Human Activities Threaten Up to 1 Million Species With Extinction

Written by Marian Starkey | Published: May 7, 2019

The UN just presented a teaser of its most comprehensive report on biodiversity since 2005, and the central point it makes is devastating: Up to a million plant and animal species are threatened with extinction, and human activity is to blame. Changes in land and sea use, direct species exploitation, climate change, pollution, and the introduction of invasive species are the primary direct causes. The Summary for Policymakers of the forthcoming “Global Assessment Report on Biodiversity and Ecosystem Services” was prepared by IPBES (the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services). It’s the result of a three-year review of 15,000 scientific and government sources, written by 145 experts from 50 countries, and aided by 310 additional expert contributors. It is a truly global effort, and includes voices from indigenous people and local communities—a first for an assessment of this kind.

Large-scale intergovernmental reports on environmental crises often ignore human population growth as an exacerbating factor—at least in any meaningful way. This new report, presented yesterday at the UNESCO world headquarters in Paris, is different. In addition to reiterating at several different points that population growth is a primary cause of human-driven habitat loss and species extinction, it goes so far as to suggest that slower population growth could be part of the solution to saving species—which are disappearing tens to hundreds of times faster than the average rate over the past 10 million years.

The report outlines the various types of land-use changes that humans are responsible for inflicting on wildlife habitats. It identifies conversion to agricultural land as the biggest culprit in driving habitat loss—more than one-third of land on Earth is currently used for crops and grazing. Urbanization and infrastructure development also contribute to land-use changes. These three human interventions—each amplified by population growth—destroy forests, wetlands, and grasslands, which are home to many of the world’s terrestrial species. In all, three-quarters of the terrestrial environment has been “severely altered” by human activities.

The forest cover of today is only 68% what it was during pre-industrial times. The outlook is even worse for wetlands: 85% of those present in 1700 were gone by 2000.

The authors note that the human population has doubled in the past 50 years, and they acknowledge that future population growth will continue to wreak havoc on wildlife:

“The negative trends in biodiversity and ecosystem functions are projected to continue or worsen in many future scenarios in response to indirect drivers such as rapid human population growth, unsustainable production and consumption and associated technological development. In contrast, scenarios and pathways that explore the effects of a low-to-moderate population growth, and transformative changes in production and consumption of energy, food, feed, fibre and water, sustainable use, equitable sharing of the benefits arising from use and nature-friendly climate adaptation and mitigation, will better support the achievement of future societal and environmental objectives.”

Humans have already caused the extinction of at least 680 vertebrate species since the 16th century. We are on track to lose many more species in the coming decades, if drastic proactive measures aren’t taken now:

  • 40% of amphibian species are threatened with extinction
  • 33% of reef-forming corals, sharks, and marine mammals are threatened with extinction
  • 10% of insect species are threatened with extinction
  • 33% of marine fish stocks are being harvested at unsustainable levels

The report points out that saving nature isn’t only important for the survival of threatened species—it’s also necessary for human survival. Insects pollinate 75% of the crops we depend on for food, so their extinction harms farmers’ ability to grow enough food for our burgeoning population—11% of which is already undernourished. Overfishing has severe implications for the 3 billion people who rely on seafood as their primary source of protein. Many medicines, including 70% of cancer drugs, are developed using products found in nature. And about 4 billion people rely primarily on natural medicines.

The report provides policy prescriptions including “lowering total consumption and waste, including by addressing both population growth and per capita consumption differently in different contexts.” Indeed, in wealthy nations, we have no choice but to curb our conspicuous consumption. And in poor and middle-income nations, where standards of living are rising, as they must, consumption will continue to increase. The only way to sustainably accommodate this increase in consumption is for the population to stabilize. An estimated 214 million women in the developing world want to avoid pregnancy, but have an unmet need for family planning. Investing in this basic public health intervention is a necessary component to any large-scale ecosystem protection strategy.

The full 1,500-page report is expected to be published later this year.

News coverage of the report’s release:

The Washington Post

The New York Times

National Geographic