Land use and occurrence of Andrena hattorfiana and other threatened wild bees (Hymenoptera, Apoidea) at Stenbrohult, Linnaeus' birth place.
Publikation/Tidskrift/Serie: Entomologisk tidskrift
Dokumenttyp: Artikel i tidskrift
Förlag: Sveriges Entomologiska Förening
During the last decades a striking decline has been observed for wild bees throughout central and north-western Europe, including Sweden. in an area of 64 km' in the parish of Stenbrohult, southern Smaland Andrena hattorfiana, Andrena humilis, Nomada armata and Panurgus hanksianus were studied (in Sweden red-listed as VU, EN, EN and VU). We present occurrence patterns in relation to habitat types for these bee species. They are to a large extent dependent on the herbs Knautia arvensis (occurred in 80% of the 1 x 1 km squares in the study area in 1970-74), Leontodon hispidus (52% of the squares) and Hypochoeris radicata (48% of the squares) for pollen. Andrena hattorfiana was recorded from 72 habitat patches (453 individuals recorded from 38 (59%) squares of 1 x 1 km) and its cuckoo bee Nomada armata from five sites (9 individuals in five (8%) squares of I x 1 km). Unmanaged grasslands supported the largest numbers of Andrena hattorfiana in the study area, but traditionally hay meadows with late harvest supported the highest density and the largest local populations. Panurgus banksianus was recorded from two localities (>30 individuals in 2 (3%) squares of I x I km). Andrena humilis was only found on meadows with late harvest (>51 individuals in 3 (5%) squares of I x l km), frequently visiting flowers of Leontodon hispidus. This is currently the only known larger population in Sweden. The patches with the largest numbers of bees, regarding both species richness and number of individuals of these four species, were meadows managed with late summer mowing. On flower rich meadows in Rashult (in the central part of the study area) all four bee species occurred together. No threatened bees were found at heavily grazed localities.
- ISSN: 0013-886X