There are many more bee species than most people realise – more than 20,000 – and now, we know where to find them. This month, scientists made a giant leap toward protecting bees by mapping the diversity of one of nature’s most important pollinators for the first time.
Bee populations around the world are at risk due to human activities such as pesticide use and climate change. Understanding the distribution of bee species is critical to inform conservation and sustainable land management decisions. If we know which species depend on which ecosystem, we can better predict how they will react to shocks, such as changes in rainfall or farming techniques, and put in place measures to prevent their decline.
Pollinators are the foundation for human health and wellbeing. They sustain populations of wild plants that underpin ecosystem services, allow us to produce crops, ensure food security and support cultural values. The majority of plants rely on pollination by animals and up to $577 billion in annual global crops are at risk from pollinator loss.
Bees do much more than make honey, and there are more bee species than there are mammals and birds combined. They visit more than 90% of the leading crop types and are the top pollinator group in many countries. The United States has the most species of bees, but there are areas in Africa and the Middle East, for example, that have high levels of undiscovered diversity.
Although awareness of the importance of bees has been on the rise in policy circles and the general public our response has not kept up with the threats that they face. In the US, honey bee populations declined by 60% between 1947-2008, while in Europe, 12 wild bee species are critically endangered.
Mapping bee hotspots
Using a comprehensive checklist of bee distribution and almost 6 million public bee records, an international team of researchers pioneered an insight into global patterns of bee diversity. Most plants and animals follow the same pattern, in which there is most biodiversity towards the tropics, and less towards the poles. Bees appear to be an exception to this rule. While there are fewer species towards the poles, there are also fewer near the equator. In areas where bees are less abundant, you see a rise in alternative pollinators such as wasps, cockroaches or moths.
The data of this study show that bees favour deserts and temperate environments over tropical regions. This is because trees provide bees with fewer food sources than low-lying plants and flowers. Additionally, bees do not like it too wet, unlike their ant cousins whose populations peak in tropical regions. As the study suggests, humidity may limit bee distribution due to damage to pollen resources.
This study provides a crucial step in assessing the impact of human activity on bees and tracking the potential decline of bee populations. It is hoped that it will form an important baseline for further research and targeted conservation efforts. The findings will help scientists and governments identify bee hotspots that are in areas of the world at risk from environmental degradation and damaging agricultural practices. The findings could also allow a better understanding of pollination services in analyses of ecosystem services. Equally, this study could be used to predict the effect of climate change on future bee distributions, especially as it impacts rainfall patterns.
Many lower-income countries depend on wild, not domesticated, species of bees for their crops, and research on these is very sparse. When honeybees decline, beekeepers can order more. This is not the case for wild species. Food security for those most vulnerable, therefore, relies on studies such as these that highlight lesser-known species and allow us to safeguard biodiversity and the services that are so central to human prosperity.
Developing solutions for biodiversity
Declining populations of bees and other pollinators are not only a problem for people and governments. Businesses also have a responsibility to help develop solutions. Businesses have a direct impact on pollinator loss through harmful agricultural practices, for example. They also contribute indirectly to the loss of habitats and climate change through greenhouse gas emissions.
Far from requiring purely altruistic motives, however, businesses have an economic incentive to address the issue. The loss of bees will directly affect business revenues in areas such as agriculture, food transportation and healthcare due to the reduction in the availability of crops. Pollinator decline is, therefore, a material risk to business operations and should be accounted for in decision making, with businesses opting for nature-positive models.
Bees are some of the most important pollinators in the world. They ensure we are fed and also allow plants to do their job. If bees were to disappear, it would lead to a domino effect of the loss of plants, crops and, potentially, of entire ecosystems. By understanding the distribution of bee species, we are increasing our odds of successfully protecting such an critical player in natural and human systems. Putting them on the map, along with rhinos, tigers and pandas, lays the foundations for more efficient and effective conservation efforts and enable us to protect the ecosystems on which bees, and we, so desperately depend.