Many of the recent investigations into bees has focused on honeybees and bumblebees, with relatively little research on the problems facing solitary or communal bees.  A  female solitary bee must find a nest, collect pollen, then lay eggs and provide food for her offspring.  In contrast, communal bees share a common entrance to a nest where there are a number of females, but each female maintains her own area and offspring. There is no hierarchy within the communal nest, for example, no queen. It is known that the diet of bees has changed over the years.   In the past, the bees were able to forage and collect pollen and nectar from a wide variety of native plants.  However, the loss of ‘natural wild’ areas means that their diet is often dominated by a small number of plants, such brambles, clover and dandelions. Studies have indicated that some pollens have low levels or lack certain amino acids.  Bees need the same essential amino acids as us.  Without a supply of these particular amino acids  the development and growth of bees is impaired,  disease resistance is reduced the ability to raise the brood is compromised.   So, it is important to find ways to offer our pollinators a range of plants / pollen to provide all their essential nutrients.  An abundance but limited range of flowers (and hence pollen / nectar) will not necessarily meet the needs of the pollinators.  The changing floral landscape may be more challenging for the solitary and communal bees.  Much depends on how far they can forage and how flexible they are in terms of their food sources.  A species that can forage over a wide area and that can collect pollen from a number of different flowers might well survive in a nutritionally deficient area.  Solitary bees that only forage over short distances (when compared to honeybees) are likely to be challenged by the nutritional status of nearby flowers, and the changing agricultural / urban environment.  Poor nutrition could lead to rapid population declines in solitary species.  Bees that live in colonies and have a social organisation can share resources and possibly change their foraging efforts.  It is important that measures are found to support the diverssity of native plants both in rural and urban locations if populations of the various pollinators are to be maintained. Further information on solitary bees and the changing climate can be found here.