Science has for the first time put a dollar value on the world's national parks and nature reserves

A mule train at Grand Canyon National Park, Arizona. Sean Gallup/Getty Images

The world’s national parks and reserves receive around eight billion visits every year, according to the first international study into tourism in protected areas.

The study, published in the journal PLOS Biology, is the first global-scale attempt to answer the question of how many visits protected areas receive and what they might be worth in terms of tourist dollars.

The UK and the US and researchers say visits could generate as much as $US600 billion of tourism expenditure a year, a good return on the $US10 billion spent on the protected areas each year.

“It’s fantastic that people visit protected areas so often, and are getting so much from experiencing wild nature – it’s clearly important to people and we should celebrate that,” said lead author Professor Andrew Balmford, from Cambridge University’s Department of Zoology.

“These pieces of the world provide us with untold benefits: from stabilising the global climate and regulating water flows to protecting untold numbers of species. Now we’ve shown that through tourism nature reserves contribute in a big way to the global economy- yet many are being degraded through encroachment and illegal harvesting, and some are being lost altogether. It’s time that governments invested properly in protected areas.”

The estimates based on limited data and are conservative. Visit rates are likely to be higher than eight billion a year.

The calculations are for more than 140,000 protected areas.

Visit rates were highest in North America, where protected areas receive a combined total of more than three billion visits a year, and lowest in Africa, where many countries have less than 100,000 protected area visits annually.

The Golden Gate National Recreation Area near San Francisco had the highest recorded visit rate in the database with an annual average of 13.7 million visits, closely followed by the UK’s Lake District and Peak District National Parks, with 10.5 million and 10.1 million.

Tanzania’s Serengeti National Park got an annual average during the study period of 148,000 visits.

Balmford says to compare the costs of looking after the protected areas — $US10 billion — with computing giant Apple’s record profits of $US18 billion a quarter.

“Stopping the unfolding extinction crisis is not unaffordable,” he says. “Three months of Apple profits could go a long way to securing the future of nature. Humanity doesn’t need electronic communication to survive. But we do need the rest of the planet.”

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