Kevina Vulinec

Primate and Dung Beetle Communities in Secondary Growth Rain Forests: Implications for Conservation of Seed Dispersal Systems

Conservation efforts are often aimed at one or a few species. However, habitat sustainability relies on ecological interactions among species, such as seed dispersal. Thus, a community-scale conservation strategy may be more valuable in some settings. We describe communities of primary (primates) and secondary (dung beetles) seed dispersers from 5 sites in the Brazilian Amazon. We estimate community biomass of these taxa and, using multivariate ordination, examine the potential for natural reforestation at each site, given the communities of seed dispersers present. Since disturbed habitat is increasingly common and increasingly the focus of conservation efforts, we also examine differences among seed disperser communities between primary forest and secondary growth at each site. Analyses of faunal biomass in different localities and habitats indicate that secondary growth receives nearly as much use by primates as primary forest; given the dominant groups of dung beetles in secondary growth, disturbed habitat should show a pattern of seed burial that is clumped and deep. Areas with high biomass of Alouatta spp. and the large nocturnal dung beetle species may have the greatest potential for natural reforestation of secondary growth particularly for large seeded species. The data suggest that knowledge of the biomass of primary and secondary dispersing fauna facilitates predictions for the likelihood of disturbed habitat to regenerate and comparisons of sites in broader geographical areas e.g., Neotropical vs. Paleotropical forests.

Bat Activity at Woodland/Farmland Interfaces in Central Delaware

Abstract Bats vary their activity with different features of habitat, resource availability, predation risk, and other factors. Agricultural fields may provide an abundance of insect prey, but are also risky habitats due to their exposure. How bats use mixed landscapes is important information for biologists, as increasing development affects the amount of suitable habitat and impacts bat populations in the region. Using acoustic recording, we monitored relative bat activity in open areas and edges of the woodland/farmland interface of agricultural fields in Kent County, DE. We examined bat activity among different sites, in openings versus edges, among crop types, relative to nearby forest fragment size and shape, and under different weather conditions. Bat activity was significantly higher along edges than in the open in the agricultural fields for passes/night, but we found no differences among crop types or sites and no interaction effects. We also found no effect of size or amount of edge of a fragment on bat activity. We found significant negative correlations between passes and temperature and wind speed, and significant positive correlations between passes and relative humidity and barometric pressure. Bats use agricultural areas for foraging, and the woodland interfaces along these fields are important for bat activity. This study provides data that may help engender conservation practices, such as retention of forested edges and maintenance of tree lines, and perhaps crop selection and pest control management, in the regions farming community.

Dung Beetles and Long-Term Habitat Fragmentation in Alter do Chão, Amazônia, Brazil

We examined the abundance and diversity of dung beetles in forest fragments within a savanna landscape near Alter do Chão, Pará, Brazil. These fragments have existed for 150 years and possibly millennia. Using pit-fall traps to capture dung beetles, we investigated fragment area, fragment isolation, and tree density in fragments as predictors of species richness, abundance, and biomass of dung beetles. Across six fragments, isolation distance was negatively related with dung beetle species richness, while all other variables were unrelated. We also examined the abundance of the dominant species using flight-intercept traps in 21 fragments. Tree density correlated negatively with abundance of the dominant species, a probable new species.

Arboreal Foraging Height in a Common Neotropical Dung Beetle, Canthon subhyalinus Harold (coleoptera: Scarabaeidae)

Abstract Arboreal foraging by dung beetles has been reported from tropical rainforests in several regions. In the central Amazon, Brazil, the widespread, arboreal dung beetle Canthon subhyalinus Harold was caught most often in dung traps at 8–24 m above the forest floor, below the height of most primate activity in the area, where dung should be plentiful yet competition for it low. Studies of dung beetle diversity routinely only include traps set on the forest floor, missing arboreal species such as C. subhyalinus, and generating misleading descriptions of dung beetle diversity and abundance. Future studies of dung beetle diversity should include arboreal traps to accurately sample the diversity and abundance of species that rarely forage at ground level.

Measuring Regal Fritillary Butterfly (Speyeria idalia) Habitat Requirements in South-Central Pennsylvania: Implications for the Conservation of an Imperiled Butterfly

Abstract To understand the habitat components that contribute to the presence of populations of a rare butterfly, we examined the abundance of critical plant-components of old fields that support some of the last remaining Eastern Speyeria idalia (Regal Fritillary Butterfly) subpopulations at Fort Indiantown Gap (FTIG), a National Guard training facility in south-central Pennsylvania. We compared densities of larval-host plants (Viola spp. [violets]), adult-nectar plants (Asclepias spp. [native milkweeds] and Cirsium spp. [thistles]), and native, tussock-forming, warm-season bunch grasses that provide protective resting and pupation sites in fields occupied by the butterfly and in nearby fields that were unoccupied. We found no significant difference in violet density among sites. Fields with Regal Fritillary Butterfly populations had significantly more nectar-plant flowering structures and greater bunch-grass percent cover. Grassland habitat occupied by Regal Fritillaries was characterized by a violet density of at least 1.55 plants/m2 and particular varieties of flowering nectar-plants available throughout the June–September flight period. Bunch grasses were also important to persistence of Regal Fritillaries; occupied sites had 20–45% bunch-grass cover and tussock formation. Understanding the habitat needs of this rare butterfly in Pennsylvania is vital to its restoration and reintroductions of the eastern form in the mid-Atlantic and northeastern US.

Lepidoptera of Fort Indiantown Gap National Guard Training Center, Annville, Pennsylvania

Abstract Eighty-one species of butterflies and two-hundred and thirty-seven species of moths were identified from Fort Indiantown Gap, a National Guard training facility in south-central Pennsylvania. The Lepidoptera found here include the last remaining population of Speyeria idalia idalia (eastern regal fritillary), as well as the rare Callophrys irus (frosted elfin), Hesperia leonardus (Leonards skipper), Datana ranaeceps (hand-maid moth), Zale sp. 1 nr. lunifera (Pine Barrens zale), and Anisota stigma (spiny oakworm moth). This habitat has a large and diverse Lepidoptera fauna, most likely due to periodic disturbance in some areas, conservation efforts to maintain native grassland, and a diverse plant community.

Possible Impact of Multiflora Rose on Breeding-Bird Diversity in Riparian Forest Fragments of Central Delaware

Abstract The populations of many North American forest-breeding songbirds have declined over the past few decades, initiating much research regarding the factors influencing avian use of remaining forests, many of which are highly disturbed and impacted by invasive plants. Our objective was to compare the species richness of breeding birds in riparian forest fragments that contain different amounts of the invasive shrub, Rosa multiflora (Multiflora Rose). We conducted 20 point counts in each of three sites from early June until mid-July of 2008 and 2009, and estimated species richness and relative richness using the program COMDYN4. During 2008, species richness was lower at the site with the most Multiflora Rose. However, the number of species at that site increased by 33% from 2008 to 2009, whereas the number of species in the other two sites remained similar. Consequently, we did not detect differences in species richness among sites during 2009. Despite the increase in species richness at the more heavily invaded site, several common ground- to shrub-nesting species did not occur at that site during either year. Multiflora Rose may reduce the species richness of breeding birds in forest fragments, but additional research coinciding with the control and removal of this invasive shrub will be needed to infer such a relationship.