Project Number: 5428-21000-013-04
Project Type: Trust

Start Date: Oct 01, 2007
End Date: Aug 30, 2009

Objective:
Our goal is to evaluate and specify thermal management practices for blue orchard bees (BOB) in California to enable successful handling of BOB populations that differ in climatic adaptations attributable to their geographic origins (i.e., California, Washington and Utah. To understand thermal and seasonal adaptations of BOB populations from the different geographic regions, we will experimentally investigate BOB development with regard to: 1) the impact of average California temperatures and their duration on bee development and mortality, 2) the effects of record summer heat on bee development and mortality, and 3) the impact of pre-wintering duration on survival, emergence rate and emergence success of bees managed for California almond pollination. Comparison of development and survival of bees from the three source populations will afford important information for better management practices for BOBs, especially when they are used outside their native climatic regions.

Approach:
We will compare three geographically distinct populations of BOBs. Two populations will be obtained from the primary regions that currently supply BOBs for California's pollination needs, i.e., northern Utah and Washington. The third population will be one that we currently are acquiring through trap-nesting in the southern Central Valley of California. Development of bees will be monitored under natural temperatures in California. Additionally, a more intensive study of BOB development under various temperature regimes will be performed using environmental chambers in the laboratory in Logan, Utah. Respirometry will be used on laboratory bees to assess metabolic activity in larvae and diapausing adults. Overwintering survival and subsequent spring adult emergence will be evaluated.