Plankton Every Day is a blog by Kate Zidar about citizen science and untethered living. These are my micro and macro observations about the daily practice of staying afloat!
Here at Plankton Every Day, we are big fans of citizen science. “Go do some science!”, I like to say. There is a new, fantastic smartphone app called Secchi App that crowdsources phytoplankton measurements from all stripes of seafarers around the world. It was created at Plymouth University in the UK, and the app is free. To participate, you need a smartphone and a Secchi disc.
What is a secchi disc, you ask? It is a simple device that was invented in 1865 by Angelo Secchi, a Jesuit scientist and leader in astronomy, oceanography, meteorology and physics. It is still a standard tool in use today for determining the turbidity, or clarity, of any waterbody. Measuring turbidity is essentially a proxy for measuring plankton, silt or other suspended solids in water. Clear water = low turbidity, and cloudy water = high turbidity.
According to Richard Kirby, a Marine Institute Research Fellow at Plymouth University, a Secchi disk is “arguably one of the simplest marine sampling devices ever created.”
Here is Richard:
I will attest to the simplicity of this device. Similar to my very favorite scientific instrument, the Bucket on a Rope, a Secchi disc is simply a disc on a rope. It is weighted so that the disc can be dipped straight down in the water column, and the rope is marked for distance (or the rope itself is a measuring tape), so that you can measure “wet rope” aka “depth”.
You send the disc down until you can no longer see it. You bring it up until you can just barely see it again. Then you carefully lower it until it is just disappeared. Measure wet rope, log depth measurement into the app, and ping for GPS location.
I love this marriage of old analog tools and modern gadgets. Go do some science!
The transformation of the global waste stream into mostly stuff made of single-life plastic was presaged in the 1930s with the invention of polyethylene (your plastic bottle), and then kicked into overdrive in the 1960 when the stuff became cheap to make. Since then, human impacts have ushered in an new ecological niche called the plastisphere.
This is a more descriptive name IMHO than the garbage patch, trash vortex, etc., which effectively conjure images of great rafts of chunky landfill debris. Surely, big plastic is a devastating issue for marine ecosystems, evoking heartwrenching images of “ghost nets” that break free from commercial fisheries, plastic trash on the outskirst of the deep sea floor, and the ubiquitous bird belly full of plastic caps. Consider this the “charismatic macrofauna” of the plastisphere.
But wait, there’s more.
Most ocean plastic is small, like plankton. It is there in large amounts mixed in with the foundational slurry of the food web. And now researchers are following natural selection as it plays out in this tiny-yet-vast realm of the plastisphere.
As it turns out, while plastic “eats” our oceans, something eats the plastic.
For about four decades, it’s been known that plastic is collecting in the open ocean. Now, scientists have found this debris harbors unique communities of microbes, and the tiny residents of this so-called plastisphere may help break down the marine garbage.
Inhabitants of the plastisphere include members of a group of bacteria, the vibrios, known to cause disease, and microbes known to break down the hydrocarbon bonds within plastics, genetic analysis revealed. But most important, the communities of microbes on the plastic pieces were quite different from those found in samples of surrounding seawater.
“It’s not a piece of fly paper out there with things just sticking to it randomly,” said study researcher Tracy Mincer, an associate scientist at the Woods Hole Oceanographic Institution, referring to the plastic. “There are specific groups of microbes that are attracted to that environment and are adhering to it and living on it.” -Wynne Parry
Last week I took a field trip to the Dutch Kills tributary of Newtown Creek with Drs. Michael Levandowsky and Sarah Durand to sample plankton. Sarah is a fixture on Dutch Kills, and is currently enjoying her sabbatical from LaGuardia Community College (although sabbaticals do tend to become as full of responsibility as ever, I am learning), located steps from the infamous Superfund site. She and her colleague Dr. Holly Porter-Morgan, the director of the environmental science program at LaGuardia, have regularly brought their classes out to sample water and benthos on the creek, and are the resident scientists of Newtown Creek. Michael I have introduced already.
Finding a time for all three of us to get together on my favorite underdog waterbody was something I had been looking forward to for awhile.
Michael on plankton and Sarah on dissolved oxygen.
Despite popular opinion, Newtown Creek is alive. I would never use adjectives such as “clean”, “pathogen-free” or “high-functioning”, but I can state with some authority that Newtown Creek is surprizingly alive. The ecosystem that exists today in the backyard of the Industrial Revolution is what one might call “impaired”, hamstrung by historic contamination and persistent sewer overflows, but it limps along (and occasionally leaps!) nonetheless.
Dutch Kills has always been fascinating to me, as it lies on a transitional borderline between the relatively good water quality at the mouth of Newtown Creek, and the “heart of darkness” further up. There is a large CSO that functions as the headwaters, and the entire tributary might suddenly turn a milky mint green, precipitate gloopy green algae blobs, and then turn a tea-like red the next day. She moves in mysterious ways.
Sarah hosted our dip, and allowed us to take a preliminary look at our findings back at the lab. We used two different tows, one of coarser and one of finer mesh. This is what we saw in the coarser mesh:
Clockwise from top left: Possibly a freshwater alga, a barnacle larva, something of botanical origin that stumped us, and a skeletonema.
Michael made off with an aliquot of the fine mesh sample and reported… “I looked at the sample from the 10 um tow and it’s rich in phytoplankton. Skeletonema dominates, but there are also dinoflagellates, and much else.”
