Professor Farrell sent me a link to this report done by the BBC on a insect survey being done in urban and rural areas of the UK:
http://www.bbc.co.uk/news/science-environment-14380658
While the idea that urban gardens are a more reliable source of food than farmland and nature reserves might have merit, it seems to me that they haven’t thought about (or, more probably, haven’t reported on) certain other factors.
I’ve always gotten a great catch, both from netting and from bee bowls, while working in the cultivated gardens at the Arbortetum, particularly the Bradley Rose Garden and the Leventritt Shrub and Vine Garden. There’s no doubt that bees will flock to gardens. But they shouldn’t discount the role of weeds and wildflowers in the fields; I’ve seen little white grass blooms I would not have otherwise considered flowers crawling with honeybees, and I got my largest catch of bees ever from a field of overgrown grass and wildflowers. In that catch, I saw many of the same bees I’d seen in the gardens (some in greater numbers), but I also saw several types of bees that were totally new to me; strangely shaped black bees with fat thoraxes and skinny abdomens, bees with wide, short abdomens with yellow stripes that don’t quite meet in the middle, even one with yellow spots instead of stripes! So, I wonder if they might not find greater numbers in the cities’ gardens but greater diversity in the fields.
Bee-Search 
Interesting — I wouldn’t have thought that urban areas would provide nearly as many pollinators as rural areas. Like you said, wildlife ecosystems offer so much more diversity, and all organisms really thrive on that (if i recall, something like half of all known species of everything live in tropical rainforests, where they have millions of niches to occupy). It seems strange to me that the ecosystem with the greater diversity wouldn’t also have the greater population. Why do you suppose that is? Is it, maybe, that homogenized urban bee populations are less competitive and so propagate more freely? Or some environmental factor (perhaps specific to the UK?) that impedes the rural populations, like a predator or a shortage of nutrients? I’m curious.
Really cool blog by the way 🙂