Why I Believe We Can Rewild Half the Planet by 2050

In 2016, E.O. Wilson published Half-Earth: Our Planet’s Fight for Life, and it changed the trajectory of my thinking permanently. Not because the idea was new to me — anyone who has spent decades watching species blink out of existence understands that we need to protect far more land and sea than we currently do. What Wilson did was give the aspiration a number. Half. Not 17 percent, not 30 percent. Half.

That number terrified people. It still does. But the science behind it is remarkably straightforward: if we protect and restore roughly 50 percent of Earth’s terrestrial and marine environments, focusing on the most biodiverse regions, we can safeguard approximately 85 percent of all species. Drop below that threshold and the extinction curve steepens catastrophically. This isn’t ideology. It’s conservation biology at its most fundamental.

I’ve spent more than three decades in this space — from my first days volunteering at Jersey Zoo as a teenager in 1989, through years of fieldwork, policy battles, and eventually founding CreditNature. And I can tell you that the conversation has shifted more in the last five years than in the previous twenty-five combined.

The economics are finally catching up

For most of my career, conservation was framed as a cost. Protect a forest and you lose the timber revenue. Restore a wetland and you lose the agricultural output. This framing was always intellectually dishonest — it ignored the value of flood mitigation, carbon sequestration, pollination, water filtration, and a thousand other ecosystem services — but it dominated policy discussions for decades.

That era is ending. The Taskforce on Nature-related Financial Disclosures (TNFD) is pushing companies to account for their dependencies on nature. The EU’s Corporate Sustainability Reporting Directive (CSRD) is making nature risk a boardroom issue. And the Global Biodiversity Framework agreed in Montreal set a target of 30 percent protection by 2030 — an interim milestone that, if met, puts Half-Earth within genuine reach.

What excites me most is the emergence of nature credit markets. At CreditNature, we’ve spent years building the measurement infrastructure — the NARIA framework, the Ecosystem Condition Index — that allows nature’s recovery to be quantified, verified, and ultimately traded. When you can measure something credibly, capital follows.

Why I think we’ll get there

I won’t pretend the path is smooth. We face enormous challenges: land rights conflicts, governance failures, the sheer speed of habitat destruction in the tropics. But three things give me genuine confidence.

First, rewilding works. Wherever we’ve given ecosystems space and time, they’ve responded with staggering resilience. Wolves in Yellowstone. Beavers in the Scottish Highlands. Mangrove restoration across Southeast Asia. Nature’s capacity to heal itself, given half a chance, is extraordinary.

Second, the financial architecture is being built right now. Biodiversity credits, natural capital accounting, blended finance structures — these aren’t theoretical anymore. They’re being deployed. The gap between conservation need and available capital is still vast, but it’s narrowing faster than most people realise.

Third, the generational shift is real. I meet young conservationists, ecologists, and entrepreneurs every week who see no contradiction between economic ambition and ecological restoration. They don’t want to choose between prosperity and a living planet. They refuse to.

Wilson didn’t live to see his vision realised. He died in December 2021, at 92, still writing, still pushing. I think about that often. None of us are guaranteed enough time to see the full arc of our work. But we can lay foundations that outlast us.

Half the planet. By 2050. It sounds impossible until you look at the trajectory. Then it starts to look like the only sane option we have left.