Abstract Habitat loss and fragmentation resulting from increasing urban expansion and densification are the largest drivers of biodiversity loss as they reduce resource availability and increase the distance between remaining patches. This can have devastating ecological and evolutionary consequences especially for species unable to emigrate from poor quality or isolated habitat due to limited dispersal means or strict ecological requirements. Isolation can also contribute to reduced genetic diversity and increased inbreeding affecting species' ability to respond to sudden environmental changes. However, with their heterogeneous green spaces, cities may nonetheless support diverse biological communities. Bees are integral pollinators commonly found in and supported by urban green spaces; however, their eco‐evolutionary response to urbanisation varies interspecifically. While several studies have explored the population and landscape genetics of bees in response to urbanisation, few have examined solitary or specialist species, which may be more susceptible to urbanisation. This study uses genotyping by sequencing to investigate how urbanisation affects the population structure, genetic diversity and gene flow of the solitary, specialist bee species Melissodes druriellus in Canada's most populous city, Toronto . Metrics of genetic diversity were consistent across the sampling region and in many instances were generally low, indicating minimal restriction to gene flow and strong genetic connectivity in what appears to be a relatively panmictic population. Given the persistence of this species, this work suggests that not all specialists are negatively impacted by cities. Future planning decisions should strive to maintain current patch connectivity and continue enhancing existing habitat with suitable host plants.
Ayers et al. (Fri,) studied this question.