Citizen Science – Monitoring Varroa Mites



Beekeepers from across the province participated in a Citizen Science project with BC-TTP. We distributed three online surveys: Spring, 2022; Fall, 2022; and Spring 2023. The aim of the project was to investigate management practices and Varroa destructor levels in different parts of BC. This is what we got:



Spring 2022 

    • 42 participating colonies 

    • 16% of the colonies from the Okanagan 

    • 2% Cariboo 

    • 4.72% Kootenay 

    • 7.14% Omenca Skeena 

    • 4.72% Peace Region 

    • 7.14 South Coast 

    • 11.90 % Thompson Nicola 

    • 45.23% Vancouver Island/Coast 

    • Methods to monitor mites included: alcohol wash, icing sugar method, and sticky papers 

    • 30.95% of the colonies were monitored with alcohol wash 

    • 57.14% of the colonies were monitored with the icing sugar method 

    • 11.90% with sticky papers 

    • Spring treatments included: formic acid, oxalic acid, thymol, and amitraz.  

    • The mean percentage of mites in the spring was 1±0.25 

    • The mean colony strength was 0.83±0.16 (measured as the proportion of frames covered in bees)

Fall 2022 

    • Mean percentage of mites was 2.8±0.69 

    • 58% of the colonies were monitored before treatment, but not after treatment. 

    • Fall treatments mentioned included: formic acid, oxalic acid, amitraz, hops (HopGuard®), and combination of treatments (e.g. formic acid followed by amitraz). 

    • The mean colony strength was 0.73±0.024 (measure as the proportion of frames covered in bees). 

    • 85% of the colonies were monitored in September, and most with alcohol washes (98.83%)


Spring 2023 

We didn’t receive many responses, and we were not able to determine de relationship between mite levels in the fall with colony mortality in the spring. However, from the 93 colonies that we received information we found that: 

    • Colony mortality was higher than the provincial average (32.1% in 2022); 40% of the colonies that were alive in November of 2022 died overwinter. 

    • A Chi2 test of independence showed no differences in the proportion of dead colonies between the seven participating regions (Chi2=11.88, df=6, p=0.065, α of 0.05). The participating regions included Thompson Nicola, Okanagan, South Coast, Kootenay, Vancouver Island/Coast, Cariboo, and Omenca Skeena. 

Positive Outcomes: We were able to connect with beekeepers from different regions, ask people where they are located and when their season starts and what flowers are blooming when.

We would like to thank all the participating beekeepers for taking the time to monitor the colonies and share their data. This information will help us design future projects!