Powdermill Nature Reserve
Powdermill Nature Reserve
Deiner K.,California Academy of Sciences |
Deiner K.,University of California at Davis |
Lemmon A.R.,Florida State University |
Mack A.L.,Powdermill Nature Reserve |
And 3 more authors.
PLoS ONE | Year: 2011
New Guinea is a biologically diverse island, with a unique geologic history and topography that has likely played a role in the evolution of species. Few island-wide studies, however, have examined the phylogeographic history of lowland species. The objective of this study was to examine patterns of phylogeographic variation of a common and widespread New Guinean bird species (Colluricincla megarhyncha). Specifically, we test the mechanisms hypothesized to cause geographic and genetic variation (e.g., vicariance, isolation by distance and founder-effect with dispersal). To accomplish this, we surveyed three regions of the mitochondrial genome and a nuclear intron and assessed differences among 23 of the 30 described subspecies from throughout their range. We found support for eight highly divergent lineages within C. megarhyncha. Genetic lineages were found within continuous lowland habitat or on smaller islands, but all individuals within clades were not necessarily structured by predicted biogeographic barriers. There was some evidence of isolation by distance and potential founder-effects. Mitochondrial DNA sequence divergence among lineages was at a level often observed among different species or even genera of birds (5-11%), suggesting lineages within regions have been isolated for long periods of time. When topographical barriers were associated with divergence patterns, the estimated divergence date for the clade coincided with the estimated time of barrier formation. We also found that dispersal distance and range size are positively correlated across lineages. Evidence from this research suggests that different phylogeographic mechanisms concurrently structure lineages of C. megarhyncha and are not mutually exclusive. These lineages are a result of evolutionary forces acting at different temporal and spatial scales concordant with New Guinea's geological history. © 2011 Deiner et al.
McDermott M.E.,Powdermill Nature Reserve |
DeGroote L.W.,Powdermill Nature Reserve
PLoS ONE | Year: 2017
Advanced timing of both seasonal migration and reproduction in birds has been strongly associated with a warming climate for many bird species. Phenological responses to climate linking these stages may ultimately impact fitness. We analyzed five decades of banding data from 17 migratory bird species to investigate 1) how spring arrival related to timing of breeding, 2) if the interval between arrival and breeding has changed with increasing spring temperatures, and 3) whether arrival timing or breeding timing best predicted local productivity. Four of 17 species, all mid- to long-distance migrants, hatched young earlier in years when migrants arrived earlier to the breeding grounds (∼1:1 day advancement). The interval between arrival on breeding grounds and appearance of juveniles shortened with warmer spring temperatures for 12 species (1-6 days for every 1°C increase) and over time for seven species (1-8 days per decade), suggesting that some migratory passerines adapt to climate change by laying more quickly after arrival or reducing the time from laying to fledging. We found more support for the former, that the rate of reproductive advancement was higher than that for arrival in warm years. Timing of spring arrival and breeding were both poor predictors of avian productivity for most migrants analyzed. Nevertheless, we found evidence that fitness benefits may occur from shifts to earlier spring arrival for the multibrooded Song Sparrow. Our results uniquely demonstrate that co-occurring avian species are phenologically plastic in their response to climate change on their breeding grounds. If migrants continue to show a weaker response to temperatures during migration than breeding, and the window between arrival and optimal breeding shortens further, biological constraints to plasticity may limit the ability of species to adapt successfully to future warming. © 2017 McDermott, DeGroote.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
News Article | November 1, 2016
Architects’ growing affinity for glassy buildings has given the world better views, more natural light, sexier skylines—and a lot of dead birds. The US Fish and Wildlife Service estimates about 750 million birds perish annually flying into glass façades, which can be hard to distinguish from open airspace. The problem is so bad in some places that skyscraper owners hire workers to remove expired birds from the bottoms of their buildings. Guy Maxwell, a partner at New York-based Ennead Architects, is on a mission to mitigate this fowl holocaust. A bird lover his entire life, he first became aware of architecture’s deadly impact on avifauna 15 years ago, shortly after the completion of his firm’s Rose Center for Earth and Space at NYC’s American Museum of Natural History. The enormous glass cube afforded unimpeded views of the spherical Hayden Planetarium within, but was a deadly invisible barrier to birds. Maxwell has been working to protect feathered species ever since. Working with him is an informal circle of anti-collision advocates that includes members of the American Bird Conservancy, New York City Audubon, New Jersey Audubon, and the Bird Safe Glass Foundation. (“It really takes a gang of merry pranksters to pull this off,” says Maxwell.) Together, they’ve made progress on bird-safe research, bird-safe building regulations, bird-safe glass, and bird-safety awareness, spurring changes that have already had a large, ahem, impact. Among their recent accomplishments is the American Bird Conservancy’s creation of two avian research facilities—one at the Powdermill Nature Reserve, about an hour outside of Pittsburgh, the other inside a modified shipping container at the Bronx Zoo. (The Bronx tunnel’s design was overseen, in part, by Maxwell and his colleagues at Ennead’s research-intensive division, Ennead Lab.) Spearheaded by American Bird Conservancy Bird Collisions Campaign Manager Christine Sheppard, these testing tunnels are the only ones of their kind in the US, and allow researchers to investigate which glass treatments and lighting conditions birds will fly toward or avoid. They’ve learned, for instance, that birds won’t try to fly through vertical line patterns that are less than four inches apart, and that line patterns tend to be more effective at preventing collisions than dotted ones. Using this knowledge, Maxwell, Sheppard, and their confederates have consulted with glass manufacturers like Viracon, Guardian, Bendheim, and Arnold Glas to help produce products like ceramic frit patterns and UV coatings—treatments that are visible to birds and can alert them to the presence of dangerous physical barriers. The group’s biggest policy achievement came in 2011, when it partnered with the US Green Building Council to launch a LEED pilot credit #55 for incorporating “bird collision deterrence” into new buildings. The goal: Make buildings as visible to birds as possible, through glass technologies, exterior building treatments like screens and louvers, and decreased night lighting levels. Maxwell says it has since become LEED’s most popular pilot credit. Other victories include legislation (initiated by Golden Gate Audubon) in San Francisco, Oakland, and other Bay Area cities establishing citywide bird safe building standards. Mandatory and voluntary ordinances have been passed in New York, Minnesota, and Toronto, as well. Much of the team’s research is embodied in Ennead’s Bridge for Laboratory Sciences at Vassar College. The bridge-like classroom-cum-laboratory is a case study in bird-safe architecture. Vertical metal sunscreens cover its long, curving façade. Its windows are coated in Arnold Glas’s Ornilux, a UV coating visible only to birds, and various hues of ceramic fritting (the range of colors ensures that the lines are visible to birds from a variety of species). The concept of bird safety is changing architecture, Maxwell says. Exceptional bird-friendly designs have been completed across the country, from the fritted glass windows of Weiss Manfredi Architects’ Brooklyn Botanic Garden Visitor Center, to AJC Architects’ Tracy Aviary Visitor Center in Salt Lake City, which is fronted by fractured metal screens that keep birds from flying into its windows. “There’s generally an awareness of this problem now,” says Maxwell. “You see architects considering this when before they had no idea it was even a problem.” The public is becoming more aware of the problem, too. New York City Audubon has even created an online portal, called D-Bird, where people can report building-related bird mortalities. Meanwhile, Maxwell and his band of bird advocates are seeking funding to ramp up their research and advocacy. They would like to build several more labs along the east coast, fight for more bird-safety legislation, and see bird-friendliness become an automatic consideration for architects. “I’m amazed that there are still many people who don’t realize the enormity of the problem,” Maxwell says.
PubMed | Smithsonian Tropical Research Institute, University of America, Ohio State University and Powdermill Nature Reserve
Type: Journal Article | Journal: PloS one | Year: 2015
Anthropogenic disturbances often change ecological communities and provide opportunities for non-native species invasion. Understanding the impacts of disturbances on species invasion is therefore crucial for invasive species management. We used generalized linear mixed effects models to explore the influence of land-use history and distance to roads on the occurrence and abundance of two invasive plant species (Rosa multiflora and Berberis thunbergii) in a 900-ha deciduous forest in the eastern U.S.A., the Powdermill Nature Reserve. Although much of the reserve has been continuously forested since at least 1939, aerial photos revealed a variety of land-uses since then including agriculture, mining, logging, and development. By 2008, both R. multiflora and B. thunbergii were widespread throughout the reserve (occurring in 24% and 13% of 4417 10-m diameter regularly-placed vegetation plots, respectively) with occurrence and abundance of each varying significantly with land-use history. Rosa multiflora was more likely to occur in historically farmed, mined, logged or developed plots than in plots that remained forested, (log odds of 1.8 to 3.0); Berberis thunbergii was more likely to occur in plots with agricultural, mining, or logging history than in plots without disturbance (log odds of 1.4 to 2.1). Mining, logging, and agriculture increased the probability that R. multiflora had >10% cover while only past agriculture was related to cover of B. thunbergii. Proximity to roads was positively correlated with the occurrence of R. multiflora (a 0.26 increase in the log odds for every 1-m closer) but not B. thunbergii, and roads had no impact on the abundance of either species. Our results indicated that a wide variety of disturbances may aid the introduction of invasive species into new habitats, while high-impact disturbances such as agriculture and mining increase the likelihood of high abundance post-introduction.
McDermott M.E.,Powdermill Nature Reserve |
DeGroote L.W.,Powdermill Nature Reserve
Global Change Biology | Year: 2016
Climate change is influencing bird phenology worldwide, but we still lack information on how many species are responding over long temporal periods. We assessed how climate affected passerine reproductive timing and productivity at a constant effort mist-netting station in western Pennsylvania using a model comparison approach. Several lines of evidence point to the sensitivity of 21 breeding passerines to climate change over five decades. The trends for temperature and precipitation over 53 years were slightly positive due to intraseasonal variation, with the greatest temperature increases and precipitation declines in early spring. Regardless of broodedness, migration distance, or breeding season, 13 species hatched young earlier over time with most advancing >3 days per decade. Warm springs were associated with earlier captures of juveniles for 14 species, ranging from 1- to 3-day advancement for every 1 °C increase. This timing was less likely to be influenced by spring precipitation; nevertheless, higher rainfall was usually associated with later appearance of juveniles and breeding condition in females. Temperature and precipitation were positively related to productivity for seven and eleven species, respectively, with negative relations evident for six and eight species. We found that birds fledged young earlier with increasing spring temperatures, potentially benefiting some multibrooded species. Indeed, some extended the duration of breeding in these warm years. Yet, a few species fledged fewer juveniles in warmer and wetter seasons, indicating that expected future increases could be detrimental to locally breeding populations. Although there were no clear relationships between life history traits and breeding phenology, species-specific responses to climate found in our study provide novel insights into phenological flexibility in songbirds. Our research underscores the value of long-term monitoring studies and the importance of continuing constant effort sampling in the face of climate change. © 2016 John Wiley & Sons Ltd
Sagata K.,PNG Institute of Biological Research |
Mack A.L.,Powdermill Nature Reserve |
Wright D.D.,PNG Institute of Biological Research |
Lester P.J.,Victoria University of Wellington
Insectes Sociaux | Year: 2010
Tropical ant communities are frequently diverse, but highly patchy in nature. The availability of suitable nest sites may be a regulating force in structuring litter ant communities. Our aim was to examine ant resource utilization in naturally occurring twigs, and to modify the availability of these resources in order to quantify the influence of nest availability on ant communities in a Papua New Guinean forest. First, we compared ant communities that assemble in artificial twigs (drilled, wooden dowels), naturally occurring twigs, and the leaf litter. A total of 55 ant species were captured: 33 from the leaf litter, 29 from naturally occurring twigs, and only 12 from artificial nests. Significantly different communities formed in each of the three nest types. Second, we examined how the density of natural or artificial nest material influenced the ant abundance and species richness. Plots had between 5 and 96 potential nest sites. An average of only 11.2% of these twigs was colonized. Both species richness and the total abundance of adult ants were significantly positively correlated with increasing naturally occurring twig density. Conversely, increasing the availability of artificial nests from 5 to 20 per plot had no significant effect on the proportion of artificial nests colonized, species richness, or the colony size. We observed that ant species richness and abundance increased with natural twig density, at least for naturally occurring communities. But why so many twigs remain vacant and available for ant colonization remains unknown. Other biotic and abiotic factors likely influence the use of nesting habitat in these ant communities. © International Union for the Study of Social Insects (IUSSI) 2010.
Oppel S.,University of Alaska Fairbanks |
Mack A.L.,Powdermill Nature Reserve
Biotropica | Year: 2010
Most tropical trees produce fleshy fruits that attract frugivores that disperse their seeds. Early demography and distribution for these tree species depend on the effects of frugivores and their behavior. Anthropogenic changes that affect frugivore communities could ultimately result in changes in tree distribution and population demography. We studied the frugivore assemblage at 38 fruiting Elmerrillia tsiampaca, a rain forest canopy tree species in Papua New Guinea. Elmerrillia tsiampaca is an important resource for frugivorous birds at our study site because it produces abundant lipid-rich fruits at a time of low fruit availability. We classified avian frugivores into functional disperser groups and quantified visitation rates and behavior at trees during 56 canopy and 35 ground observation periods. We tested predictions derived from other studies of plant-frugivore interactions with this little-studied frugivore assemblage in an undisturbed rain forest. Elmerrillia tsiampaca fruits were consumed by 26 bird species, but most seeds were removed by eight species. The most important visitors (Columbidae, Paradisaeidae and Rhyticeros plicatus) were of a larger size than predicted based on diaspore size. Columbidae efficiently exploited the structurally protected fruit, which was inconsistent with other studies in New Guinea where structurally protected fruits were predominantly consumed by Paradisaeidae. Birds vulnerable to predation foraged for short time periods, consistent with the hypothesis that predator avoidance enhances seed dispersal. We identified seven functional disperser groups, indicating there is little redundancy in disperser groups among the regular and frequent visitors to this tropical rain forest tree species. © 2009 The Author(s). Journal compilation © 2009 by The Association for Tropical Biology and Conservation.
Murphy S.J.,Ohio State University |
Audino L.D.,Federal University of Lavras |
Whitacre J.,Powdermill Nature Reserve |
Eck J.L.,Ohio State University |
And 4 more authors.
Ecology | Year: 2015
Patterns of diversity and community composition in forests are controlled by a combination of environmental factors, historical events, and stochastic or neutral mechanisms. Each of these processes has been linked to forest community assembly, but their combined contributions to alpha and beta-diversity in forests has not been well explored. Here we use variance partitioning to analyze ~40 000 individual trees of 49 species, collected within 137 ha of sampling area spread across a 900-ha temperate deciduous forest reserve in Pennsylvania to ask (1) To what extent is site-to-site variation in species richness and community composition of a temperate forest explained by measured environmental gradients and by spatial descriptors (used here to estimate dispersal-assembly or unmeasured, spatially structured processes)? (2) How does the incorporation of land-use history information increase the importance attributed to deterministic community assembly? and (3) How do the distributions and abundances of individual species within the community correlate with these factors? Environmental variables (i.e., topography, soils, and distance to stream), spatial descriptors (i.e., spatial eigenvectors derived from Cartesian coordinates), and land-use history variables (i.e., land-use type and intensity, forest age, and distance to road), explained about half of the variation in both species richness and community composition. Spatial descriptors explained the most variation, followed by measured environmental variables and then by landuse history. Individual species revealed variable responses to each of these sets of predictor variables. Several species were associated with stream habitats, and others were strictly delimited across opposing north- and south-facing slopes. Several species were also associated with areas that experienced recent (i.e., <100 years) human land-use impacts. These results indicate that deterministic factors, including environmental and land-use history variables, are important drivers of community response. The large amount of ''unexplained'' variation seen here (about 50%) is commonly observed in other such studies attempting to explain distribution and abundance patterns of plant communities. Determining whether such large fractions of unaccounted for variation are caused by a lack of sufficient data, or are an indication of stochastic features of forest communities globally, will remain an important challenge for ecologists in the future. © 2015 by the Ecological Society of America.
Pearce T.A.,Carnegie Museum of Natural History |
Mulvihill R.S.,Powdermill Nature Reserve |
Porter K.A.,National Aviary
Nautilus | Year: 2012
We describe the discovery of two slugs, Arion subfusciis and Deroceras reticulatum, on living adult birds captured for banding at Powdermill Nature Reserve, Rector, Pennsylvania. The presence of slugs on birds suggests that bird transport might play a role in slug dispersal.
Hughes D.F.,University of Texas at El Paso |
Tegeler A.K.,Powdermill Nature Reserve |
Herpetological Conservation and Biology | Year: 2016
We examined turtle populations occupying eight artificial ponds in Westmoreland County, southwestern Pennsylvania, USA. Beginning in 2005, we used sardine-baited hoop-nets to trap turtles for eight consecutive years at one pond. In 2013, we expanded sampling to include seven additional ponds near the primary study pond. We deployed and checked traps during two 5-d periods at all eight ponds, once in June and again in July 2013. Two of the 12 turtle species native to Pennsylvania were detected, Common Snapping Turtle (Chelydra serpentina serpentina; n = 53) and Midland Painted Turtle (Chrysemys picta marginata; n = 70). We found the Common Snapping Turtle at all surveyed ponds and its abundance was associated with larger, sparsely vegetated ponds. We found the Midland Painted Turtle at six of the eight surveyed ponds and its abundance was associated with smaller, heavily vegetated, ponds. Juveniles of both species were distributed differently than adults and were most common in shallow, heavily vegetated ponds with low visibility and were absent or nearly so from deep ponds with little emergent vegetation favored by adults. Across eight years, the number of juveniles was low or they were absent from the primary study pond, yet recruitment was likely maintained through a nearby nursery pond favored by juveniles. In this heterogeneous pond matrix, turtle population structures were strongly influenced by certain physical features of the ponds to the benefit of one life stage over another. Species composition was influenced in a likewise manner. Inter-pond movements were likely encouraged by local habitats and resident population structures. We suggest that ponds can be constructed or modified to accommodate one or more life stages of these turtle species, and enhance opportunity for pond colonization and gene flow among ponds. © 2016. Daniel F. Hughes. All Rights Reserved.