An unusual surge in aphid populations in St. Albert, Alberta, led to widespread honeydew residue on artificial surfaces, attributed to climate conditions favoring aphid reproduction.
In July 2024, a clear, sticky residue appeared in residential neighborhoods in St. Albert, Alberta, Canada. The residue was honeydew, a secretion from aphids, and other communities in central Alberta experienced the same phenomenon (Ekelund, 2024; Vaessen, 2024). Large aphid populations caused the high levels of honeydew, likely as a result of climate conditions. Multiple biological functions of aphids are temperature dependant and therefore global warming likely favors aphid populations through processes including reproduction and development (Hullé et al., 2010).
The honeydew did not appear to have significant ecological impacts or affect natural surfaces, like trees, grasses and soils. However, sticky honeydew covered artificial surfaces, such as sidewalks, roads and vehicles, and easily transferred to other surfaces, for example onto the shoes of those who walked along the affected sidewalks. The honeydew likely had minimal economic impact as it was easily washable and did not appear to leave any lasting damage. While cars or other affected items may have required washing, the next rainfall cleaned roads and sidewalks.
The large aphid population had various implications on the local environment. For example, following the honeydew incidents, the area witnessed a greater prevalence of lady beetles and wasps, common aphid predators (Mahr, n.d.).
References:
Ekelund, B. (2024, July 13). “They just go ham”: How a small insect is leaving a big mess in some Edmonton neighbourhoods. CTV News Edmonton. https://edmonton.ctvnews.ca/they-just-go-ham-how-a-small-insect-is-leaving-a-big-mess-in-some-edmonton-neighbourhoods-1.6962970
Hullé, M., Cœur d’Acier, A., Bankhead-Dronnet, S., & Harrington, R. (2010). Aphids in the face of global changes. Les Pucerons : Modèles Biologiques et Ravageurs Des Cultures, 333(6), 497–503. https://doi.org/10.1016/j.crvi.2010.03.005
Mahr, S. (n.d.). Aphids, in-depth. Wisconsin Horticulture. https://hort.extension.wisc.edu/articles/aphids-2/
Vaessen, D. (2024, July 18). Aphid explosion in Alberta creates sticky situation. Global News. https://globalnews.ca/news/10631448/aphids-calgary-sticky/
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