Abstract
A5: Packer, L. and G. Knerer. 1986. An analysis of variation in the nest architecture of Halictus ligatus in Ontario. Insectes Sociaux. 33:190-204.
Abstract: Nest architecture of Halictus ligatus was studied at Victoria, southern Ontario; over 130 nests were excavated in 1984. The most important findings are as follows. Nest failure was lower in vegetated areas than in bare ground. Nests with entrances hidden under leaves may suffer less mortality from parasites than those out in the open. Loops around cells are dug in response to moist soil conditions and appear to be an intermediate step towards cavity formation. Brood mortality due to mould seemed to result from cell waterlogging which the excavation of loops may help to prevent. Cells near the surface may suffer from waterlogging after heavy rains. Nests situated in denser vegetation suffered less mortality from mould. Gyne-producing cells are larger than male or worker-producing ones. Mandibular wear is an accurate measure of the amount of excavation performed by an individual female.