The American rusty patched bumble bee (Bombus affinis) has made its way onto the endangered species list. The US Fish and Wildlife Services has suggested a number of reasons for the sharp decline in rusty patched bumble bee numbers, including a vulnerability to pesticides.

Commonly used pesticides on farms and in urban areas can have a lethal toxic effect on rusty patched bumble bees, which may be one of the contributing factors to the 90% decline in population the US has seen since the 1970s. These bees are particularly susceptible to pesticides as not only are they ground nesters, toxins can be directly absorbed through their exoskeleton and via contaminated nectar or pollen.

Other factors listed include habitat loss and degradation, intensive farming, disease and climate change, however, this is the first case of a wild bee species being listed as endangered with a specific mention of pesticides.

Bumblebees, as distinguished from domesticated honeybees, are essential pollinators of wildflowers and about a third of all US crops, from blueberries to tomatoes, according to the Xerces Society for Invertebrate Conservation, which petitioned the Government for protection of the insect.

Pollination services furnished by various insects in the United States, mostly by bees, have been valued at an estimated $3bn each year.

Scott Johnstone
Communications Officer

16 March 2017  |  PPC86