Examining Honeybee (Apis mellifera) Dominance Patterns Within Urban Bee Communities Worldwide

Abstract

Urban ecosystems can host diverse bee communities. However, the increasing prevalence of urban honeybees (Apis mellifera Linnaeus 1758) raises concerns about their ecological impact. Using a systematic review of published studies, we obtained 68 datasets representing 46 cities in 15 countries and five continents to test the extent to which honeybees are dominant in urban bee communities worldwide. Honeybees ranked as the most abundant species in ca. 70% of the datasets and accounted for more than 10% of all individuals in ca. two-thirds of the datasets. Moreover, honeybees ranked among the top three abundant species in 70% of studies. Honeybee abundance patterns were consistent across regions and sampling designs, independent of whether honeybees were native or not. At the same time, the degree of dominance varied across cities. These findings highlight the need to address the ecological implications of honeybee dominance, including assessing the effects on wild bee communities and populations and defining strategies to enhance, preserve wild bees, and enhance coexistence with honeybees.

Keywords: Anthophila; Western European honeybee; bees; diversity distribution; urban beekeeping; urban ecosystems.

FIGURE 1

Summary of the literature review and included articles (studies), urban areas and datasets.

FIGURE 2

Honeybees often represent a large part of sampled urban bee faunas across cities and sampling methods. (a) Proportion of honeybees and wild bees sampled in urban areas worldwide (each bar represents a dataset, that is, an urban area linked to a study. In total, there are 68 datasets distributed among 47 urban areas). Datasets are classified according to (1) the sampling method applied for sampling bees (i.e., active = hand‐netting, observations, passive = pan‐traps, interception traps, both = active and passive methods applied together), and (2) the origin status of honeybees in the given urban areas, that is, whether honeybees are outside (non‐native) or inside (native) their natural distribution ranges. (b) Cities represented in the 68 datasets included. (c) Proportion of honeybees according to the sampling type. Letters indicate the results after performing a Tukey test for multiple comparisons to test for differences in the proportion of honeybees and the sampling type.

FIGURE 3

Honeybees are one of the most dominant bee species in bee faunas in cities from North America (a), South America (b), Europe and Asia (c), and Oceania (d). For each region, the rank‐abundance distribution (RAD, left plot) of sampled urban bee fauna and a histogram (right plot) of the honeybee rank in each RAD are provided. The x‐axis divisions represent different bee species and the y‐axis the number of individuals sampled. Each RAD represents a dataset, that is, an urban area linked to a study (in total, 41 datasets distributed in 33 urban areas). Hence, for some urban areas (e.g., Zurich, Switzerland) there are multiple RADs plotted representing different studies conducted in the same city. Circles represent wild bee species and larger squares represent honeybees. Note that the abundances in the RADs have been log‐transformed.