Where are the bees?

According to a new study, since the 1990s, which is 30 years ago, there has been a substantial and alarming drop in the number of wild bee species that are reported in public records.

Researchers checked bee records at the Global Biodiversity Information Facility (GBIF), an online global government-funded biodiversity data collector with data collated from museums, citizen scientists and universities. For the years 2006-2015 there were roughly 25% less bee species reported than during the 1990s. While this does not necessarily mean that one-quarter of wild bee species are extinct, it may mean they are now so rare that scientists have not observed them in nature for about thirty years. This may mean that uncommon species are now rare, while rare species are now locally extinct.

Eduardo Enrique Zattara, adjunct researcher at Argentina’s National Scientific and Technical Research Council (CONICET), is the study author. He realized in 2018 that he would be able to track global population of bee species and long-term trends of bee populations by using this online data. His research team began to explore potential reasons so many bees are missing.

Zattara’s first move was to examine whether the data was artificially low, and perhaps did not accurately reflect the number of bee species. If less people reported bee species, there would be less data entered into the system, according to one hypothesis. Another variation of this theory was that perhaps bee trackers only reported well-known easy-to-identify species.

Upon analysis, none of these potential reasons proved to explain the large drop in the number of reported species, according to Zattara. He believes that the decline in plants and animal populations on the planet, which includes honeybees, shows an actual decline in bee diversity and is most likely the true reason for the drop in reported species numbers.

This unrelated 1:13-minute video by Australian Academy of Science shows some of the biggest disasters bees face:



Kirsten Shoshanna Traynor, who was not involved in the study, is a research associate at the Global Biosocial Complexity Initiative at Arizona State University. She says climate crisis and loss of habitat could play a big role in the declining numbers, as more land is urbanized, and bee habitats are destroyed. This then kills the next generation of bees.

In addition, Zattara says that bees may be forced out of their native climate zones due to climate crises, and they are then exposed to dangerous weather events. Another potential issue is that when foreign bees are introduced to a new area, these invasive bees may kill off the native bees. In respect to this theory, he intends to study a case like this in Patagonia where a foreign bee was introduced, to research how to reverse such damage, to stop or reverse the decline of other wild bees around the world.

Wild bees are responsible for 85% of the pollination of world crops, like such popular foods as nuts, avocados, and apples, according to a study published by Argentina’s CONICET in One Earth Journal last week. Fewer wild bees means much harder if not impossible pollination opportunities for many plants. 

There are over 20,000 bee species known around the world, which implies that about 5,000 bee species are unaccounted for in the past three decades. Some bee families are worse hit than others. For instance, 17% of the second most common Halictid bees have declined compared to 41% of the rare Melittidae bees.

Humanity is responsible for many of the survival issues that bees are having, from deadly pesticides and monocultures to destruction of habitat for urban buildings, and so much more.

As Zattara said, we need to do something for the bees now because they cannot wait. He hopes that by bringing issues surrounding bee diversity to the spotlight, policy makers, scientists and others will take action and get better data to stop the global bee decline.