Note to readers, attached is the complete final report for FNE96-138
Blueberries and cranberries require bees for pollination. In Maine it has generally been the practice to lease hives when these crops are in bloom, but this has become quite expensive in recent years, and threatens to become more so as beekeepers grapple with serious infestations of bee mites. Mr. Kelley thought as an alternative to encourage the populations of native bees. He surmised that these are not more numerous for want of nesting sites so, with the help of a high school woodworking class, he set about to create some. They built 101 blocks for leafcutter bee nests and 32 houses for bumble bees, and set these around Mr. Kelley’s 50-acre blueberry field, as well as the three-acre cranberry bog of his neighbor. The leafcutter bee blocks were nailed either to 3-foot long stakes, or to trees, about five feet off the ground. Some of the bumble bee houses were set on the ground, and others were buried. They also set out 36 bales of hay, intended either as bumble bee nesting sites or as hibernation sites for over-wintering queens.
Neither the bee houses nor the bales of hay succeeded in attracting bumble bees, but the leafcutter bee blocks were successful. Leafcutter bees came to occupy about a quarter of the blocks, despite some competition from ants, spiders, and other insects. Mr. Kelley is continuing and elaborating this project for a second year, under another SARE grant. He believes the leafcutter bees will eventually occupy the remaining blocks, as the next generation of queens spawned in the already occupied blocks looks for new nesting sites. He is still hopeful of attracting bumble bees too; bumble bees sometimes move into abandoned mouse nests, and the bumble bee houses did succeed in attracting some mice this year.