Written by Beth Geiger
Native bumble bees are ecosystems’ little heroes. About 85 percent of the world’s flowering plants depend on pollination from animals. These plants and bees have evolved together, shaping ecosystems. For example, different species of bumble bees have different length tongues, suited to pollinating different plants. In wild ecosystems, bumble bees pollinate plants that birds and larger wildlife count on such as wildflowers, nuts and fruit.
Wild bumble bees also soar when it comes to pollinating particular food crops. They use “buzz pollination:” vibrating their wing muscles at high frequencies to loosen pollen in a way that commercially-managed honey bees just can’t match for certain plants including tomatoes, blueberries, and cranberries.
But since the late 1990s, biologists have observed an alarming dive in some wild bee populations. At least four species of Washington’s native bumble bee species are at risk. Morrison bumble bees (Bombus morrisoni), Suckley cuckoo bumble bees (Bombus suckleyi), Western bumble bees (Bombus occidentalis), and Yellow bumble bees (Bombus fervidus) have seen sharp declines in populations and/or ranges.
One problem facing these species is a loss of genetic diversity, which can lead to extinction. Because they live in colonies, bumble bees are naturally susceptible to inbreeding. To sustain diversity they need to connect to other colonies. That’s increasingly tough as native habitat is lost and fragmented. Pesticides, competition and diseases from non-native honeybees, and climate change are other concerns. And if bees fall flat, so will the ecosystems that depend on them. What’s more, if commercial honey bee populations collapse, we’ll need wild bumble bees for many more of our crops.
To help bees, we must create and connect bee-friendly habitat. The Conservancy is doing just that. Wildflowers buzz with bees at our preserves at Moses Coulee/Beezley Hills, Yellow Island, and others. In the past, the Conservancy has also worked with farmers to develop pesticide-free bumble bee habitat in the corners of pivot-point irrigation circles. These actions help keep bumble bees aloft, crops flourishing, and meadows in bloom.