TOP SHELL OYSTER FARM
MARTHA'S VINEYARD, MA
Every great journey begins with a challenge, and for Maddie Henson and Liam Cosgrove, founders of Top Shell, those challenges were the tides themselves. Nestled off Martha’s Vineyard, their open-ocean oyster farm began as an ocean of obstacles, from losing their first oyster cage to navigating the unpredictable waters of entrepreneurship. But what started with struggles has transformed into a thriving business that blends passion, grit, and environmental stewardship.
Their journey, rooted in ambition, sustainability, and a deep connection to their community, is redefining the future of aquaculture—offering inspiration not only to budding entrepreneurs but to anyone passionate about making a positive impact on the world.
MADDIE & LIAM
Behind Top Shell are Maddie and Liam, a dynamic duo whose complementary skills keep the farm afloat—literally and figuratively. Liam, the boat captain and farm manager, is the hands-on problem solver. Whether he’s maintaining the boat, hauling cages, or shucking hundreds of oysters at a raw bar, his role is pivotal in ensuring the farm runs smoothly. His background and love for the ocean are reflected in every aspect of his work.
Maddie, on the other hand, manages the business side of things, juggling everything from marketing to billing. Yet, the partnership goes beyond traditional roles. On any given day, you might find Maddie piloting the boat while Liam tackles spreadsheets. Their shared adaptability and teamwork make Top Shell a true partnership—a blend of creativity, resourcefulness, and shared vision.
At the heart of Top Shell is Martha's Vineyard, their home and the foundation of their mission. Liam and Maddie are deeply connected to the island’s culture, and for them, the farm is more than just a business—it's a way to bring the community together. They are passionate about promoting sustainable, local food sources, using their oysters to support environmental sustainability. Through their work, they aim to inspire others to embrace sustainable food practices that are better for both the environment and the community. To them, it’s not just about oysters—it’s about fostering a sense of shared purpose, unity, and environmental stewardship, one shell at a time.
A NEW PERSPECTIVE
Top Shell sets itself apart as a pioneer in sustainable aquaculture on Martha’s Vineyard. Located one mile off the coast of Edgartown, it is the only open-ocean oyster farm in town, a distinction that gives its oysters a unique edge. The farm’s location in the open ocean—with strong tides and a rocky seabed—creates the perfect environment for cultivating oysters with a briny, slightly sweet flavor that is unmatched by oysters grown in calmer ponds or bays. This distinct flavor profile is a direct result of the farm’s environment, giving Top Shell’s oysters a taste that reflects the spirit of the sea.
Beyond the flavor, Top Shell stands out for its innovative approach and youthful energy. As one of the few farms on the Vineyard owned and operated by a duo in their 20s, Maddie and Liam bring fresh perspectives to an industry traditionally shaped by seasoned farmers. Their open-ocean methods, combined with a commitment to sustainability, have redefined what it means to be a modern oyster farm. Additionally, as a women-owned business, Top Shell is breaking barriers and inspiring others to embrace innovation in aquaculture. For Maddie and Liam, Top Shell isn’t just a farm—it’s a reflection of their values, a dedication to the ocean, and a vision for a more sustainable future.
A BRIGHT FUTURE
As they look to the future, Maddie and Liam are not just focused on growing their business—they’re driven by a vision to make a lasting impact. Their plans to triple their harvest and expand their direct sales are just the beginning. With a dream boat on the horizon and a commitment to sustainable aquaculture, they aim to create a farm-to-table experience that brings their community closer to the ocean’s bounty. Beyond expanding their reach, Maddie and Liam are actively exploring collaborations with universities and sustainable seafood advocates to push the boundaries of innovation in aquaculture.
For Maddie and Liam, the journey is about more than just growing their business—it’s about creating something that last’s. They’re committed to making an impact that not only supports the ocean but also inspires others to pursue their passions with the same energy and purpose that fuels their work. Their journey is a testament to the power of collaboration, resilience, and the unwavering belief that business can be a force for good.
Working with Maddie and Liam has been nothing short of inspiring. Their passion for the ocean, commitment to sustainability, and determination to create something meaningful shine through in everything they do. As the world continues to evolve and uncertain times lay ahead, we need more people like Maddie and Liam—those who embrace risk, push boundaries, and, above all, collaborate to build a brighter future.
OYSTER FARMING 101
Oyster farming is a unique intersection of agriculture and environmental conservation, where cultivating a crop directly benefits the surrounding ecosystem. Unlike traditional farming, oysters require no feed, freshwater, or chemical inputs to thrive. Instead, they rely on the natural nutrients found in their aquatic environment. This makes oyster farming one of the most sustainable methods of producing protein, with a minimal ecological footprint. For coastal communities, oyster farms also provide economic benefits, creating jobs and supporting local industries while promoting a deeper connection to marine life.
In addition to being a sustainable food source, oyster farming plays a crucial role in maintaining ocean health. Oysters are nature’s water filters, capable of filtering up to 50 gallons of water per day. This process removes nitrogen and other excess nutrients from the water, preventing harmful algae blooms and improving water clarity. Furthermore, oyster beds serve as habitats for a variety of marine species, from small fish to crabs, fostering biodiversity. Oyster farming is not just about growing a product—it’s about giving back to the ocean, ensuring its vitality for future generations.
Dropping Anchor in Uncharted Waters
Reflecting on the early years of building their oyster farm, Maddie describes the challenges they faced as both relentless and rewarding, shaping the foundation of their business today:
“Those first few years were an adventure, to say the least! Although Liam brought a few years of oyster farming experience to the table, starting our own farm was a whole new challenge. Just getting the permits took over eight months—before we’d even touched the water. From there, it was a steep learning curve (and sometimes a slippery slope).
We dropped our entire life savings into the ocean—literally. Our boat broke down regularly, the waves at our open ocean site were relentless at times, and our first winch fell apart the first time we tried to use it. Then there was the time we dropped our first cage and lost it for a month. By the time we finally found it, it felt like discovering buried treasure.
And that’s just the farming side of things! On top of that, we faced the usual challenges of starting a new business: navigating taxes, figuring out bookkeeping, and learning how to work together as a team under some seriously high-pressure conditions. Every day felt like a crash course in business management and survival.
We also both worked multiple other jobs during those first few years, typically working 14+ hour days to keep the farm afloat. Those early days were tough, but they were also full of grit, determination, and lessons we’ll never forget.”
