Comparative single-visit pollination efficiencies of bees at alfalfa are planned for July 1999, as is evaluation of potentially detrimental exploitative competition with honey bees for nectar. Richest in protein are those nectarless flowers that bees must buzz to extract pollen. Hence, there seems to be no compensation by adults in either pollen choice or nest cell provisioning. Global change issues and bees Stratospheric ozone depletion and resultant intensification of UV-B at Earth's surface is demonstrated to elicit differing, but largely minor flowering responses in a wild flower and an oil seed crop, with limited implications for the reproductive success of managed blue orchard bees. We are finding that isolated patches lose species within a decade, particularly less common specialists and larger-bodied generalists.
Smaller patches are depauperate in most specialists.
Conversely, even very small parcels or reserves appear to be adequate for retaining populations of the more common bees species, including floral specialists. Availability of suitable nesting substrates appears to be crucial, as cavity-nesting species have in general proliferated in the desert city where this study is being performed It appears that reserves of very modest size can readily retain most of its fauna of pollinating bees for at least 70 years. Golf courses have long been regarded as biological deserts because of their relative vegetative uniformity, and their heavy use of pesticides and fertilizers. After surveying three golf courses in eastern Oregon and Washington for native bee and wasp species, we have begun to enrich areas of the courses with native plant species and with materials that will encourage bees to nest and forage. We have also placed trap-blocks in representative native habitat to obtain populations of native species that may be subsequently imported onto the golf courses, thereby expediting their use as reserves.