The population sizes of mammals, fish, birds, reptiles, and amphibians have declined an average of 68% between 1970 and 2016, according to World Wildlife Fund’s (WWF) Living Planet Report 2020, a biannual assessment of wildlife. Latin America and the Caribbean were the most affected, with an average decline of 94%.

The report pointed to humanity as the underlying cause of the deterioration of nature and the decline in the wildlife population. The increase in consumption, population, trade and urbanization in the last 50 years means we now use more of Earth’s resources that can be replenished. And this has a tremendous impact on biodiversity.

“This report reminds us that we destroy the planet at our peril—because it is our home. As humanity’s footprint expands into once-wild places, we’re devastating species populations. But we’re also exacerbating climate change and increasing the risk of zoonotic diseases,” said WWF CEO Carter Roberts in a statement.

The report measures the size of vertebrate populations. This is different from identifying threatened or extinct species, which may indicate little about the overall health of an ecosystem and, consequently, the natural services provided to people. The finding shows nations haven’t been doing their homework to protect biodiversity.

Freshwater biodiversity is declining much faster than that in our oceans or forests. The 3,741 monitored populations in the Freshwater Living Planet Index have declined by an average of 84%, equivalent to 4% per year since 1970. Most of the declines are seen in freshwater amphibians, reptiles and fishes.

The main direct driver for biodiversity loss is land-use change, according to the report, specifically the conversion of native habitats such as forest and grassland into agricultural systems. Climate change isn’t the main driver yet but WWF anticipates it will become as important as the other drivers in the coming decades.

Despite nature is being destroyed at a whopping rate, the declining trends could be flattened and reversed with urgent and unprecedented actions, the report’s authors argued. This includes changing food production and consumption, tackling climate change, and investing in actions that truly conserve, protect, and restore nature.

But that’s not all. WWF also highlighted the importance of changing our economic system in order to reflect the natural capital that supports our economic prosperity. In sum, it’s a call to global leaders to treat biodiversity conservation as an investment to preserve human health, wealth and security.

“While the trends are alarming, there is reason to remain optimistic,” said WWF Global Chief Scientist Rebecca Shaw in a statement. “Young generations are becoming acutely aware of the link between planetary health and their own futures, and they are demanding action from our leaders. We must support them in their fight for a just and sustainable planet.”