Study Finds Western Bumblebee Population In Decline

Jul 10, 2020

A western bumblebee.
Credit Stephen Ausmus, USDA ARS

The Western Bumble Bee Working Group published a study that found the probability of finding a western bumblebee decreased by 93% from 1998 to 2018. The study, published in Ecosphere, explained that this may be because of changes in habitat, climate, and pressures from disease, pesticides, and other animals.

Group member Lusha Tronstad with the Wyoming Natural Diversity Database at the University of Wyoming and her team used butterfly nets and traps that look like flowers to catch and measure numbers of bumblebees, but she said you can also look for western bumblebees yourself.

"We have several bumblebees that live in the Laramie valley, and throughout the state we have around 20 different species," said Tronstad. "The way you know it's a western bumblebee versus another bumblebee is that the tip of their abdomen is white."

Trinstad said her team's goal is to provide unbiased measurements about western bumblebees.

"We'll collect this information and that information will be used either to help manage that species or for the U.S. Fish and Wildlife Service to understand what we know about this species," said Tronstad.

The USFWS will use the evidence from this study in their decision to add the western bumblebee to the endangered species list.

Have a question about this story? Please contact the reporter, Ashley Piccone, at apiccone@uwyo.edu.