

Devastated rainforest in Indonesian Borneo. Photo by: Rhett A. Butler.

In 48 years wildlife populations in the tropics, the region that holds the bulk of the world’s biodiversity, have fallen by an alarming 61 percent, according to the most recent update to the Living Planet Index. Produced by the World Wide Fund for Nature (WWF) and the Zoological Society of London (ZSL), the index currently tracks almost 10,000 populations of 2,688 vertebrate species (including mammals, birds, reptiles, amphibians, and fish) in both the tropics and temperate regions.

“Much as a stock market index measures the state of the market by tracking changes in […] a selection of companies, changes in abundance (i.e., the total number of individuals in a given population) across a selection of species can be used as one important indicator of the planet’s ecological condition,” the report reads.

Between 1970 to 2008, species abundance in the tropics fell by 44 percent on land, 62 percent in the oceans, and 70 percent in freshwater environments, culminating in an average loss of 1.25 percent every year since the baseline was set in 1970. Wildlife populations are declining due to a number of large-scale human impacts including ongoing deforestation, habitat degradation, overexploitation for food or medicine, pollution, agricultural, overfishing, invasive species, disease, climate change, dams, mining, and other industrial projects.





Tiger populations have fallen by 70 percent from 1980 to 2008. Today, more tigers live in captivity in the U.S. than in the wild. Photo by: Rhett A. Butler.

The report also examines impacts in particular regions. Wildlife populations in tropical Africa have dropped by 38 percent, by half in the Neotropics (Central and South America) by half, and by 64 percent in the Indo-Pacific (including India, Southeast Asia, Australia, and Pacific Islands). This is perhaps not surprising since the world’s highest deforestation levels are in Southeast Asia.

“These declines reflect large-scale forest and other habitat loss across these realms, driven by logging, growing human populations, and agricultural, industrial and urban developments,” the report reads.

In the Neotropics, recent years have seen amphibians decimated by a fungal disease. The disease, known as chytridiomycosis, is not only cutting populations down but also pushing dozens of species to extinction.

“This report is like a planetary check-up and the results indicate we have a very sick planet. Ignoring this diagnosis will have major implications for humanity. We can restore the planet’s health, but only through addressing the root causes, population growth and over-consumption of resources,” Jonathan Baillie, conservation program director with the Zoological Society of London said in a press release.

Biodiversity provides many services to global society, including pollination, carbon sequestration, food production, soil health, and life-saving medicines among others, although few of these ‘ecosystem services’ are yet recognized by the global market.

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