship is amplified in the microscope, causing the image to sway and bounce. Looking into the scope under these conditions can quickly bring on seasickness—especially when the ship is pitching enough to send all the swivel chairs rotating around the lab.

We learned early on that picking sessions have to be timed carefully. If the ocean is too rough or a storm system is passing through, it’s better to wait. We’ve even had to tie down the microscope with line and metal braces to keep it steady on the table. Everything in the lab has to be secured, including our trays, vials, and tools—one rogue wave and you risk losing hours of work.

We originally struggled with an awkward scope setup that we endured for hours each day, but after so long at sea some rearranging was required and we now have a much more ergonomic space. We also use special picking trays with narrow grooves, which help stabilize the sample as we carefully tease apart the materials and extract the tiny foraminifera.
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And while most days a thick fog blankets the view outside, the microscope reveals a whole hidden landscape of life clinging to fragments of the seafloor.

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Tiny victories
Despite the motion, the fog, and the challenge of working at sea, we’ve had great success. So far, we’ve filled nearly 100 cryovials with foraminifera and have several more stations to go! These samples will allow us to explore foraminiferal communities at the sediment surface, complementing the geochemical and micropaleontological studies focused on the deeper parts of the cores.

Pairing foraminiferal ecology with geochemical profiles collected by collaborating teams on this expedition will help build a more detailed and dynamic picture of ocean change—linking what lives on the seafloor today to past environmental conditions.
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We may not see much of Greenland’s dramatic coastline past the fog, but each core we recover brings the seafloor right to our fingertips. There’s something exhilarating about that first look—even after 40 multicore recoveries, it never gets old. And when that material goes under the microscope, that sense of wonder only grows. For me, it’s a chance to see an entire hidden world, magnified.

Author

Ashley Burkett