The presence of bees buzzing around flowers in the United States is a common sight, with honeybees from Europe being the most recognizable. However, there are thousands of less familiar, native bee species that also play a crucial role in pollinating plants, including many agricultural crops. Despite this essential function, these native bee populations appear to be on the decline, with experts suggesting multiple factors but no definitive reason. A new study published in Nature Sustainability suggests that pesticide use may be a significant contributor to the decline in wild bee populations, with some species seeing a 56% decrease in areas with high pesticide use.
The study, conducted by Laura Melissa Guzman of the USC Dornsife College of Letters, Arts and Sciences, and an international team of researchers, examined museum records, ecological surveys, and community science data from 1996 to 2015 across the United States. Through advanced computational methods, they analyzed over 200,000 observations of more than 1,000 bee species to assess the frequency of sightings in different locations. Additionally, they considered data from U.S. Geological Survey and Pesticide National Synthesis Project to correlate land use, pesticide use, honeybee colonies, and agricultural crops with wild bee sightings over the past two to three decades. The results showed a strong correlation between pesticide use and a decrease in wild bee sightings, highlighting the impact of pesticides on these vital pollinators.
The researchers found that alternative pest control methods, such as integrated pest management, are essential for protecting wild bee populations. Integrated pest management involves using natural predators, modifying practices to reduce pest establishment, and using physical means to control pests, with pesticides as a last resort. The team also emphasized the need for more localized, long-term studies to understand how chemicals affect bees over extended periods and under natural conditions. These findings highlight the importance of collecting more data and conducting further research to develop strategies that benefit all pollinators, including wild bees.
The study also revealed that current ecological risk assessments (ERAs) underestimate the impact of pesticides on wild bees and other pollinators. ERAs typically focus on the effects of pesticides on honeybees in lab studies and extrapolate those findings to native bee species. However, the research demonstrated that many wild bees are even more sensitive to pesticides than honeybees, leading to potential lethal effects. The researchers called for regulatory agencies, scientists, and policymakers to rethink current ERA methods to better protect all pollinators, including wild bees. More data and analysis on the long-term effects of pesticides are needed to guide conservation efforts and preserve bee populations for future generations.
In conclusion, the decline in wild bee populations due to pesticide use poses a significant threat to ecosystems, agriculture, and food security. The study’s findings underscore the urgent need for alternative pest management strategies and more comprehensive long-term research to protect these essential pollinators. By reevaluating current practices and considering the unique responses of different bee species to pesticide exposure, researchers hope to develop more effective ways to safeguard wild bee populations and promote biodiversity. With further study and collaborative efforts, there is hope for creating a healthier environment for all pollinators, including native wild bees.
