Captive rearing success and critical thermal maxima of Bombus griseocollis (Hymenoptera: Apidae): A candidate for commercialization?

Authors: CHRISTMAN, MORGAN - Utah State University; SPEARS, LORI - Utah State University; Koch, Jonathan; Lindsay, Tien; STRANGE, JAMES - The Ohio State University; BARNES, CODY - Utah State University; RAMIREZ, RICARDO - Utah State University

Submitted to: Journal of Insect Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/16/2022
Publication Date: 11/18/2022
Citation: Christman, M.E., Spears, L.R., Koch, J., Lindsay, T.T., Strange, J.P., Barnes, C.L., Ramirez, R.A. 2022. Captive rearing success and critical thermal maxima of Bombus griseocollis (Hymenoptera: Apidae): A candidate for commercialization? Journal of Insect Science. 22(6). Article 2. https://doi.org/10.1093/jisesa/ieac064.
DOI: https://doi.org/10.1093/jisesa/ieac064

Interpretive Summary: Domesticated bumble bees (Bombus) are the primary pollinators of several crops within greenhouse settings. In this study, we evaluated the commercialization potential of B. griseocollis, a broadly distributed species throughout the U.S., by assessing nest initiation and establishment rates of colonies produced from wild-caught queens, creating a timeline of colony development, and identifying lab-reared worker’s critical thermal maxima (CTMax) and maximum lethal temperature. From 2019 to 2021, 70.6% of the wild-caught B. griseocollis queens produced brood in a laboratory setting. Of these successfully initiated nests, 74.8% successfully established a nest (produced offspring), identifying high rearing success rates of B. griseocollis in a laboratory setting. Additionally, B. griseocollis workers had an average CTMax of 43.5ºC and experienced death on average at 46.4ºC, suggesting B. griseocollis can withstand high temperatures which may be advantageous due to ongoing and project climate change. Overall, these findings determined that B. griseocollis should continue to be evaluated for commercialization purposes throughout the U.S.

Technical Abstract: Domesticated bumble bees (Bombus) are the primary pollinators of several crops within greenhouse settings. However, B. impatiens is the only species currently available for purchase in North America. As an eastern species, concerns have been expressed over their transportation outside of their native range. Therefore, there is a need to identify regionally appropriate candidates for commercial crop pollination services, especially in the western U.S. In this study, we evaluated the commercialization potential of B. griseocollis, a broadly distributed species throughout the U.S., by assessing nest initiation and establishment rates of colonies produced from wild-caught queens, creating a timeline of colony development, and identifying lab-reared worker’s critical thermal maxima (CTMax) and maximum lethal temperature. From 2019 to 2021, 70.6% of the wild-caught B. griseocollis queens produced brood in a laboratory setting. Of these successfully initiated nests, 74.8% successfully established a nest (produced offspring), identifying high rearing success rates of B. griseocollis in a laboratory setting. Additionally, B. griseocollis workers had an average CTMax of 43.5ºC and experienced death on average at 46.4ºC, suggesting B. griseocollis can withstand high temperatures which may be advantageous due to ongoing and project climate change. Overall, these findings determined that B. griseocollis should continue to be evaluated for commercialization purposes throughout the U.S.