The 2025 Great Basin Bumble Bee Bioblitz

This article was originally published in The Midden – Great Basin National Park: Vol. 25, No. 2, Winter 2025.

Bombus centralis, the Great Basin Bumble Bee.

NPS/G. Baker

By Amy Dolan, Xerces Society

To celebrate Pollinator Week 2025, nearly fifty nature enthusiasts from across the Great Basin and beyond journeyed to Great Basin National Park for the Park’s annual Bioblitz event. This year’s bumble bee-focused Bioblitz had volunteers excited to learn more about these fuzzy pollinators—their diversity, life cycle, conservation status, and how to identify them.

The three-day event was facilitated by myself, a conservation biologist with the Xerces Society for Invertebrate Conservation. I coordinate the Mountain States Bumble Bee Atlas, which includes Nevada, Utah, Wyoming, and Colorado. The Bumble Bee Atlas is a community science project where anyone can be trained to conduct surveys to help find and map native bumble bees. The goal is to learn where they are, the habitats they’re using, and the flowers they’re relying on so land managers can make informed conservation decisions. The Xerces Society currently leads Bumble Bee Atlas projects in 20 states across the country.

Participants learn about bumble bees, the Bumble Bee Atlas, and the Xerces Society for Invertebrate Conservation.

NPS/G. Baker

For this year’s Great Basin Bioblitzers, day one was spent in a classroom setting hearing about the 19 different bumble bee species known from Nevada and the unique annual life cycle of a bumble bee colony. Participants learned how bumble bees and other native pollinators have experienced population and range declines due to a variety of threats including habitat loss, pesticides, pathogens, and climate change. They discovered how community science efforts like the Bumble Bee Atlas can help scientists and land managers find and conserve these important pollinators. An optional evening session helped enthusiastic volunteers learn what to look for in order to identify a bumble bee to species.

Bioblitz volunteers conducting Bumble Bee Atlas surveys across the Park.

Jessie Mendoza

Volunteers took to the field on day two, spreading out across the Park to conduct standardized Bumble Bee Atlas surveys. Each survey lasted 45 minutes and took place within a one-hectare survey plot. Bumble bees were caught with insect nets and placed into vials, then photographed and released. Volunteers used coolers of ice to safely anesthetize the bees so they could handle each individual and get up-close photographs of key characteristics used for species identification. Each survey included a brief habitat assessment which documented location, habitat type, floral and nesting resources available, weather conditions, management practices, and any observed land disturbances.

Bumble Bee BioBlitz volunteers examine a bumble bee.

Rachel Stringham

Despite excessive winds causing less-than-ideal survey conditions, volunteers documented 20 bumble bees of six different species in the Park during the Bioblitz. By far, the most common species observed was the aptly named Great Basin bumble bee, Bombus centralis. This quest for bumble bees led both volunteers and researchers to think more intentionally about when and where to look for these pollinators in the future.

After a celebratory breakfast hosted by the Great Basin National Park Foundation on day three, participants headed home with a new appreciation for these amazing pollinators and the skills to become a Bumble Bee Atlas participant in their own communities. To learn more about the Bumble Bee Atlas and how to participate, please visit BumbleBeeAtlas.org.

Bumble Bee species seen at the 2025 Great Basin Bioblitz.