Each week, Prospect asks a range of experts, as well as our readers, to come up with answers to the questions defining the political agenda.

On Tuesday, the World Wildlife Fund (WWF) released the latest version of its Living Planet Report, which found that the number of mammals, birds, reptiles, amphibians and fish in the world has dropped by more than half since 1970. It's a sobering statistic, which reminds us that, in addition to tackling the more high-profile problem of climate change, we need to act fast if we are to stop the world's animal population dying out.

Don't lose hope

Hope is a potent catalyst. And I would submit that we cannot equip ourselves to face the climate crisis without it. There is such a thing as too late. But while our failure to adequately guard against ecological destruction fills me with frustration, my hope for change remains my driving force: urgent and raging. In addressing how we feel about our planet’s future, we connect science with people. Rachel Carson’s 60s work Silent Spring made the environment compelling—and dramatically impacted public feeling on the issues. We must collaborate too—with politics embracing the growth of grassroots democracy and non-violent direct action. A better world is possible. And in my book, that’s worth a fight. Caroline Lucas, Green party MP for Brighton Pavilion

Fight climate change

Every day we see increased symptoms of climate change. Extreme heat, flooding and wildfires are all on the rise—all negatively straining the natural world. We must protect our biodiversity by working to solve the climate crisis. It is my hope that the UN climate talks in Paris in December 2015 will be a critical step in addressing this global emergency. It is time for governments to make the commitments necessary to reduce global emissions and arrest climate change. Citizens worldwide must demand that their government leaders take urgent action to preserve our future. Ken Berlin, President and CEO of the Climate Reality Project

Reform the economy

The good news is that we’ve known the answer for years: stop using fossil fuels. We know how to do that too: a global carbon market, and a carbon tax, paired with massive public investments in green energy. Tragically this knowledge hasn’t led to action, at least not at the pace required to prevent a dire transformation of our climate. It’s difficult not to be persuaded by the argument, advanced by Naomi Klein among others, that our economic system, which demands perpetual growth, is incompatible with environmental stewardship, which demands that we severely reduce our extraction of natural resources. We should do everything we can to mitigate the coming catastrophe. But it’s time to ask a new question: How are we going to adapt? Nathaniel Rich, Novelist

Better conservationism

For me the next step is for the conservation establishment to ask a question it has not faced in modern times, namely “are we performing as well as we could given the assets available to us?” Our international conservation institutions were designed 40 years ago and have expanded with weak oversight. We need to ask if they are still fit for purpose. The Living Planet Report proposes a common vision and notes the need to “change our course.” But what is the imagined institutional design for conservation from 2030 onwards, and who should decide? For me the next step is for conservation governing boards to consider such questions in conjunction with their public constituencies. Paul Jepson, Course Director of the MSc in Biodiversity, Conservation and Management at University of Oxford

Politicians must change

Wild animals don't have votes. In all countries vested interests—mining, logging, multi-national agriculture, roadbuilders—encourage politicians and the media to cast environmentalists as anti-development, and therefore anti-people. The first step towards saving the natural world is for politicians to understand that protecting wildlife and its habitat protects us, too. “Economy” and “ecology” should mean the same: wise “governing” of the oikos, the home. Instead they are perceived as conflicting. In the name of development, for example, India’s new government is dismantling the excellent laws by which India protected wildlife. But the once-sacrosanct forests also protect the water on which India’s humans depend. We are a tragically short-termist species. Ruth Padel, Poet and Conservationalist

This week's Big Question is edited by Josh Lowe and Jeremy Gordon

Reader responses

@prospect_uk change our politics - alas all our parties (inc. Greens) are stuck with dependence on growth & therefore colonisation of nature

— Ben Cobley (@bencobley) October 3, 2014