How Oyster Farming Helped me Prepare for the Pandemic

As an oyster farmer, I learned to deal with pandemics on a regular basis. COVID-19 was simply the first time I had to deal with one on land. Lessons learned on the water helped me prepare for today.

In 2011, when I had been an oyster farmer less than a year, a majority of the oysters in the Damariscotta River were reported decimated by MSX, an oyster disease that – while benign to people – kills oysters in the cruelest of ways to farmers, just as they hit market size. After all that work.

The same questions emerged as with COVID-19. How was MSX passing from one oyster to another? Was it through the water? Was there a catalyst? Was there a way of stopping its spread to other areas like my own?

MSX was ultimately contained thanks to the now-familiar tools of isolation and testing implemented by the Department of Marine Resources (DMR)– think the CDC for marine life. They banned the transfer of oysters from the Damariscotta river to any other Maine watershed. They also conducted testing along the coast in order to trace any possible emergence of MSX elsewhere.

In a pandemic, it is hard to know how to act. But being conservative never hurts. As the MSX pandemic was raging in the Damariscotta River, I was dealing with a different outbreak. A first-year farmer, I had outsourced the delicate, early-stage farming of small seed to seasoned farmers up the coast. When it was time to collect my oysters, the surrogate farm was reporting problems with polydora websteri, otherwise known as “mud worms,” a tiny parasite that boroughs in oyster shells, creating mud-filled “stripes” on the inside of an oyster’s shell. Excessive “stripes” result in unsellable oysters. Polydora are ubiquitous but generally don’t create problems in cooler waters like Maine’s. But the climate is changing.

Without the seed, my farm was kaput. But I didn’t want to transfer a problem to my site either, so I had samples lab tested. A scientist popped open the tiny shells and peered at them under a microscope. He found no trace of polydora. I was cleared for take-off.

A year later, out of the blue, I got an angry call from my wholesaler. My oysters were infested with gaping mud worm blisters. They were unsellable.

Thankfully the infestation was largely contained to one part of the farm. But how did they get there? Was this a new infestation caused locally or did we miss something in the lab? Just like with community spread, it was hard to pinpoint the origin of something that is everywhere. But had I acted more conservatively and not moved the seed, I could have at least known that my own actions were not to blame.

Timing has a big impact on outcomes in pandemics. It’s better to get COVID-19 now than it was in March. In the week following my knowledge of the outbreak, I called every research institute I could to seek advice. The answer was always the same: isolate, isolate, isolate. That could mitigate spread, but not help the infected.

One call finally generated a different answer: A young woman at the University of Maine had just written a senior thesis on treating polydora. A possible cure! At that point I would have tried Hydroxychloroquine! We tested this young scientist’s technique on a small scale with near perfect results.

Then we scaled up. We removed hundreds of oyster bags off the farm, emptied them into large bins filled with fresh water, soaked the oysters, and then refrigerated them. It was a herculean effort but in less than a week we had killed the polydura and returned the clean oysters to the farm.

We got lucky. But sometimes you have no choice but to wait out a pandemic. Our changing climate favors increased propagation of harmful algal blooms. In the early summer of 2019, a cloud of red tide spread South towards my estuary. Red tide does not kill oysters, but it can cause paralytic poisoning in people who eat them, so harvest becomes prohibited.

What followed was an aggressive testing regimen and a whole lot of patience. We shuttled oysters up to the DMR on a weekly basis and waited for two consecutive acceptable tests before we could harvest again. Clearance took the better part of two months - we suffered the “long” red tide. And the wait delivered a brutal blow to our revenue stream. We scraped by thanks to our oyster farm tours where we served guests competitors’ oysters with a wink and an apology.

Without harvesting, the summer pace slowed. In many ways, it was a relief. Instead of our usual sprint to Labor Day, we took advantage of the quiet time to clean house and get our farm in order. That way we’d be stronger and more productive before the onset of the next pandemic.

I just never imagined the next one – only seven months later - would be on land.


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© 2021 by Abigail S Carroll

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