Cyborg Mussels Could Serve as Environmental Warning Systems

We know that researchers can use mussel shells to measure historical levels of fracking pollution, and they’ve also been known to test positive for opioids. Now a team out of North Carolina State University is working on a different idea: Hacking mussels with sensors so that they can function as a real-time warning system for pollution in the water.

At its simplest, the idea is based on how mussels eat. Mussels are filter feeders, and they feed asynchronously – meaning there’s no apparent coordination between mussels to either eat, or not eat, at exactly the same time. All that changes, however, when there’s something noxious in the water. The mussels will clam up, so to speak, all at once in order to protect themselves from potential contamination.

By attaching inertial measurement units (IMUs) to each half of a mussel’s shell, the sensors are able to detect if a mussel is open or closed, and how widely open it is. In order to keep costs down and ensure scalability, the researchers are using commercially available IMUs – similar to those found in cell phones – but just applying them in new ways.

Once the sensor has the information, it then sends it back to a centralized data acquisition system that’s mounted to a stake nearby and powered by solar panels.

Alper Bozkurt, co-author and professor of electrical and computer engineering, describes the concept as being not unlike a Fitbit for bivalves:

“Our aim is to establish an ‘internet-of-mussels’ and monitor their individual and collective behavior. This will ultimately enable us to use them as environmental sensors or sentinels.”

Jay Levine, a co-author of the research and professor of epidemiology at NC State, likens the concept to the now-infamous use of canaries as an early warning system:

“Think of it as a canary in the coal mine, except we can detect the presence of toxins without having to wait for the mussels to die.”

Lest anyone has ethical concerns about the exploitation of mussels, the goal is not simply to hack these creatures for the good of humanity, however. The researchers also hope to learn more about the health and wellbeing of mussels themselves – as Levine explained in a press release announcing the research:

“…it will help us understand the behavior and monitor the health of the mussels themselves, which could give us insights into how various environmental factors affect their health. Which is important, given that many freshwater mussel species are threatened or endangered.”

Specifically, Levine pointed to the ability to monitor behavior in real-time as a powerful tool in understanding how environmental changes affect mussel populations.

“What prompts them to filter and feed? Does their behavior change in response to changes in temperature? While we know a lot about these animals, there is also a lot we don’t know. The sensors provide us with the opportunity to develop baseline values for individual animals, and to monitor their shell movement in response to environmental changes.”

It certainly would be nice to know there is a threat before mussels end up cooking on a hot beach.

The paper, “An Accelerometer-Based Sensing System to Study the Valve-Gaping Behavior of Bivalves,” is published in the journal IEEE Sensors Letters. Ph.D. students Parvez Ahmmed and James Reynolds were co-lead authors on the paper.