David Attenborough
David Attenborough thinks we should be hopeful for the planet's future. He will be speaking live at the Earth Optimism event on 22 April 2017. John Phillips/Getty Images

The world's top naturalists and conservationists, including David Attenborough, Jane Goodall and Steven Pinker, are speaking in Cambridge this weekend about why we should be hopeful for the planet's biodiversity and environment.

The event will be held on 22 April, marking Earth Day 2017, a celebration of the planet and the environment. The planet is said to be entering a sixth mass extinction due to human activity, Arctic ice is melting like never before and human toxic pollution has been found in the furthest reaches of the oceans. It might seem like a tall order, but there are actually many reasons to be optimistic about nature, wildlife and the environment.

"When we got together and made a list of environmental success stories there were so many, we really had to cut a lot out," Rosie Trevelyan, director of the Tropical Biology Association and chair of council of the Cambridge Conservation Initiative, told IBTimes UK.

"We usually hear a lot of doom and gloom stories about species going extinct."

But some species are making a miraculous recovery. The bittern is a heron-like bird that lives in the Cambridge Fens. It was thought to be virtually extinct in the UK until fenland restorations have led to a boom in the population of bitterns.

Further afield, very encouraging reductions in deforestation of the Amazon should give people some comfort, Trevelyan said.

"Many people grew up worrying about rainforests, and we know in many places they're disappearing. But deforestation in the Amazon has slowed by 80% in 10 years. There really are examples where conservation success has happened, but we don't hear about it so much."

The Earth Optimism event will feature two main strands: stories of hope and a solutions fair. The first strand will feature inspirational talks by celebrities and naturalists.

Sir David Attenborough said in a statement: "While we cannot ignore the threats to nature, there are a growing number of examples of improvements in the health of species and habitats, along with benefits to human well-being, thanks to conservation action. But conservation cannot succeed through experts alone. The decisions that we all make in our day-to-day lives are critical for its success."

Attenborough has previously said that there was "overwhelming reason to be pessimistic" about the Earth's future, but that humans must band together to solve the problems we have caused.

You can watch all the talks from the event live here on 22 April, from 10am BST. Attenborough will be speaking from 17:00 BST.