Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/20/2002
Publication Date: 4/3/2003
Citation: CANE, J.H. ANNUAL DISPLACEMENT OF SOIL IN NEST TUMULI OF ALKALI BEES (NOMIA MELANDERI) (HYMENOPTERA: APIFORMES) ACROSS A LANDSCAPE. JOURNAL OF KANSAS ENTOMOLOGICAL SOCIETY. 2003. 76(2):p.172-176 Interpretive Summary: Alfalfa seed growers who depend upon the alkali bee for pollination services must maintain the soil nesting beds of this bee for decades. Soil that the bees annually excavate and bring to the surface is often swept away by wind. Can this erosion lead to significant surface subsidence? Across the Touchet Valley of se WA, 9 million alkali bees annually excavated 96 tons of soil, but this amounts to only 4 cm of surface subsidence on nesting beds in half a century. Bee-induced ereosion is thus minimal.
Technical Abstract: Thousands of bee species nest in the ground, sometimes gregariously, digging tunnels whose excavated soil is pushed to the surface as tumuli. To quantify tumulus production across a landscape, nesting female alkali bees (Nomia melanderi) were censused for the 155 km2 Touchet Valley of seWA, where its nest sites are managed to pollinate alfalfa seed fields. Nine million nesting females collectively brought 96 tons of soil to the surface in their tumuli, much of which is subsequently eroded away by wind or rain. Even at this rate, however, the oldest populated nest site would have cumulatively lost only four cm to surface subsidence as a result of the past half century¿s nesting activity.