Additionally, there's concern over the widespread use of neonicotinoid insecticides within the species' range. These insecticides have been implicated in declines of other bee species and were introduced around the time that the rusty patched bumble bee entered its downward spiral. The USFWS finding also concluded that problems such as habitat loss and fragmentation and climate change may also be contributory factors.
The Xerces Society notes that the species is an important pollinator, not only of prairie wildflowers but also of cranberries, blueberries, apples, alfalfa and other crops. "Native pollinators in the U.S. provide essential pollination services to agriculture which are valued at more than $9 billion annually," said Eric Lee-Mäder, co-director of the organization's pollinator program.
The rusty patched bumble bee is already listed as critically endangered on the IUCN Red List of Endangered Species, and the USFWS action comes in response to a 2013 petition from the Xerces Society and a lawsuit the following year filed by the society and the Natural Resources Defense Council (NRDC).
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"This decision comes not a moment too soon," said Rebecca Riley, senior attorney with NRDC. "Bee populations -- including thousands of species of wild bees -- are in crisis across the country, and the rusty patched bumble bee is one of the most troubling examples. (This) decision is a critical step forward. If finalized, the endangered species protections will improve the health of our ecosystem as well as the security of our national food supply."
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