Another Algae Bloom … Now In Fresh Water

There’s more than one algae bloom revealing itself in the Severn River watershed — in the middle of winter 2020.

Our intrepid Field Investigator, Izzie Ketcham, has discovered a green tide in a non-tidal freshwater pond that feeds into the Severn River via Chase Creek.

This is the green color in the picture at right in Timberneck Pond inside the Pines On The Severn Community.

Izzie discovered the algae bloom as part of her work with SRA to prepare a study protocol for SRA’s new GEMS Expedition.

This citizen-science based program will update the GEMS On The Severn report produced by Colby Rucker for the Severn River Commission in 1988.

After noticing the odd green color on the pond, Izzie had her assistant take samples (see pic at right), which were sent to Maryland Department of Environment (MDE) for identificationField Samplingion.

MDE’s Nick Kaltenbach identified the cause of the green hue as a green algae, Chlamydomonas, with a sample count of 6302 cells/ml.

Nick explains that “while there were other constituents in the sample (unpigmented flagellates and protozoans), the color was due to the Chlamydomonas.”

He also pointed out that, “this genus has hundreds of species and is cosmopolitan.  Many are common in enriched ponds, but some are found in snowfields, soil, bromeliads, just about anywhere there is water.”

Late last year, another algae bloom, a red tide, spread throughout the Severn River, lasting from Dec. 23 and through, at least, the first week in February, 2020.

Click here to read about this red tide event in the river.