Land hermit crabs are now extremely rare in Bermuda. To see one is a delight — the heavy white shell bumbling through the grass atop strong red legs. These slow-moving invertebrates are iconic symbols of the coastal ecosystem that makes up so much of Bermuda — its beauty and its fragility.

The land hermit crab story is intertwined with the West Indian top shell story. These large molluscs were extirpated from Bermuda by early settlers who harvested them for food. Hermit crabs declined with the decline of top shells because they need to collect shells from the surrounding environment to protect their soft bodies. West Indian top shells are the only shells available in Bermuda that are large enough to protect an adult hermit crab. For a while the crabs were able to get by using the few remaining fossilised top shells, but eventually these ran out.

It got to a point where some hermit crabs were using trash such as plastic containers and glass bottles to protect themselves. Eventually, they simply faded from the ecosystem. Their way of life was no longer possible.

Top shells were reintroduced to Bermuda in 1982, with protected status, and have since spread around the island, meaning that land hermit crabs once again have access to the shells they need to survive.

Hermit crabs themselves have been protected in Bermuda since 2012. However, anecdotally, their recovery has been extremely slow. I remember seeing a few hermit crabs at Devonshire Bay as a child, then none at all for most of my life. However, in the past two years, I have had the fortune of about half-a-dozen hermit crab sightings around Cooper’s Island. There was once a time when these creatures were so numerous that Bermudians would take them home as pets.

Hermit crabs are a reminder of the connection between land and sea, between us and the ocean. While hermit crabs live most of their lives on land, they release their eggs into the ocean — they start their lives as free-floating larvae, scintillating through the planktonic soup of the high seas. With great determination, they float their way back to the shores of Bermuda, from seas thousands of metres deep, to shallows, and crawl out of the water to begin the second part of their life in Bermuda’s coastal forests.

Land hermit crabs experience ocean wandering at the most extreme level, and the feeling of grass beneath their feet. They can go from the open ocean to climbing trees within one lifetime. To protect them means protecting varied ecosystems across their highly migratory life cycle.

Bermuda’s waters are full of stories like this — of species with life cycles of unimaginable complexity. These stories add up to create Bermuda’s greatest natural resource: the ocean, which shapes our culture and way of life.

We have always been an island of sailors and fishermen. Even our maps showed it: in the 1600s, properties were split up into thin slivers, with access to both North and South shores, so that in a boat you could reach either end of the island in any wind direction. Sailing dinghies were a main mode of transport, and a main avenue to food security.

The ocean is our tourism product. People come to Bermuda for its beautiful beaches and pristine coral reefs, from casual sunbathers to scuba divers. The beauty of the island along with our friendly tax structure also attracts international businesses who want to operate and hold meetings here. The ocean is our protector, our playground, our food store, a landscape for sailors, charter boats, divers and fishermen, and a source of spirituality and beauty.

Without the ocean, we have nothing. Bermuda has received the gifts of the ocean for a long time, but we are overdue in taking on the responsibilities that come with accepting those gifts — protecting the ocean so that it can keep providing for us.

Our small platform experiences pressures in an exponential way — it does not take much to tip the scale. Our populations of predatory fish have been critically low for years. Sharks are almost non-existent, but they used to pup in Bermuda’s waters. Populations of land crabs and land hermit crabs have dramatically declined. The fish we catch are smaller and fewer— we are even seeing the switch to fish for species that were once considered “trash” because of the changes we are experiencing.

This reality is not the fault of any one person or any one stakeholder group; it is the result of many choices over a long period of time, over an ecosystem that is more complex and interconnected than we know.

We must make choices now to turn the tide and keep our oceans healthy. To preserve our maritime traditions by preserving the ocean. To safeguard our own future. And to acknowledge the inherent right of this incredible ecosystem to exist and to thrive.

What if we dreamt not of a “good enough” ecosystem, but of a “blue sky” ecosystem? One that is resilient and diverse, able to accommodate species and interactions that I have never had the privilege to behold in my lifetime. Could Bermuda host nesting turtles as we did in the early days of colonisation before they were over-harvested? Could we create a future where land crabs are the ecosystem engineers they deserve to be? For species of grouper that have not been seen for years to form spawning aggregations? For sharks to be the marker of a healthy system, and not so rare that one sighting makes the news?

Marine-protected areas are some of the most effective tools we have to take a holistic approach to conserving a whole ecosystem, while taking into account both ecosystem and human needs. Bermuda has an opportunity to protect our ocean now — we have a robust and stakeholder led plan to protect the waters within our exclusive economic zone, from nearshore to offshore, in the Blue Prosperity Plan, and we have been a consistent champion in the stewardship of the Sargasso Sea through the Sargasso Sea Commission, with exciting upcoming opportunities to legally protect it under the Biodiversity Beyond National Jurisdiction, or BBNJ, agreement.

The distinction between areas of the ocean contained within exclusive economic zones and areas beyond national jurisdiction is a legal one, dreamt up by humans. To effectively protect our ocean, we must do it in a holistic way that acknowledges the highly migratory lifestyles of many of the species that live there — such as the hermit crab, and also the spiny lobster, the wahoo, the turtle, the humpback whale and many more.

Protecting the complex and interconnected ocean ecosystems around Bermuda, from our coastline out into the high seas, is not just about protecting biodiversity, but about protecting ourselves. Our maritime traditions, our way of life, our liveable climate.

The UNEP recently released a report called Limiting Overshoot, saying that the goal of limiting global warming to 1.5C is now out of reach — but that every fraction of a degree matters. It is a call to redouble our efforts. We must do everything we can to limit warming, because it will mean fewer heatwaves that make summers unlivable, fewer deadly hurricanes that destroy our infrastructure, less risk of global food crises, disease and warfare, more chance for low-lying islands to escape being swallowed up by rising sea levels, fewer opportunities to create climate refugees. We need to make changes now, in the short term, to assure the long-term future of our environment.

Right now Bermuda’s best-developed tool to mitigate the effects of climate change and biodiversity loss, and to protect our way of life, is to conserve the ocean — the plans exist and we have the intelligence and compassion to execute them; it’s just a matter of “choosing our hard”.

• Fae Sapsford runs a science communications Instagram account, @Sargassogirl, with the mission to inspire people to care about and protect the ocean