New expansions in old clades: population genetics and phylogeny of Gnatholepis species (Teleostei: Gobioidei) in the Pacific

Species of the reef goby genus Gnatholepis exhibit enormous geographic ranges with little evidence of population segregation detectable based on mitochondrial DNA. To determine if genetic differentiation is evident with more rapidly evolving markers, seven microsatellite loci were screened from the species Gnatholepis anjerensis and G. scapulostigma and population segregation was tested among fish from across the South Pacific. Both AMOVA and pairwise F _ST analyses showed that, in concordance with previous mitochondrial results, most genetic variance occurs within individual populations, as population differentiation is evident only over the largest distances (>3,700 km). This result is contrasted with previous studies demonstrating that despite their relatively long larval periods, some gobiid fishes exhibit population differentiation on small (<100 km) geographic scales. Coalescence analysis showed that current Pacific populations of these species originated in the Pleistocene, presumably related to sea level fluctuations associated with episodes of glaciation. However, rate analysis based on a phylogeny of Gnatholepis species indicates that the species themselves are much older, consistent with a complex history of rapid, short-term population contractions and expansions, with corresponding rapid dispersal.     

Patterns of mtDNA diversity in North Atlantic populations of the mussel Mytilus edulis

Patterns of (female) mitochondrial DNA diversity were investigated in the blue mussel Mytilus edulis. Mytilus edulis is a ubiquitous member of contemporary North Atlantic hard-substrate communities and well represented in studies of this region. Mytilus edulis was surveyed in North America and Europe, as well as mid-Atlantic sites in Greenland, Iceland, and the Faroe Islands. Mitochondrial DNA sequences revealed considerable population structure but no monophyly of haplotypes between any major regions. Coalescent analyses suggest that migration across the Atlantic Ocean has prominently been from North American source populations and that Greenland was colonized recently and exclusively from North America. In North America, there was support for two regional groups along the North American coastline. Surprisingly, we also found evidence of recombination between some Mytilus edulis and Mytilus galloprovincialis female mtDNA sequences, particularly in northern Europe. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at     

Genetic relatedness and space use in a behaviorally flexible species of marmot, the woodchuck (Marmota monax)

Solitary species show several patterns of space use and relatedness. Individuals may associate randomly or may live near female or male kin, often as a result of natal philopatry or dispersal patterns. Although usually described as solitary or asocial, woodchucks (Marmota monax) are behaviorally flexible marmots that exhibit greater sociality in some populations than others. I examined relationships between kinship, geographic distance, and home range overlap, as well as dispersal and philopatry, to determine the extent to which kin associated spatially. I used a combination of microsatellite DNA analysis, long-term behavioral observations, and radiotelemetry to test predictions that females, but not males, would associate with kin. Indeed, woodchucks lived closer and shared a greater proportion of their home range with more closely related animals. Overlap of females' and males' home ranges was positively correlated with kinship, and male–female dyads shared more area with closer kin. Most juveniles delayed dispersal beyond their first summer. Females often remained philopatric and settled near their natal range. Although males often dispersed as yearlings, some males also established territories within or immediately adjacent to their natal home ranges. A combination of factors can explain these spatial patterns, including high population density associated with the study site's location within a suburban environment, high dispersal costs, and abundant food. Thus, despite their asocial and solitary reputation, woodchucks displayed spatial patterns seen in other, more social species of ground-dwelling sciurids.     

WHO GETS CLEAN WATER? AID ALLOCATION TO SMALL WATER SYSTEMS IN PENNSYLVANIA1

ABSTRACT: Research on the condition of drinking water provision in the United States documents the inequitable financial impact of environmental regulations on small water systems (those serving 3,300 or fewer people). While a variety of federal and state financial assistance programs are available for water systems, few quantitative analyses have evaluated the success of these programs in alleviating the problems of small systems. A case study of the largest aid initiative for water supply infrastructure in Pennsylvania provides the empirical framework through which to analyze government funding opportunities for water systems. This study examines the allocation practices of the Pennsylvania Infrastructure Investment Authority (PENNVEST) to water systems of varying sizes. Utilizing data from PENNVEST applications and the Pennsylvania Department of Environmental Protection, the distribution of PENNVEST award recipients and denied applicants by size characteristics are compared. The study indicates that very small water systems (those serving 500 or fewer) do not apply for or receive funds with the same frequency as their larger counterparts. Understanding the allocation of awards from PENNVEST offers insight into the ability of small communities to access capital for water supply infrastructure.     

Mainstreaming risk reduction in urban planning and housing: a challenge for international aid organisations

The effects of 'natural' disasters in cities can be worse than in other environments, with poor and marginalised urban communities in the developing world being most at risk. To avoid post-disaster destruction and the forced eviction of these communities, proactive and preventive urban planning, including housing, is required. This paper examines current perceptions and practices within international aid organisations regarding the existing and potential roles of urban planning as a tool for reducing disaster risk. It reveals that urban planning confronts many of the generic challenges to mainstreaming risk reduction in development planning. However, it faces additional barriers. The main reasons for the identified lack of integration of urban planning and risk reduction are, first, the marginal position of both fields within international aid organisations, and second, an incompatibility between the respective professional disciplines. To achieve better integration, a conceptual shift from conventional to non-traditional urban planning is proposed. This paper suggests related operative measures and initiatives to achieve this change.     

Trace Element Concentrations and Bioindicator Responses in Tree Swallows from Northwestern Minnesota

Extremely high concentrations of cadmium (3.5 μg/g dry wgt.) and elevated concentrations of chromium (>10 μg/g dry wgt.) and mercury (1.6 μg/g dry wgt.) were reported in waterbird tissues at Agassiz National Wildlife Refuge in northwestern Minnesota in 1994. Tree swallows (Tachycineta bicolor) were studied during 1998–2001 at three drainages into the Refuge, two pools on the Refuge, and at a nearby reference location to document whether high levels of contaminants were still present, and if so to quantify the source and severity of the contamination. Trace elements were measured in tree swallow eggs, livers, and diet. Reproductive success and bioindicator responses were monitored. In 2000, water was drawn down on Agassiz Pool, one of the main pools on the Refuge. This presented an opportunity to evaluate the response of trace element concentrations in the diet and tissues of tree swallows after reflooding. High concentrations of trace elements were not detected in swallow tissues, nor were there differences among locations. Less than 20% of swallow samples had detectable concentrations of cadmium or chromium. Mercury concentrations were low and averaged <0.25 μg/g dry wgt. in swallow tissues. Trace elements, including mercury, did not increase in tree swallows following the 2000 drawdown at Agassiz Pool. Hatching success and survival of nestlings to 12 days-of-age for tree swallows on the Refuge were similar to the national average and consistent with background trace element concentrations. Bioindicator measurements were within the normal ranges as well.     

An ecological framework for contextualizing carnivore–livestock conflict

Carnivore predation on livestock is a complex management and policy challenge, yet it is also intrinsically an ecological interaction between predators and prey. Human–wildlife interactions occur in socioecological systems in which human and environmental processes are closely linked. However, underlying human–wildlife conflict and key to unpacking its complexity are concrete and identifiable ecological mechanisms that lead to predation events. To better understand how ecological theory accords with interactions between wild predators and domestic prey, we developed a framework to describe ecological drivers of predation on livestock. We based this framework on foundational ecological theory and current research on interactions between predators and domestic prey. We used this framework to examine ecological mechanisms (e.g., density-mediated effects, behaviorally mediated effects, and optimal foraging theory) through which specific management interventions operate, and we analyzed the ecological determinants of failure and success of management interventions in 3 case studies: snow leopards (Panthera uncia), wolves (Canis lupus), and cougars (Puma concolor). The varied, context-dependent successes and failures of the management interventions in these case studies demonstrated the utility of using an ecological framework to ground research and management of carnivore–livestock conflict. Mitigation of human–wildlife conflict appears to require an understanding of how fundamental ecological theories work within domestic predator–prey systems.     

How Los Angeles' Air Quality Policies Benefit Minorities

This paper examines how air pollution control policies will affect the welfare of the different races in Southern California. The paper adopts the concept of the Net Welfare Impact (NWI) function to measure how air quality improvements affect the welfare (monetary and non-monetary) of individual households. The core finding is that many of the benefits of air quality improvement are enjoyed by minorities, especially Latinos (and African-Americans and Asians to a lesser extent), whose household incomes tend to be lower and family size larger than the regional average, and who are more likely to live in the neighbourhoods that are currently polluted. Thus, because minorities have suffered more from dirty air, they are the major beneficiaries from implementation of clean air policies. This is the result of the Federal clean air mandate that dictates uniform standards for all metropolitan areas.