Competitive Interactions between Apis and Bombus Essay
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The invasive European honeybees create a competitive environment for the native bumblebee as their ecological niches (species’ total use of abiotic and biotic resources) overlap; thus, creating a niche differentiation (the increase in species using resources causes a wider range of resources being used) between the two species. The invasive and native bees exemplify a symbiotic relationship in which interaction could possibly be detrimental to both species—competition (an interaction in which species use the same resources). Moreover, the invasive European honeybee (Apis mellifera) decreases the population of the native bumblebee (Bombus occidentalis) in northern California by creating a niche overlap and competition for available…show more content… Although it is difficult to directly exemplify the impact of invasive European honeybees on native bumblebees through floral resources, many studies prove there is an indirect relationship between the species concerning overlapping of their ecological niche (Thomson 2004). Diane Thomson conducted an experiment measuring the impacts of the invasive honeybee on the native bumblebee through competition for nectar and pollen resources. Each summer from 1998 through 2000, two to three Apis colonies (each consisting of 10,000-15,000 workers) were introduced into three sites from early June to early September (Thomson 2004). Each Apis colony was placed 2 km apart. For the native bumblebees, B. occidentalis colonies were located at 10 m, 500 m, and 1000 m away from each site. Since there are three distances, and three different sites, there were nine B. occidentalis colonies in total. The B. occidentalis species was placed in the same location every year; however, the distance treatment was altered (Thomson 2004). To reduce the factors that may alter the results, laboratory-reared colonies were used to minimize any differences in the Bombus colonies and weighed to keep the amount consistent (Thomson 2004). Overall, Thomson’s experiment exemplified the direct effects of the invasive Apis species on reproductive success and foraging activity of the native Bombus.
Observations showed Apis foragers declined with distances in flower patches (Thomson 2004). Simply,