Conservation is considered a crisis discipline – a race against time. Reversing a declining species’ trajectory requires extensive knowledge about the reasons for decline. This of course demands that we identify what potential reasons should be investigated in the first place! Unfortunately, these stressors are not always so easily identifiable, and can occur in combination with several others. As you probably have guessed, this applies to bumble bees. The numerous threats to bumble bees complicates our view of their individual and related roles, as well as how to fix them.
The list of threats that bumble bees face is long. Climate change, habitat loss or change, pesticide use, and invasive species are factors that are most widely known to facilitate bumble bee declines. However, recent science has identified yet another threat to bumble bees – parasites.
Bumble bees are hosts to many parasites. Most are relatively harmless, but not all. My role within WPC’s Native Pollinator Initiative, partnered with the University of Toronto Scarborough’s (UTSC) Biodiversity of Urban Green Spaces (aka BUGS) lab and Dr. Mathilde Tissier (Laval University & Bishop’s University), was to jumpstart new research into the prevalence of two kinds of parasites in bumble bees across Southern Ontario and queens being brought into WPC’s bumble bee conservation breeding program. These parasites are the members of the fungal genus Vairimorpha (formerly called Nosema), as well as members of the genus Crithidia.