2007 Annual Report 1a.Objectives (from AD-416) Overall, our objectives are to identify specific environmental and management-related factors associated with the specific forms of mortality that vary seasonally and with cell position within nests. Expansion of the research to include pollen types used by females will not only improve our understanding of the causes of mortality (if pollen type and nutritional value is involved), but allow us to examine factors that influence the pollination efficiency of adult bees. With regards to the latter, relatively inexpensive forms of vegetation management (including weed control) may prove to have an important effect on pollination and bee mortality. However, it is not clear at this time whether elimination of alternative pollen sources will have a net positive or negative effect on the economics of seed production. For example, it is quite possible that the nutritional benefits of a diversified pollen diet outweigh the costs associated with bees directing part of their foraging activities to non-alfalfa plants. 1b.Approach (from AD-416) While continuing to examine the types of pollen carried , we will also examine: 1)Actual numbers of pollen grains carried by individual females. 2)Distribution of alfalfa pollen on bodies of bees. 3)Seasonal trends in pollen types used.4)Distances from shelters at which bees forage for pollen. 5)Effect of flower densities and available pollen types on movement patterns of the bees; and. 6)Sexual differences in pollen types carried. To date, we have collected only females, but in 2004 we will collect both sexes; this will help determine the potential role of male bees in pollination. 3.Progress Report This report serves to document research conducted under a specific cooperative agreement between ARS and Montana State University. Additional details of the research can be found in the report for the parent project 5428-21000-010-00D Pollinating-Insect Biology, Management, and Systematics Research. During the summer of 2006, we examined the effect of insecticides on bee mortality, testing the activities of a range of chemistries in two applications (early June and mid-July) on lygus bugs and pea aphids, including their residual effects on beneficial predatory insects and bees, both native and non-native. The study was set up at two sites (Yellowstone and Carbon Counties) in eastern Montana. Megachile rotundata were released in late June at both sites, where they nested in "mini-shelters" placed individually within each chemical treatment plot. Thus, leafcutters were present in the field at the time of the second spray application. These nesting materials were collected in late August and placed in cold storage for overwintering in mid-October. Cell dissections will be undertaken starting this January to examine and compare mortality of bee larvae within each chemical treatment. We are in the process of sorting and analyzing sweep samples that were collected every 3-7 days at both sites from June through August. Sweep sample sorting and preliminary analyses have been completed for the Yellowstone County site. Results indicate that several chemical treatments (including novaluron and neemix) significantly reduced lygus numbers while maintaining favorable numbers of beneficial insect predators, with no discernible impact on adult pollinators detected based on our research so far. Other pesticides (bifenthrin) exhibit a greater negative impact on natural enemies numbers. We also collected plant samples for assessment of the effects of insecticide treatments on seed yield. For both Apis mellifera and other bees collected in sweeps, there were no statistical differences between chemical treatments. A. mellifera was first detected in sweep samples on 5 June, at or below one honey bee per plot through 19 June. However, after the release of M. rotundata, honey bees entirely disappeared from sweep samples until the last few samples of the season (28 July and 7 August). Bees of other taxa were uncommon in sweep samples across the season. Peak numbers were collected on 20 July (N=6), all of which were an (as yet) unidentified species. On 13 July, day four following the second spray application, 3 m transects were established between rows in the center of each plot at both research sites. Foliage was pulled aside and the strip of exposed soil between alfalfa rows was examined for the presence of M. rotundata killed by chemical exposure. No bees were found in any of the treatments. While this may indicate zero bee-kill, activities of scavengers such as ants and / or grasshoppers is a plausible explanation for our observations. ADODR monitoring activities included e-mails and conference calls.