Livestock Grazing Shapes the Vegetation Structure and Subsequent Habitat Use by the Endangered Skipper Pyrgus ruralis lagunae (Lepidoptera: Hesperiidae).

Many species adapted to alpine and montane meadow ecosystems are at risk of extinction. The skipper Pyrgus ruralis lagunae Scott is a mountaintop butterfly restricted to San Diego County, CA, a federally listed endangered species, and is in imminent risk of extinction. Historically, P. r. lagunae was found in the Laguna and Palomar mountains. We did not detect the skipper in the Laguna Mountains, and the species has likely been extirpated from this area, which represents half of its historical range and is the type locality. We studied three populations on Palomar Mountain. Skippers primarily occupied areas close to creeks or in adjacent ravines at two nongrazed sites. The third site is grazed by cattle, and skippers were found close to the forest edge. At nongrazed locations, creek areas had higher cover of intermediate-height vegetation, more bare ground, and more flowers compared with unoccupied areas of the same meadow. The vegetation at occupied and unoccupied areas within the grazed meadow were similar. Even so, skippers occupied areas with more bare ground as well as greater species richness of flowering plants. A grazing exclosure was previously installed in an attempt to protect and enhance skipper habitat, but skippers did not use the dense grasslands that developed inside the exclosures. Contrary to the prevailing theory, protection from grazing did not improve skipper habitat. This illustrates how management based on inadequate biological information can hinder well-intentioned conservation efforts.

THE MELOIDAE (COLEOPTERA) OF WISCONSIN.

There are recent faunistic surveys of selected insect taxa (e.g. Mutillidae, Scarabaeoidea, and Tenebrionidae) in Wisconsin but a formal investigation of the Meloidae (blister beetles) is lacking. The blister beetle fauna of several states has been published, but this study represents the first in the Midwestern United States. We provide a comprehensive list of all meloid species documented from Wisconsin. Also included are taxonomic keys as well as summaries for each species (species pages) which includes taxonomy, description, and natural history. Specimens were obtained from public and private collections, and field sampling. This survey advances our knowledge of meloids in Wisconsin as well as provides a contribution beyond this geographic area. During this survey, 28 meloid species in seven genera were documented in Wisconsin from 2605 specimens. Of these taxa, 10 species are considered new state records. While Epicauta pensylvanica represented nearly half of the specimens reviewed, and likely inhabits all counties within the state, other species were rarely encountered. This includes 10 species which were represented by seven specimens or fewer in this study. It is unclear if the rarity of these specimens is correlated with the rarity of the species or if it is due to other factors. Regardless, these rarely collected meloids in Wisconsin warrant further attention.

Genetic population structure of the blister beetle, Gnathium minimum: core and peripheral populations.

Populations on the periphery of a species' range tend to contain lower genetic variation and increased genetic differentiation compared to populations at the core of a species range, although some exceptions to this generalization occur. The blister beetle Gnathium minimum (Say) exhibits a wide-ranging distribution in the western United States but has peripheral or disjunct populations in Mexico, Florida, and Wisconsin. We used amplified fragment length polymorphism (AFLP) to compare the genetic variation and magnitude of genetic differentiation of the Wisconsin peripheral population to western core populations (Colorado, Kansas, New Mexico, and Texas). The proportion of polymorphic loci was 53.6 and 54.3, and expected heterozygosity 0.1864 and 0.1933 for the Kansas/Colorado (n = 87) and New Mexico/Texas (n = 35) regions, respectively. Specimens from Wisconsin (n = 121) had a lower proportion of polymorphic loci (38.4) and expected heterozygosity (0.1475). Genetic cluster estimation with GENELAND and F ST values showed greater genetic differentiation among the sampling locations within Wisconsin compared to core regions. Significant isolation-by-distance (IBD) was also observed in Wisconsin but not within the core regions. Lower genetic variation and increased isolation may reduce the Wisconsin population's ability to respond to change, thereby increasing their susceptibility to extinction.