bees are perhaps Earth’s most essential pollinators. As they hop from flower to flower, these golden insects not only suck up sweet nectar, but also transfer pollen between plants – a crucial process that aids in plant reproduction. But as the climate crisis accelerates, insects like bees are in grave danger as global warming threatens their habitats and food sources.
However, some bees are also adapting in new and perhaps unexpected ways to warmer climates, according to research published Wednesday in the journal Proceedings of the Royal Society B, potentially impacting these crucial pollination services.
What’s new – The scientists have identified three important changes on bee characteristics – such as diet and body size – as a result of warmer temperatures and drier climates in mountainous climates.
First, the researchers found that the relative abundance – which refers to the distribution of certain bees relative to the larger bee community – of larger bees decreased, while the abundance of smaller bees increased.
Second, bees that tend to nest in holes or cavities – like the bumblebee – fared worse in warmer temperatures compared to bees that make their homes in the ground.
Finally, the researchers found that climate change also affected diet in a surprising way: bees with a more restricted and specialized diet appeared to benefit from less rainfall as their relative abundance increased. On the other hand, generalist bee species with a wider diet range did not benefit from the drier environment, and their relative abundance decreased compared to specialist bees.
Overall, these findings suggest that global warming will alter important features in bee communities, especially in mountainous climates.
“Our findings indicate that the bee community is likely to shift to smaller-bodied bees and solitary bees, ground-nesting bees, and bees with narrower diets,” Gabriella L. Pardee, lead author of the study and a postdoctoral researcher at the University of Texas at Austin says inverse.
Why does it matter – Most bee studies focus on the well-known and highly social bumblebee, but few studies focus on the 20,000 other solitary bees. bee species, limiting our understanding of the impacts of climate change on bees. The study calls this lack of data “worrying” given how the environment plays a “key role” in bee flower pollination.
As bees help plants reproduce, humans need to understand the full impact of climate change on the estimated 20,000 bee species, otherwise our very future could be at stake. While previous research has found declining bee populations and reduced habitats as a result of climate change, it is possible that other bees are unaffected or may even benefit from climate change.
“Bees vary greatly in their foraging behavior and flower preferences across species, so by focusing only on bees, we cannot fully understand how pollination services will change under climate change,” says Pardee.
Bumblebees are the main pollinators in many ecosystems. It’s possible that the increase in smaller bees — as seen in the study — could offset the decline in bee pollination, but that kind of speculation is outside the scope of research, according to Pardee.
How they made the discovery – To understand how climate change affects bees, the researchers went to the Rocky Mountains. Mountain systems are beneficial for studying climate change because their weather patterns change at a greater rate than in other ecosystems, according to the study.
Over an eight-year period, scientists collected bees every two weeks during the flowering season, using their collection to study the impact of climate change on important bee traits such as body size, nesting habits and diet. The researchers monitored the population of at least 154 bee species during this period.
“We found that bees exhibit differences in how well they will respond to climate change based on their life history traits, which are physical traits or behaviors that affect growth, survival and reproduction,” says Pardee.
What is the next – The researchers hope their findings serve as a wake-up call to protect bees. One of the best ways to do this: restore habitats for pollinators like bees.
“Planting a wide variety of drought- or heat-tolerant native plants would provide essential food and nesting resources for bees as temperatures continue to rise,” says Pardee.
Going one step further, Pardee suggests that we need to ensure interconnected habitats so bees can safely venture into “better suited” environments as extreme weather events become more frequent.
“I hope this study highlights the need to promote bee diversity so that we can maximize pollination services in a warming world,” says Pardee.