How much life passes through a single one-foot by one-foot spot in the San Francisco Bay every day? Photographer David Liittschwager set out to answer that question over the course of 14 days this past spring. From a sailboat anchored in the shadow of the Golden Gate Bridge, he and an assistant used a 12-inch diameter plankton net to collect the microscopic plants and animals that were carried by the bay’s currents through a metal square-foot cube submerged in the upper water column.
What they found astounded them. In a single sample that consisted of the plants and animals collected in the plankton net over a two-minute troll at two knots they found an estimated 550,000 individual organisms. They calculated this number after counting the organisms in a smaller subsample of just ten drops of water. They found everything from juvenile jellyfish, crabs and shrimp to small crustaceans called copepods, and diatoms, which are algae encased in silica—tiny plants that live in glass houses.
Cataloguing every individual organism in the entire cube would have been impossible, but they estimated that up to 2.6 billion creatures would pass through the cube in a 24-hour period.
Read the rest of this story from Megan Molteni at Oakland North.