Long-term monitoring of bees in specific sites provides information on changes in species diversity and abundance, especially in areas close to human habitation. Evaluations of this monitoring data combined with relevant measures of anthropogenic activity can aide in interpreting emerging patterns of bee pollinators. In 1972, we sampled bees visiting flowers of a population of the leguminous tree, Andira inermis (W. Wright) DC in a dry forest site adjacent to the town of Liberia, Guanacaste Province, Costa Rica. Slightly more than 800 bees were recorded on the average per tree site, with an overall bee diversity among the trees of approximately 70 species. Standardized bee samples were taken again from the same population of A. inermis in 1996, 1999, and 2004. In each of these years average abundance level per tree was greatly reduced, as was overall species diversity. Andira inermis trees were also observed to have variable attraction for large anthophorid bees versus honey bees. Some trees attracted significantly more anthophorids than honey bees, whereas other trees attracted the opposite.

Since 1972 there were many changes in land use that were directly related to a rapidly growing human population in Liberia. These changes, which greatly modified the natural landscape and vegetation, are believed to have caused a major decline in species diversity and abundance of bees to a low but consistent level. Concurrently, increased urban growth has resulted in many more residential neighborhoods that have a wide variety of ornamental flowering plant species, many of which are native to Costa Rica, that attract a wide variety of native bee species. Evidence is offered to suggest that urban residential areas represent a source of bees that continue to visit A. inermis at low levels in and immediately around Liberia.

Anthidium manicatum (L.) is an adventive species of European origin first recorded in North America in the late 1960's; from that point until 2001 its range on the continent was restricted to the northeast-central USA and central Canada (Ontario, more recently Québec). In 2005, this species was reported from Nova Scotia, a rapid and wide increase in its distribution. In this paper, we document a similar rapid spread of A. manicatum into western North America, including British Columbia and Idaho, and discuss the potential risks of this species in eastern Canada. In addition, the potential of DNA barcoding as a rapid and reliable means of recognizing adventive bee species is advocated.

In bees, both body size and shape may show considerable variation associated with differences between females and males, among populations, and due to local environmental variation. We studied multiple parameters of body size and shape of the large carpenter bee Xylocopa virginica, to understand how body size and shape are influenced by sex, and by seasonal and annual variation. In addition, we compared bees from a population near the northern edge of the range (southern Ontario, ON) which experience relatively severe winters, to bees from the central portion of the range (Maryland, MD), which experience milder winters. Overall, males and females differed in linear dimensions but were more or less the same mass. Seasonal variability was investigated using ON bees. In winter, females and males had the same overall mass, but male thoracic volume and linear dimensions such as head capsule width, intertegular width, and costal vein length, were all larger for a given mass. In summer, males weighed less than females, due to loss of mass from the abdomen. Year-to-year differences in size and shape were indicated in MD bees, which exhibited significant differences in linear dimensions and dry mass, but not wet mass. In addition, northern bees were smaller than southern bees in terms of linear dimensions, but it is not entirely clear if overwintering mass differs. We suggest that seasonal and sex differences in size are related to the different flight activity patterns of males and females in summer, and that geographic differences between the two populations are related to the length and duration of winters.

The western US bee Osmia aglaia Sandhouse is resurrected from synonymy with O. laeta Sandhouse. Confusion resulted from errors in paratype identification, which are herein corrected. New distinguishing morphological characters are provided that justify the specific status of O. aglaia.

Alley cropping is an integrated land management practice growing economic crops between rows of trees. This paper examines the effects of alley cropping on carabid beetles and other ground dwelling arthropod predators on species diversity and abundance by testing for differences among ground vegetation treatments in alleyways. Arthropods were collected with pitfall traps in two alley-cropped areas using the ground cover treatments of alfalfa, smooth bromegrass, and a vegetation-free control. Although not generally statistically significant, brome had the lowest means of any of the ground vegetation treatments, possibly due to the relative impenetrability of the thick grass. We found few significant differences among treatments. Carabidae numbers were negatively correlated with relative humidity and positively correlated to soil temperature and moisture. Sampling methods other than pitfall trapping are needed in future studies to clarify the role of ground cover in arthropod predator diversity and abundance in an alley cropping practice.

The potential for rootworm larvae to move between grassy weeds and transgenic maize may be important in resistance management of transgenic rootworm-resistant maize. An experiment was conducted under growth chamber and greenhouse conditions to determine the impact of initial feeding of rootworm larvae on alternate hosts, followed by switching host to transgenic maize, on the development of western corn rootworm (Diabrotica virgifera virgifera LeConte). Two grassy weed species, rootworm-resistant Cry3Bb1 transgenic maize (MON863, YieldGard® Rootworm) and its isoline, were infested with 50 neonate larvae per container four weeks after planting. Large crabgrass (Digitaria sanguinalis (L.) Scop), and giant foxtail, Setaria faberi R. A. W. Herrm both in the Poaceae, were chosen because they were relatively good hosts in previous studies. On the 5^th, 10^th, and 15^th d after infestation, the Tullgren funnel technique was used to facilitate larval movement (host-switching) from the original host plants to the final hosts (MON863 or its isoline). Beetle emergence and fecundity were significantly impacted by the original host, the final host, and their interaction. The original and the final host plant also significantly impacted the sex ratio of the beetles. The host-switching date did not impact any of those three variables. Only the original host had a significant impact on egg viability. Significantly more reproductively fit beetles were produced from larvae that fed on an alternate host before moving to transgenic maize than from larvae fed exclusively on transgenic maize. Interactions with alternate hosts may influence transgenic maize resistance management models.

Three morphologically similar Bahamian scoliid wasps are traditionally described as two species, Campsomeris bahamensis and C. trifasciata, the latter of which is divided into two subspecies: C. t. trifasciata and C. t. nassauensis. We examined these taxonomic groups by comparing the genetic diversity of different Campsomeris populations collected at various locations on several islands. DNA was extracted from individual male and female specimens and preferentially amplified by the polymerase chain reaction, using a unique random primer for each analysis. The DNA products were compared by electrophoresis. Results indicate overlapping genetic profiles between these three taxonomic groups. The genetic variation between these three taxa is similar to the variation found within one taxon collected from different islands.

An inventory of the dragonflies and damselflies (Insecta: Odonata) at the Lostwood National Wildlife Refuge (LNWR) was conducted during the summer of 2003. Adult censuses and larval sampling at 32 wetland sites produced 10 dragonfly and 14 damselfly species that were resident in the refuge. In 2006, two additional species were added. The odonate fauna of LWNR consisted primarily of widespread, common species that are adapted to fishless lentic communities and tolerant of alkaline and impermanent water regimes. Enallagma annexum (Hagen), Enallagma boreale Selys, Lestes disjunctus Selys, Lestes congener Hagen, Sympetrum costiferum (Hagen), and Sympetrum internum Montgomery were the most abundant odonates at the refuge. The odonate communities of semipermanent, oligosaline ponds were the most diverse and included species of Aeshna, Anax, Libellula, Leucorrhinia, Sympetrum, Lestes, Coenagrion, Enallagma, Ischnura, and Nehalennia. Large polysaline lakes were inhabited only by Ischnura damula Calvert and four species of Enallagma. Seasonal ponds that remained flooded until mid-July produced large numbers of Sympetrum internum, Lestes disjunctus, and Lestes unguiculatus. Spring-fed bogs and fens supported several species that were rare at the refuge including Sympetrum danae (Sulzer), Sympetrum semicinctum Say, and Amphiagrion abbreviatum (Selys). Long-term monitoring of odonate diversity and abundance may be useful in tracking the effects of climate change in the prairie pothole region but must take into account yearly fluctuations due to variation in winter and summer precipitation.