Newly established grassland areas created to replace habitats lost to development can effectively aid wild pollinators such as bees and hoverflies, according to research conducted in the Netherlands. The results appear in the Journal of Applied Ecology.
Scientists at Wageningen University examined these new offset grasslands alongside established ones throughout the country. They observed that the offset sites hosted twice as many wild bees and a greater variety of bee species than the existing grasslands, while hoverfly populations remained similar in both.
Flower species counts were also comparable, though the specific types varied. This indicates that offset areas are not identical substitutes but still supply valuable resources for pollinators.
The evidence suggests that well-designed biodiversity offset locations can match or even exceed existing sites in supporting pollinator diversity, at least initially.
Lead author Klara Leander Oh noted that the work offers strong proof of offsetting as a useful approach for conserving pollinator species, provided the new habitats receive proper planning and ongoing care.
The Netherlands has lost 90 percent of its semi-natural grasslands over the past century, critical areas for pollinators. Policies such as the EU No Net Loss initiative and UK Biodiversity Net Gain aim to stop further declines.
Although the study demonstrates potential success, it examined only sites that were properly created. Variation in management raises questions about overall performance.
Oh added that uncertainty remains about how many required offsets are fully carried out and maintained. Improved documentation and extended monitoring would help confirm their benefits for biodiversity.
Researchers surveyed 20 offset grasslands and 20 reference sites using transect surveys, flower tallies, and vegetation assessments to measure resources and insect numbers.
