Floral Resources and Nesting Requirements of the Ground-Nesting Social Bee,Lasioglossum malachurum(Hymenoptera: Halictidae), in a Mediterranean Semiagricultural Landscape

Abstract

In order to adopt correct conservation strike plans to maintain bee pollination activity it is necessary to know the species' resource utilisation and requirements. We investigated the floral resources and the nesting requirements of the eusocial beeLasioglossum malachurumKirby at various sites in a Mediterranean landscape. Analysis of bees' pollen loads showed that Compositae was the more exploited family, although interpopulations differences appeared in the pollen types used. From 5 to 7 pollen types were used by bees, but only as few as 1–1.9 per load. Variations of the pollen spectrum through the annual nesting cycle were conspicuous. At all sites, bees nested in horizontal ground areas with high soil hardness, low acidity, and rare superficial stones. On the other side, the exploited soil was variable in soil granulometry (although always high in % of silt or sand) and it was moderately variable in content of organic matter and highly variable in vegetation cover. Creation of ground patches with these characteristics in proximity of both cultivated and natural flowering fields may successfully promote colonization of new areas by this bee.

Small sweat bees (Hymenoptera: Halictidae) as potential major pollinators of melon (Cucumis melo) in the Mediterranean

“…compact soil almost avoid of vegetation; Polidori et al . ). Severns () successfully attracted Lasioglossum females to nests in artificially created plots of bare ground while planting seeds of a lupine species at a site in Oregon, with more than 300 nests established in 3 years.…”

“…Instead, we suggest that it could be useful to attract nestfounding Lasioglossum females around the crop by providing soil patches with characteristics adequate for nesting (e.g. compact soil almost avoid of vegetation; Polidori et al 2010). Severns (2004) successfully attracted Lasioglossum females to nests in artificially created plots of bare ground while planting seeds of a lupine species at a site in Oregon, with more than 300 nests established in 3 years.…”

The Role of Annual Flowering Plant Strips on a Melon Crop in Central Spain. Influence on Pollinators and Crop

“…By contrast, according to Hicks et al [77], C. officinalis, the most visited plant in 2014, produces a lot of both pollen and nectar compared to the other 65 plant species, thus preventing the displacement of bees to the melon crop. In Mediterranean landscapes, it is known that Compositae was the most exploited family for the species L. malachurum [78]. Besides, melon has a low number of open flowers each day, the flowers are relatively hidden and unattractive to pollinators compared to wildflowers, and only offer a small amount of nectar and pollen [50].…”

Do wild bees complement honeybee pollination of confection sunflowers in Israel?

“…(269 individuals) were Lasioglossum spp. (polylectic but with known preference for Asteraceae, Polidori et al 2010), and four spp. are known as Asteraceae specialists (Osmia signata, Osmia dives, Megachile albisecta and Colletes similis; 20 individuals in total).…”