Decline in Saskatoon Berry Abundance, Southern Manitoba

There has been a drastic decline in abundance of saskatoon berries (Amelanchier alnifolia) on mixed forest land, located 4 kilometers north of Glenboro, Manitoba. For years, the saskatoons provided a plentiful berry harvest; however, since 2020, it seems that berry production has all but halted completely. Harvesting is no longer sustainable, and what little remains of a once bountiful crop is left for the birds and the bears. Discussions with other local landowners in the area indicate similar trends.

The implications of this observation increase with scale; many orchards harvest saskatoon berries for fresh fruit or preservatives and declines in berry abundance would likely lead to economic challenges (McGarry et al., 2005). Although saskatoon berries alone are unlikely to push the world into an economic crisis, overharvesting of renewable resources has the potential to approach ecological limits (Farley & Voinov, 2016). Recognizing that depleted berry crops may have residual effects on local wildlife and increase human-wildlife conflicts (McCarty, 2002) amplifies the significance of this observation.

This property is largely untouched and undeveloped; the only anthropogenic activities that have occurred are berry harvesting and one white-tailed buck annually, and it is unlikely that the landowners are directly responsible for any noticeable changes. Although saskatoons alternate years of sparse and heavy crop (McGarry et al., 2005), the abrupt halt of berry production noted in this observation is not consistent with this pattern.

Climate change, and the prevalence of pests and invasive species (IPBES, 2019), may affect productivity of saskatoons. Changing weather patterns can impact productivity and can increase the overlap between pests and fruiting or flowering trees (Bhattacharjee et al., 2022). Anthony Mintenko, Provincial Fruit Crops Specialist in Manitoba, suggests that droughts in 2021, 2022, and 2023 coupled with the drought-prone sandy-loam soil texture that dominates this area is a likely explanation for the decrease in berry production. Further stressing the saskatoons to the point of low flower development (ergo low fruit production) was extreme and prolonged heat stress experienced in Southern Manitoba during the three growing seasons noted above.

References

Bhattacharjee, P., Warang, O., Das, Su., & Das, Sh. (2022). Impact of climate change on fruit crops: a review. Current World Environment, 17(2), 319-330. http://dx.doi.org/10.12944/CWE.17.2.4

Farley, J., & Voinov, A. (2016). Economics, socio-ecological-resilience, and ecosystem services. Journal of Environmental Management, 183(2), 389-398. https://doi.org/10.1016/j.jenvman.2016.07.065

IPBES. (2019). Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. IPBES secretariat, Bonn, Germany. 56 pages.

McCarty, J.P., Levey, D.J., Greenberg, C.H., & Sargent, S. (2002). Spatial and temporal variation in fruit use by wildlife in a forested landscape. Forest Ecology and Management, 164(1-3), 277-291. https://doi.org/10.1016/S0378-1127(01)00612-0

McGarry, R., Ozga, J.A., & Reinecke, D.M. (2005). The effects of ethephon on saskatoon (Amelanchier alnifolia Nutt.) fruit ripening. Journal of the American Society for Horticulture Science, 130(1), 12-17. https://doi.org/10.7939/r3-jf2v-jw66