Microbes are core components of the ecology and functioning of all ecosystems, including plants, animals and engineered systems. While there is a burgeoning understanding of the abundance and diversity of microbial communities, comparatively little work has focused on the impact of “grazers” (small plankton that eat microbes) on their mortality.

The importance of grazers is broadly recognized, but there remain significant technological challenges to characterizing and quantifying these organisms. This project team created and tested a beta version of a “planktoscope” that has the ability to automatically take pictures of and identify larger plankton (including zooplankton/predators) from marine samples. 

Team members worked in the Co-Lab on campus in Durham to build the device using open source instructions. This initial part of the project included assessing current hardware and software design suggestions in the context of goals and hardware availability, making recommendations for initial modifications and building the first version of the planktoscope. 

In the second phase of the project, the beta design was evaluated at the Duke Marine Lab in Beaufort for two applications relevant to energy and environment: a coastal marine time series with weekly microbiome sampling; and marine microalgae ponds for sustainable production of food, feed and fuel. 

For the first system, sampling occured as part of the Pivers Island Coastal Observatory and leveraged ongoing weekly time-series monitoring of coastal waters. The second sampling occured as part of the Marine Algae Industrialization Consortium, where marine microalgae are being grown at commercially relevant scales. Broad testing was used to determine the effectiveness of identifying and quantifying diverse types of plankton, and to determine the robustness of the instrument. 

After initial testing, the team brainstormed and suggested design changes, conducted a final evaluation and wrote a future design recommendation report.

Timing

Fall 2022 – Spring 2023

Team Outputs

Planktoscope prototype 

Data from prototype testing in a natural marine ecosystem and an engineered system

Report

Image: Zooplankton Sampling, by NOAA Great Lakes Environmental Research Laboratory, licensed under CC BY-SA 2.0