Thursday, October 08, 2020

Commercial bee colonies keep declining, USDA data show; they and other pollinators face serious risks, says new study

"A collection of threats — habitat loss, pathogens, pesticides, pollution and poor nutrition — have led to widespread decline in bee health and pollinator populations, Jodi Helmer reports for The Revelator, a newsroom of the Center for Biological Diversity, a left-leaning nonprofit. "The threats add up: The number of commercial honeybee colonies declined by more than quarter million between April and June 2020, according to the latest data from the U.S. Department of Agriculture. Native bees are at risk, too, with one in four native species in North America at risk of extinction."

Climate change has worsened one threat: a single-cell fungal pathogen called Nosema. The fungus "reproduces in the gut, where it ruptures, spreads out and then infects the cells of the digestive tracts. It leads to lethargy, reduced foraging ability, poor sense of direction and, often, death," Helmer reports. The fungus was once seasonal, killed off by the winter cold. But too many too-warm winters have helped it survive in colonies and spread.

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