This story originally appeared in The Guardian and is part of the Climate Desk collaboration.
The number of wild bee species recorded in an international database on life on earth has fallen by a quarter since 1990, according to a global analysis of bee declines.
Researchers analyzed bee records from museums, universities, and citizen scientists compiled by the Global Biodiversity Information Facility (GBIF), a global, government-funded network that provides open access data on biodiversity.
They noted a sharp decline in bee species that has been recorded since 1990. About 25 percent fewer species were reported between 2006 and 2015 than before the 1990s.
While that doesn't mean these species are extinct, it may indicate that some have become so rare that they are no longer regularly seen in the wild.
"With citizen science and the ability to share data, records are increasing exponentially, but the number of species reported in those records is decreasing," said Eduardo Zattara, lead author and biologist at Universidad Nacional del Comahue and the Argentine National Scientific and Technical Research Council. "It's not a bee disaster yet, but we can say that wild bees are not thriving."
A separate series of scientific studies of global insect declines earlier this month warned that insect abundance was declining 10 to 20 percent every decade, an "absolutely frightening" loss that threatened to "tear apart the tapestry of life."
In the US, a 2020 study found that a shortage of bees in agricultural areas limited the supply of some food crops. In the UK, this month the government allowed farmers to use neonicotinoids on sugar beets, despite the fact that the pesticides that kill bees were banned across the EU in 2018, with UK support.
The new study, published in One Earth magazine, analyzed records from three centuries of collections that include more than 20,000 known species of bees around the world.
It turned out that the decreases were not evenly distributed among the bee families. While records on Halictid bees, the second most common family, have declined 17 percent since the 1990s, records on Melittidae – a much rarer family – have fallen by more than 41 percent.
Scientists have warned that a lack of scientific data on insect decline in tropical countries undermines their understanding of global bee decline, with most of the GBIF records covering North America and Europe.
The study authors acknowledged that the decline in species may, in part, reflect changes in the GBIF's data collection over time or the heterogeneous nature of its data sets.
Zattara said that while her study did not determine the status of individual bee species, it showed a clear global trend with declining biodiversity, which likely indicates a global decline in bees and other pollinators.
"It's about affirming that what is shown locally is happening globally," he said. "And also about the fact that much better security is achieved when more data is shared with public databases."
He warned that waiting for more data to confirm the bee type more accurately and other pollinator declines may be too late to save them.
“Something is happening to the bees and something has to be done. We can't wait to be absolutely certain because we rarely get there in science, ”he said. “The next step is to get policymakers to act while we still have time. The bees cannot wait. "
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