Intensive agriculture could drive loss of bees and other tropical pollinators

Pollinators in the tropics are less likely to thrive in intensive croplands, finds a new study led by UCL researchers suggesting bees and butterflies are at risk of major losses. Across the globe, lower levels of land use intensity are good for pollinators, finds the new Nature Communications paper which shows the importance of sustainable land management in cities and agricultural regions. As insect pollinators were found to be more than 70% less abundant in areas with intensive cropland, compared to wild sites, the researchers say that more sustainable agricultural practices are needed to avert widespread losses of bees and other valuable insects. Lead author, PhD candidate Joe Millard (UCL Centre for Biodiversity & Environment Research, UCL Biosciences and Institute of Zoology, ZSL), said: "Pollinating species are thought to be in decline globally due to combined pressures of habitat loss and climate change. Here, we found that pollinators in tropical regions are the most likely to decline as croplands continue to expand and intensify, and as animals in the tropics are also particularly vulnerable to the impacts of climate change.*" The researchers modelled the effect of land-use type and intensity on global pollinator biodiversity, using a database covering 303 studies, 12,170 sites (primarily across North and South America, Europe, and Africa), and 4,502 pollinating species, including insects, birds and bats. The researchers found that overall, low levels of land use intensity appear to have beneficial effects for pollinators, even compared to natural vegetation, while increasing intensity of different land uses was associated with reductions in species richness (the number of different species) and total abundance.