Open Collections

MacNaughton, Duncan James

University of British Columbia

Habitat loss is driving global losses in biodiversity. The antelope-brush / needle-and-thread grass (Purshia tridentata / Hesperostipa comata) shrubsteppe, located in British Columbia’s Okanagan Valley, is one of the most biodiverse ecosystems in Canada. However, it is also one of the most at-risk ecosystems in the country, with the majority of its historic range being lost since 1800. One of the primary drivers of this change is agricultural expansion, as conversion of natural habitat to intensive agriculture (ground crops, orchards, and vineyards) has accounted for 79% of the total losses. The Okanagan Valley is one of the most productive agricultural areas in Canada, and relies on crop production and agri-tourism to drive its economy. Many crops in the Okanagan, such as apples and cherries, rely strongly on animal pollination, and while many farms import European honeybees (Apis mellifera) to manage crop pollination, native insect pollinators may significantly increase the pollination services provided to crops. Rapid agricultural intensification, habitat loss, and habitat degradation, however, are putting these native pollinator species at risk of extinction. I conducted a study evaluating the impact of shrubsteppe habitat loss on pollinator community richness, diversity, and composition in BC’s Okanagan Valley by surveying insect communities in shrubsteppe sites that varied in the amount of surrounding natural habitat. I found that the proportion of natural landscape in the surrounding area had a significant positive effect on the richness and diversity of insect pollinator species collected by netting, but not on insects collected via trapping. Similarly, the proportion of natural landscape significantly affected the pollinator community composition of collected by netting and blue-vane traps, but not by pan-traps. These findings provide evidence that increasing the proportion of natural landscapes within agricultural systems supports higher insect pollinator species richness and diversity.

Text

2025-01-13

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/90118

Zoology

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/