Franklin’s Bumble Bee – Oregon Conservation Strategy

Overview

Species Common Name Franklin's Bumble Bee
Species Scientific Name Bombus franklini
Federal Listing Status Species of Concern

Ecoregions

Klamath Mountains

The Klamath Mountains ecoregion covers much of southwestern Oregon, including the Umpqua Mountains, Siskiyou Mountains, and interior valleys and foothills between these and the Cascade Range. The Rogue watershed has the largest population of any coastal watershed in Oregon (Jackson County, Josephine County, and a portion of Curry County). Several popular and scenic rivers run …

West Cascades

The West Cascades ecoregion extends from east of the Cascade Mountains summit to the foothills of the Willamette, Umpqua, and Rogue Valleys, and spans the entire length of the state of Oregon. It is largely dominated by conifer forests, moving into alpine parklands and dwarf shrubs at higher elevations.

Special needs

Franklin's bumble bees need a sufficient supply of nectar and pollen throughout the colony season. They use a variety of flowering plants, including lupine, California poppy, horsemint, and penny-royal. These bees require abandoned rodent borrows or clumps of grass for nesting.

Limiting factors

Franklin's bumble bees are vulnerable to habitat loss and alteration. Fire suppression contributes to loss of meadow habitat. Disease, pesticide applications, potential competition with honey bees for floral resources, and climate change present additional threats.

Data gaps

Monitor historical sites. Obtain population estimates. Evaluate pathology and control of Nosema bombi [Microsporidia] and other potential disease organisms (such as Locustacrus buchneri [Acarina] and Crithidia bombi [Protozoa]). Determine susceptibility of commercially-reared and wild bumble bee species to pathogens.

Conservation actions

Since this species has not been seen since 2006, surveys that target historical sites are needed. If B. franklini is found, protect important bumble bee habitat.

Key reference or plan

The Xerces Society: Conserving Bumble Bees