The first global assessment of pollinators ever has found that extinction pressures on species that facilitate crop production are threatening the world's food supply, with hundreds of billions of dollars' worth of food and agricultural production annually at stake.

In a two-year study handed down last week by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), scientists warn that unless action is taken to curb human activity affecting thousands of species of pollinators, food as we know it is at risk.

"Without pollinators, many of us would no longer be able to enjoy coffee, chocolate, and apples, among many other foods that are part of our daily lives," said Simon Potts, a biodiversity and ecosystems scientist from the University of Reading in the UK, and co-chair of the new assessment.

While people are probably mostly familiar with pollination in the context of bees, the natural process goes far beyond honey production. Over three-quarters of the world's food crops depend at least in part on pollination by insects and other animals.

There are thousands of species that pollinate, with more than 20,000 species of wild bees alone involved in pollination – but also butterflies, flies, moths, wasps, beetles, birds, and bats, among other animals. And a lot of these species are currently threatened with extinction, which could pose a grave problem for the crops they help to produce.

According to the report – which analysed several local and regional studies on pollinator threats – an estimated 16 percent of vertebrate pollinators are threatened with global extinction.

Most insect pollinators have not been assessed at a global level, but separate research projects in localised areas suggest that often more than 40 percent of invertebrate species are threatened with extinction.

"Wild pollinators in certain regions, especially bees and butterflies, are being threatened by a variety of factors," said Sir Robert Watson, vice-chair of the IPBES and former chair of the Intergovernmental Panel on Climate Change. "Their decline is primarily due to changes in land use, intensive agricultural practices and pesticide use, alien invasive species, diseases and pests, and climate change."

Despite the long-running study involving some 80 experts, the scientists say there are still large gaps in our understanding of pollinators and their threatened populations globally, but enough evidence exists to be looking at options on how to safeguard affected species.

The researchers say sustainable agriculture, including practices based on indigenous and local knowledge, would help to ensure more pollinator species don't go extinct.

To achieve this, they recommend maintaining a greater diversity of pollinator habitats; supporting traditional practices that manage habitat patchiness, such as crop rotation; decreasing the use of pesticides; changes to bee husbandry and commercial pollination practices; and public education and awareness campaigns.

A summary of the assessment is available online, and while the report's findings are concerning, hopefully the outlook will galvanise people's efforts to protect pollinator populations while we still have the chance.

Losing pollinator species would be (and is) an ecological tragedy in itself, but the financial risk may be what ultimately forces the agricultural change: the report estimates somewhere between US$235 billion and US$577 billion worth of annual global food production is on the line.

"The growing threat to pollinators, which play an important role in food security, provides another compelling example of how connected people are to our environment, and how deeply entwined our fate is with that of the natural world," said Achim Steiner, executive director of the United Nations Environment Programme (UNEP), in a statement.

"As we work towards food security, it is important to approach the challenge with a consideration of the environmental impacts that drive the issue. Sustainable development, including improving food security for the world's population, necessitates an approach that embraces the environment."