Today, the Downeast Institute (DEI) hosted us for a tour of their shellfish hatchery and campus. Kyle Pepperman, the hatchery and production manager, gave us a look into how shellfish are raised in this area. He discussed the different needs that various species need, particularly looking at soft shell clams, the focus of our shellfish initiative. One of the most important rooms in the facility is where they grow the algae to feed the shellfish. It has rows and rows of big cylindrical glass tanks of different colors, making the room look somewhat otherworldly and rainbow-esque. This magical looking algae is then dripped through pipes in the floor, down to the tanks and tanks of shellfish below.
DEI uses various different methods to circulate water and feed the young clams, oysters, mussels, and scallops including upwellers and flow through tanks. An important piece of this puzzle is to ensure that the water is warm enough to promote growth and keep the bivalves healthy and happy. This is crucial because without warmth, the process becomes much less efficient, but it is expensive and difficult to heat water. They have solved this issue in part by using the warm waste water they are funneling out of the tanks to heat the cold clean water they are pumping in from the ocean, saving 85% of their energy.
We hope to replicate one of the bucket upwellers that DEI uses to seed clams and oysters in the summer. Theirs sits just outside of their lobster pound, while ours will be indoors. The same concept applies nevertheless: we will pump cold seawater to the clams which will already be full of the algae and nutrients that they need and ensure that there is enough circulation for the clams to survive.
By Sophie Chivers
Shellfish Resilience Intern, Schoodic Institute