Sites In New England Research Articles

Host-utilization differences between larval and nymphal deer ticks in northeastern U.S. sites enzootic for Borrelia burgdorferi sensu stricto

In the northeastern U.S., Borrelia burgdorferi sensu stricto, the agent of Lyme disease, is maintained between vertebrate hosts and subadult deer ticks (the northern clade of Ixodes scapularis, formerly known as Ixodes dammini). Theoretical arguments suggest that the force of transmission would be greatest when infected nymphal ticks focus their bites on the same host as the uninfected larvae. Stage-specific differences in host utilization would reduce the force of transmission, but to date such differences remain understudied. We determined the host utilization differences of larval and nymphal deer ticks using bloodmeal analysis of host-seeking nymphs and adults collected from 5 field sites in New England. Matched cohorts of ticks (nymphs=506, adults=451), i.e. ticks that had fed during the same summer season, were used to control for yearly host population variations. Infection status of all ticks was determined by real time PCR. Nymphal deer ticks were more likely to have fed on birds and sciurids (13% vs 3%, and 41% vs 9%, respectively p<0.001) and larvae were more likely to have fed on shrews (26% vs 3%, p<0.001). Similarly, ticks that had fed on a mouse or a shrew as larvae were likely to become infected (OR= 3.195, 95% CI [1.9, 5.1] and OR=2.5[1.6,3.8] respectively), and they were positively associated with infection prevalence at our sites. However, very few nymphs fed on shrews, and they were not associated with infection, raising the question of how uninfected shrews acquire infection each year. Sciurids did not appear to contribute to the enzootic cycle at our sites, which may be due to the low numbers of larvae that fed on them. Sciurid-fed ticks of either stage were not associated with infection. Both stages of ticks were less likely to be infected if they had fed on deer (OR=0.08 [0.02.0.3] and OR=0.4 [0.2,0.7] tested as nymphs and adults, respectively) and thus deer likely served to reduce the force of transmission at our sites. Site-specific analysis of differential host utilization by subadult deer ticks may contribute to appropriate targeting of interventions and thereby promote reducing risk of acquiring Lyme disease and the other deer tick-transmitted infections.

Passive acoustic monitoring of biological soundscapes in a changing climate

Passive acoustic monitoring of biological soundscapes offers a long-term view into ecosystem state. This is particularly well studied for coral reefs and tropical littoral systems with evidence for similar capability in temperate and deep ocean biologically rich ecosystems. Monitoring ecosystem state under both climate change impacts and changing human usage is a critical piece of understanding how climate change and human use impact ecosystems. Passive acoustics allow for wide area coverage of an ecosystem heartbeat, and changes in key bioacoustic metrics in coral reefs indicate shifts from healthy coral dominated systems to more degraded systems with increased macroalgal cover. These shifts are typically associated with increased ocean temperatures and/or increased human use. The primary controls on coral reef soundscapes are time of day and year. Here, broad comparisons between warmer and cooler years at long term coral reef monitoring sites in Hawaii will be discussed, as well as summer versus winter biological soundscapes at temperate sites in New England. Reef soundscapes encompass contributions from a wide variety of marine flora and fauna, some of which can be identified to species level through characteristic calls and tracked with a high degree of fidelity through passive acoustics alone.

Smartphone Ownership, Smartphone Utilization, and Interest in Using Mental Health Apps to Address Substance Use Disorders: Literature Review and Cross-sectional Survey Study Across Two Sites.

BackgroundIn recent years, there has been increasing interest in implementing digital technologies to diagnose, monitor, and intervene in substance use disorders. Smartphones are now a vehicle for facilitating telepsychiatry visits, measuring health metrics, and communicating with health care professionals. In light of the COVID-19 pandemic and the movement toward web-based and hybrid clinic visits and meetings, it has become especially salient to assess phone ownership among individuals with substance use disorders and their comfort in navigating phone functionality and using phones for mental health purposes.ObjectiveThe aims of this study were to summarize the current literature around smartphone ownership, smartphone utilization, and the acceptability of using smartphones for mental health purposes and assess these variables across two disparate substance use treatment sites.MethodsWe performed a focused literature review via a search of two academic databases (PubMed and Google Scholar) for publications since 2007 on the topics of smartphone ownership, smartphone utilization, and the acceptability of using mobile apps for mental health purposes among the substance use population. Additionally, we conducted a cross-sectional survey study that included 51 participants across two sites in New England—an inpatient detoxification unit that predominantly treats patients with alcohol use disorder and an outpatient methadone maintenance treatment clinic.ResultsPrior studies indicated that mobile phone ownership among the substance use population between 2013 and 2019 ranged from 83% to 94%, while smartphone ownership ranged from 57% to 94%. The results from our study across the two sites indicated 96% (49/51) mobile phone ownership and 92% (47/51) smartphone ownership among the substance use population. Although most (43/49, 88%) patients across both sites reported currently using apps on their phone, a minority (19/48, 40%) reported previously using any apps for mental health purposes. More than half of the participants reported feeling at least neutrally comfortable with a mental health app gathering information regarding appointment reminders (32/48, 67%), medication reminders (33/48, 69%), and symptom surveys (26/45, 58%). Most patients were concerned about privacy (34/51, 67%) and felt uncomfortable with an app gathering location (29/47, 62%) and social (27/47, 57%) information for health care purposes.ConclusionsThe majority of respondents reported owning a mobile phone (49/51, 96%) and smartphone (47/51, 92%), consistent with prior studies. Many respondents felt comfortable with mental health apps gathering most forms of personal information and with communicating with their clinician about their mental health. The differential results from the two sites, namely greater concerns about the cost of mental health apps among the methadone maintenance treatment cohort and less experience with downloading apps among the older inpatient detoxification cohort, may indicate that clinicians should tailor technological interventions based on local demographics and practice sites and that there is likely not a one-size-fits-all digital psychiatry solution.

Urinary biomonitoring of occupational exposures to Bisphenol A Diglycidyl Ether (BADGE) - based epoxy resins among construction painters in metal structure coating.

Epoxy resin systems based on Bisphenol A Diglycidyl Ether (BADGE) monomer and its higher oligomers are important commercial formulations used widely in construction for protective coating of steel structures, such as bridges. The literature on occupational exposures and biomonitoring of BADGE-based epoxies among construction painters is remarkably limited. In this first occupational biomonitoring study of epoxies, 44 construction painters performing mid- and top-coating were recruited from 12 metal structure coating sites in New England. Cross-shift changes in the urinary levels of total BADGE and its three major hydrolysis derivatives - BADGE·2H2O, BADGE·H2O, BADGE·HCl·H2O - were assessed. Results for 81 urine samples collected from coating workers were compared with 28 urine samples of a reference group of 14 spray polyurethane foam (SPF) insulation workers. The highest concentrations of all biomarkers were found in the urine samples of mid-coat applicators. The major urinary biomarker of BADGE in this cohort of workers, BADGE·2H2O, was detected in 100% of urine samples. The post-shift BADGE·2H2O (specific gravity normalized data) in mid-coat applicators had a geometric mean (GM) of 1.46ng/mL and a geometric standard deviation (GSD) of 3.6 (range, 0.2-18.7ng/mL). The second most abundant biomarker in urine, BADGE·HCl·H2O, was measured in 84% of samples, and had a post-shift GM(GSD) of 0.17 (2.3) ng/mL (range, <0.025-0.59ng/mL). BADGE·2H2O was 8.6 times more abundant than BADGE·HCl·H2O. BADGE·H2O was quantified only in 10% of the samples (range, 0.11-0.41ng/mL). Free BADGE in post-shift urine, corrected for background, had GM (GSD) of 0.04 (2.5) ng/mL (range, <0.025-0.16ng/mL). Urinary BADGE·2H2O were significantly higher (p=0.01) in mid-coat applicators compared to top-coat and SPF workers. Post-shift urinary BADGE·2H2O in mid-coat applicators increased by ~2.9× (p=0.02) and 1.36× in top-coat applicators (p=0.18) compared to pre-shift values, but not in SPF workers (0.95×; p=0.40). In conclusion, we demonstrate that (i) significant BADGE uptake occurs via inhalation and skin exposures during application of epoxy-containing paintings (mid-coat), suggesting the need for improvements in hygiene practices and personal protective measures; (ii) BADGE·2H2O is a robust and sensitive biomarker for biomonitoring of exposures to BADGE-based epoxies in occupational settings; and (iii) widespread occurrence of BADGE and BADGE·2H2O in the urine of all workers, including SPF workers, suggest common exposures from non-occupational sources, such as ingestion or do-it-yourself consumer applications of epoxy resins. In light of this observation, establishing a reliable biological monitoring guidance value (BMGV) for BADGE·2H2O will require more background biomonitoring and health effect data. An initial reference value for BADGE·2H2O of 0.5ng/mL (SG-normalized) or 180nmol/mol creatinine is being proposed as the threshold to discriminate occupational from non-occupational exposures based on the maximum values observed in the reference SPF group.

Intra-Meadow Variation in Seagrass Flowering Phenology Across Depths

Variation in the timing of sexual reproduction, as well as differences in the relative investment in asexual vs sexual reproduction, commonly occurs among populations. Less is known about such variation within populations, yet small-scale differences in phenology and reproductive investment have the potential to limit gene flow and consequently the adaptive capacity of populations. We examined within-site variation in sexual reproduction in seagrasses, marine angiosperms that can reproduce asexually via clonal propagation or sexually via flowering, and that form the foundation of critical marine ecosystems globally. Many factors, including light availability, temperature, nutrient availability, and genetic identity, influence the rate and timing of seagrass flower development, yet little is known about how phenology varies across common environmental gradients within individual seagrass meadows. Here, we investigate how the density, morphology, and phenology of eelgrass (Zostera marina) differs across depths within multiple sites in New England. Despite variation in the proportion of reproductive vs vegetative shoots across sites, reproductive investment did not differ across depths within sites. However, a comparison of developmental stages of flowering shoots revealed delays in flower development for deep plants compared with shallow plants for all sites, demonstrating a consistent offset in reproductive phenology across depths. Our results suggest that differences in the timing of flowering may limit gene flow across seagrass meadows, with the potential for repeated genetic divergence in eelgrass populations spanning a depth gradient.

Assessment and control of exposures to polymeric methylene diphenyl diisocyanate (pMDI) in spray polyurethane foam applicators.

In this work we characterize personal inhalation and dermal exposures to diphenyl methane diisocyanate (MDI) and other species in polymeric MDI (pMDI) formulations during spray polyurethane foam (SPF) insulation at 14 sites in New England. We further assess the adequacy of current workplace practices and exposure controls via comparative urinary biomonitoring of the corresponding methylene diphenyl diamine (MDA) pre- and post-shift. MDI and pMDI are potent dermal and respiratory sensitizers and asthmagens, strong irritants of the skin, eyes, and the respiratory tract, and may cause skin burns. This study is the first comprehensive report to-date on the work practices, inhalation and dermal exposures to isocyanates and effectiveness of existing controls during SPF applications. Breathing zone exposures to 4,4' MDI (n = 31; 24 sprayers, 7 helpers) ranged from 0.9 to 123.0 μg/m3 and had a geometric mean (GM) of 13.8 μg/m3 and geometric standard deviation (GSD) of 4.8. Stationary near field area samples (n = 15) were higher than personal exposures: GM, 40.9 (GSD, 3.9) μg/m3, range 1.4-240.8 μg/m3. Sixteen percent of personal air samples and 35% of area samples exceeded the National Institute for Occupational Health and Safety's (NIOSH) full shift recommended exposure limit (REL) of 50 μg/m3, assuming zero exposure for the unsampled time. 4,4' MDI load on the glove dosimeters had a GM of 11.4 (GSD 2.9) μg/glove pair/min, suggesting high potential for dermal exposures. Urinary MDA had a GM of 0.7 (GSD, 3.0) μmol MDA/mol creatinine (range, nd-14.5 μmol MDA/mol creatinine). Twenty-five % of urine samples exceeded the Health and Safety Executive (HSE) biological monitoring guidance value (BMGV) of 1 μmol MDA/mol creatinine. We further report on field observations regarding current exposure controls, discuss implications of these findings and opportunities for improving work practices to prevent isocyanate exposures during SPF insulation.

Entangled Things and Deposits in Early Colonial Native New England

We consider the entanglement of objects and deposits at an early colonial-period Native American site in New England’s middle Connecticut River valley. We examine the acquisition, circulation, and deposition of archaeological materials and consider the obligations, reciprocities, and networks maintained and reworked by Pocumtuck people and their native and nonnative neighbors. The archaeological evidence indicates increasingly circumscribed networks as stone, copper, clay, shell, and glass created debts, obligations, and duties between individuals and communities. The Pocumtuck, along with their kin and allies, were entangled in colonialism as active co-producers of social transformation.

Climate change: potential impacts on frost–thaw conditions and seasonal load restriction timing for low-volume roadways

Low-volume roads constitute a major percentage of roadways around the world. Many of these are located in seasonal frost areas where agencies increase and decrease the allowable weight limits based on seasonal fluctuations in the load carrying capacity of the roadway due to freeze–thaw conditions. As temperatures shift due to changing climate, the timing and duration of winter freeze and spring thaw periods are likely to change, potentially causing significant impacts to local industry and economies. In this study, an ensemble of 19 climate models were used to project future temperature changes and the impact of these changes on the frost depth and timing of seasonal load changes across five instrumented pavement sites in New England. The study shows that shifts of up to 2 weeks are projected at the end of the century and that moderate variability was observed across the study region, indicating that local conditions are important for future assessments depending on the desired level of accuracy. From 1970 to 1999, the average freezing season lasted between 9 and 13 weeks in the study region. By 2000–2029, the frozen period shortens by approximately 10 days over baseline duration (10–20% reduction). By the end of the century under RCP 4.5, frozen periods are typically shorter by 4 weeks or a 30–40% reduction. However, RCP 8.5 results indicate that four out of the five sites would have no frozen period during at least six winters from 2060 to 2089.

Bat Roosting in Bridges: Pros and Cons of Assessment Methods from a New England Regional Study

A research project was undertaken to assess bats’ use of bridges for roosting in New England. The project included rapid visual assessments of 191 bridges and more extensive evaluation of 18 of these bridges. Full evaluations included acoustic monitoring, detailed inspections, and emergence studies during early, mid-, and late summer roosting seasons in summer 2015, summer 2016, or both. During this project, 13 bridges were documented and positively identified as bat roosting sites in New England, and an additional two were highly likely (six of them were monitored in the project; 11 were identified by state departments of transportation), with possible roosting at several other sites. The project evaluated monitoring technologies including acoustic methods, infrared imaging, borescope inspection, and visual inspection. To identify bat species, both full-spectrum and zero-crossing acoustic monitoring software programs were used. These programs’ results differed significantly in species identification of identical call sequences; the range agreed with wide discrepancies between automated acoustic bat identification software program results previously reported in the literature. A new bridge inspection survey has been developed for the project to supplement FHWA-FRA survey forms. Recommendations for bridge surveys, training of inspection personnel, interpretation of data, and information to request from consultants have been developed through the project. Final project findings can be used as guidance for transportation agencies developing protocol for construction at potential roosting sites, which will be especially useful if federal listing of bat species and associated 4(d) rulings are modified in the future.

Concentrations and speciation of arsenic in New England seaweed species harvested for food and agriculture

A survey of arsenic (As) concentrations and speciation was conducted on 10 species of seaweed from commercial harvesters and from collection at two sites in New England. Concentrations of As ranged from 4 to 106 mg/kg, mostly in the form of arsenosugars, with the distribution of arsenosugar analogs varying between taxa. In brown algae, As levels were correlated with phosphate concentrations, and arsenosugar speciation reflected differences in sulfur and phosphate concentrations between taxa. Several samples of the brown algae species Laminaria digitata contained significant levels of inorganic As (2.8–20 mg/kg), the most toxic form of As. A weak acid extraction with microwave heating was compared with a weaker methanol: water extraction method, and found to give slightly higher extraction efficiency with comparable relative concentrations of inorganic As, supporting the use of this faster and simpler extraction method for monitoring. Seaweed is a niche dietary item in the U.S. but its popularity is increasing; it is also used in agriculture and livestock farming which provide potential indirect routes for human exposure. The presence of occasional high concentrations of iAs, as well as the lack of toxicity studies on organic As species, suggest that monitoring of these high As foods is warranted.

Metal Bioaccumulation by Estuarine Food Webs in New England, USA.

Evaluating the degree of metal exposure and bioaccumulation in estuarine organisms is important for understanding the fate of metals in estuarine food webs. We investigated the bioaccumulation of Hg, methylmercury (MeHg), Cd, Se, Pb, and As in common intertidal organisms across a watershed urbanization gradient of coastal marsh sites in New England to relate metal exposure and bioaccumulation in fauna to both chemical and ecological factors. In sediments, we measured metal and metalloid concentrations, total organic carbon (TOC) and SEM-AVS (Simultaneously extracted metal-acid volatile sulfides). In five different functional feeding groups of biota, we measured metal concentrations and delta 15N and delta 13C signatures. Concentrations of Hg and Se in biota for all sites were always greater than sediment concentrations whereas Pb in biota was always lower. There were positive relationships between biota Hg concentrations and sediment concentrations, and between biota MeHg concentrations and both pelagic feeding mode and trophic level. Bioavailability of all metals measured as SEM-AVS or Benthic-Sediment Accumulation Factor was lower in more contaminated sites, likely due to biogeochemical factors related to higher levels of sulfides and organic carbon in the sediments. Our study demonstrates that for most metals and metalloids, bioaccumulation is metal specific and not directly related to sediment concentrations or measures of bioavailability such as AVS-SEM.

0056 Patterns of Site-Employment of Construction Workers On and Off Commercial Construction Sites in New England and the Relationship to Musculoskeletal Pain

ObjectivesConstruction workers who work on multiple jobsites have a high prevalence of musculoskeletal disorders. Yet, scant quantitative information exists in the scientific literature on the relationship between worksite mobility patterns...

Chronic Natural Occurrence of Disseminated Neoplasia in Select Populations of the Soft-Shell Clam,Mya arenaria, in New England

Disseminated neoplasia, a diffuse tumor of the hemic system, is character- ized in many bivalve mollusks by hemolymph containing 1-100% mitotic hemocytes. Little is known about the onset and chronic distribution of neoplasia in populations of Mya arenaria (Soft-shell Clam), though studies have reported episodic exposure to environmental contaminants or an infectious agent as a potential cause of this dis- ease. Here we provide the first set of continuous data on neoplasia in Soft-shell Clams, from three sites in New England where sediments have been characterized regarding their granulometry, composition, contaminants, and clam densities. When correlat- ing sediment characteristics to terminal neoplasia (76-100% neoplastic or rounded, unattached hemocytes), New Bedford Harbor, MA, which is the most contaminated site, had the highest frequency of treminal neoplasia (maximum of 9.49% ± 0.78 SE), and the most pristine site, Ogunquit, ME, displayed the lowest frequencies (maximum of 0.47% ± 0.05 SE). Correlations of frequency of neoplasia to known environmental contaminants also suggests that fully neoplastic individuals were found only at sites of increased levels of heavy metals, PCBs, and PAHs. In addition, we documented the highest frequency of clams with terminal neoplasia from New Bedford Harbor in December (9.49% ± 0.78 SE) when seawater temperatures were low, and the lowest frequency in July (1.08 ± 0.4 SE) when seawater temperatures were highest. These results may indicate vulnerability of neoplastic clams to seasonal increases in environ- mental temperature and resulting oxidative stress. Based on shell measurements and a theoretical mathematical age model (which correlates susceptibility to neoplasia with age and sexual maturity), we suggest that the Soft-shell Clam is most susceptible to this disease between one and two years of age (9.5% frequency at 1 year, 22.25% inci- dence at 1.5 years, and 57.14% incidence at 2 years).

Barriers to Medical Provider Support for Prescription Naloxone As Overdose Antidote for Lay Responders

Poisonings are the leading cause of adult injury death in the United States. Over 12 weeks in 2011, 143 key informant interviews were conducted using a structured interview guide in three study sites in New England. This analysis focuses on the 24 interviews with emergency department providers, substance use treatment providers, pain specialists, and generalist/family medicine practitioners. Using an iterative coding process, we analyzed statements regarding support and concern about naloxone prescription for pain patients and drug users. The study's implications and limitations are discussed and future research suggested. The Centers for Disease Control and Prevention funded this study.

Corrigendum to &amp;quot;Speciated mercury at marine, coastal, and inland sites in New England – Part 2: Relationships with atmospheric physical parameters&amp;quot; published in Atmos. Chem. Phys., 12, 4181–4206, 2012

H. Mao1, R. Talbot2, J. Hegarty3, and J. Koermer4 1Department of Chemistry, State University of New York, College of Environmental Science and Forestry, Syracuse, NY 13210, USA 2Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA 3AER, Inc., 131 Hartwell Avenue, Lexington, MA, 02421, USA 4Department of Atmospheric Science & Chemistry, Plymouth State University, Plymouth, New Hampshire 03264, USA

Speciated mercury at marine, coastal, and inland sites in New England – Part 1: Temporal variability

Abstract. A comprehensive analysis was conducted using long-term continuous measurements of gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and particulate phase mercury (HgP) at coastal (Thompson Farm, denoted as TF), marine (Appledore Island, denoted as AI), and elevated inland (Pac Monadnock, denoted as PM) sites from the AIRMAP Observatories in southern New Hampshire, USA. Decreasing trends in background Hg0 were identified in the 7.5- and 5.5-yr records at TF and PM with decline rates of 3.3 parts per quadrillion by volume (ppqv) yr−1 and 6.3 ppqv yr−1, respectively. Common characteristics at these sites were the reproducible annual cycle of Hg0 with its maximum in winter-spring and minimum in fall, comprised of a positive trend in the warm season (spring – early fall) and a negative one in the cool season (late fall – winter). Year-to-year variability was observed in the warm season decline in Hg0 at TF varying from a minimum total (complete) seasonal loss of 43 ppqv in 2009 to a maximum of 92 ppqv in 2005, whereas variability remained small at AI and PM. The coastal site TF differed from the other two sites with its exceptionally low levels (as low as below 50 ppqv) in the nocturnal inversion layer possibly due to dissolution in dew water. Measurements of Hg0 at PM exhibited the smallest diurnal to annual variability among the three environments, where peak levels rarely exceeded 250 ppqv and the minimum was typically 100 ppqv. It should be noted that summertime diurnal patterns at TF and AI were opposite in phase indicating strong sink(s) for Hg0 during the day in the marine boundary layer, which was consistent with the hypothesis of Hg0 oxidation by halogen radicals there. Mixing ratios of RGM in the coastal and marine boundary layers reached annual maxima in spring and minima in fall, whereas at PM levels were generally below the limit of detection (LOD) except in spring. RGM levels at AI were higher than at TF and PM indicating a stronger source strength in the marine environment. Mixing ratios of HgP at AI and TF were close in magnitude to RGM levels and were mostly below 1 ppqv. Diurnal variation in HgP was barely discernible at TF and AI in spring and summer. Higher levels of HgP were observed during the day, while values that were smaller, but above the LOD, occurred at night.

Speciated mercury at marine, coastal, and inland sites in New England – Part 2: Relationships with atmospheric physical parameters

Abstract. Long-term continuous measurements of gaseous elemental mercury (Hg0), reactive gaseous mercury (RGM), and particulate phase mercury (HgP) were conducted at coastal (Thompson Farm, denoted as TF), marine (Appledore Island, denoted as AI), and elevated inland rural (Pac Monadnock, denoted as PM) monitoring sites of the AIRMAP Observing Network. Diurnal, seasonal, annual, and interannual variability in Hg0, RGM, and HgP from the three distinctly different environments were characterized and compared in Part 1. Here in Part 2 relationships between speciated mercury (i.e., Hg0, RGM, and HgP) and climate variables (e.g., temperature, wind speed, humidity, solar radiation, and precipitation) were examined. The best point-to-point correlations were found between Hg0 and temperature in summer at TF and spring at PM, but there was no similar correlation at AI. Subsets of data demonstrated regional impacts of episodic dynamic processes such as strong cyclonic systems on ambient levels of Hg0 at all three sites, possibly through enhanced oceanic evasion of Hg0. A tendency of higher levels of RGM and HgP was identified in spring and summer under sunny conditions in all environments. Specifically, the 10th, 25th, median, 75th, and 90th percentile mixing ratios of RGM and HgP increased with stronger solar radiation at both the coastal and marine sites. These metrics decreased with increasing wind speed at AI indicating enhanced loss of RGM and HgP through deposition. RGM and HgP levels correlated with temperature positively in spring, summer and fall at the coastal and marine locations. At the coastal site relationships between RGM and relative humidity suggested a clear decreasing tendency in all metrics from &lt;40% to 100% relative humidity in all seasons especially in spring, compared to less variability in the marine environment. The effect of precipitation on RGM at coastal and marine locations was similar. At the coastal site, RGM levels were a factor of 3–4 to two orders of magnitude higher under dry conditions than rainy conditions in all seasons. In winter RGM mixing ratios appeared to be mostly above the limit of detection (LOD) during snowfalls suggesting less scavenging efficiency of snow. Mixing ratios of HgP at the coastal and marine sites remained above the LOD under rainy conditions. Precipitation had negligible impact on the magnitude and pattern of diurnal variation of HgP in all seasons in the marine environment.

Mercury levels of Nelson’s and saltmarsh sparrows at wintering grounds in Virginia, USA

Nelson's and saltmarsh sparrows (Ammodramus nelsoni and A. caudacutus) have recently been recognized as separate species, and because of their limited distributions and the susceptibility of their wetland habitats to climate change, these two new species are of conservation concern. Both species are known to bioaccumulate mercury at breeding sites in New England, USA where their ranges overlap, with the saltmarsh sparrow reported to have twice the concentration of blood total mercury. In this study we sampled both species on their shared wintering grounds, and documented that mercury exposure is lower than that reported for the breeding range, with saltmarsh sparrow blood mercury 2.6 times higher than in Nelson's sparrow. Feather mercury, which is incorporated on the breeding grounds, confirmed that saltmarsh sparrows had incorporated 2.3 times more mercury than Nelson's sparrows during the previous breeding season. A comparison of stable isotopes of nitrogen and carbon suggests that the higher exposure of saltmarsh sparrows may be not due to feeding at a higher trophic level, as previously hypothesized, but rather could be related to a difference in the carbon source at the base of each species' food chain. This study, along with recently published data from both species on additional breeding and wintering grounds, provides a more complete picture of relative mercury exposure. Saltmarsh sparrows are exposed to mercury levels that warrant concern, with the highest exposure being during the breeding season. Areas set aside for the long-term conservation of this species should be carefully assessed for mercury bioaccumulation.

Canopy spectral invariants, Part 2: Application to classification of forest types from hyperspectral data

Many studies have been conducted to demonstrate the ability of hyperspectral data to discriminate plant dominant species. Most of them have employed the use of empirically based techniques, which are site specific, requires some initial training based on characteristics of known leaf and/or canopy spectra and therefore may not be extendable to operational use or adapted to changing or unknown land cover. In this paper we propose a physically based approach for separation of dominant forest type using hyperspectral data. The radiative transfer theory of canopy spectral invariants underlies the approach, which facilitates parameterization of the canopy reflectance in terms of the leaf spectral scattering and two spectrally invariant and structurally varying variables—recollision and directional escape probabilities. The methodology is based on the idea of retrieving spectrally invariant parameters from hyperspectral data first, and then relating their values to structural characteristics of three-dimensional canopy structure. Theoretical and empirical analyses of ground and airborne data acquired by Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) over two sites in New England, USA, suggest that the canopy spectral invariants convey information about canopy structure at both the macro- and micro-scales. The total escape probability (one minus recollision probability) varies as a power function with the exponent related to the number of nested hierarchical levels present in the pixel. Its base is a geometrical mean of the local total escape probabilities and accounts for the cumulative effect of canopy structure over a wide range of scales. The ratio of the directional to the total escape probability becomes independent of the number of hierarchical levels and is a function of the canopy structure at the macro-scale such as tree spatial distribution, crown shape and size, within-crown foliage density and ground cover. These properties allow for the natural separation of dominant forest classes based on the location of points on the total escape probability vs the ratio log–log plane.

Status ofCoccobiusnr.Fulvus(Hymenoptera: Aphelinidae), a Parasitoid of Euonymus Scale (Hemiptera: Diaspididae), 12–16 Years After Its Release in Massachusetts

From 1990 to 1995, a classical biocontrol pro gram was conducted in New England against an Asian scale, Unaspis euonymi (Comstock) (Hemi ptera: Diaspididae), which attacks landscape Eu onymus plants. Many Euonymus species are of Asian origin (Flint 1983) and widely planted as ornamentals (Gill et al. 1982). Collection of eu onymus scale natural enemies for release in the USA began in Korea (Drea & Hendrickson 1988; Hendrickson et al. 1991), but from 1990-1995 our laboratory collected additional species near Beijing, China (Van Driesche et al. 1998a), includ ing 2 predators (Chilocorus kuwanae Silvestri and Cybocephalus nr. nipponicus Endrody Younga) and 3 parasitoids (Coccobius nr. fulvus (Compere et Annecke), Encarsia nr. diaspidicola (Silvestri) and Aphytis sp.). Impacts of the 2 pred ators have been documented (Van Driesche et al. 1998b; Van Driesche & Nunn 2003). In 1991-1994, 3,862 adult C. nr. fulvus were re leased at 11 sites; 12,966 adults, nr. diaspidicola at 27 sites; and 801 adult Aphytis sp. at 5 sites in New England (mostly Massachusetts) (Van Drie sche et al. 1998a). By 1994, apparent establish ment (recovery in 1 subsequent year following re lease) had occurred for C. nr. fulvus and E. nr. di aspidicola. No next-year recoveries were made for Aphytis sp., the species released last and in small est numbers. No evidence of spread of any parasi toid was observed. In addition, a pre-existing cos mopolitan polyphagous aphelinid, Encarsia cit rina (Crawford), was observed in samples from Massachusetts. In 1991, it was detected at 44% of 79 sites in southern New England. In 1994, para sitism of dissected adult female euonymus scales by E. citrina, pooled by generation across 18 loca tions in Massachusetts, averaged 13.4% (n 2,174 scales) for the overwintered spring adults, 33.6% (n = 1,271 scales) for the summer generation, and 31.2% (n = 933 scales) for the fall generation. Our objectives here were (1) to sample for ex otic parasitoids of euonymus scale in western Massachusetts in 2006 and 2007 at their original release sites, (2) to sample non-release locations to detect parasitoid spread, and (3) to assess ef fects of exotic parasitoids on the pre-existing par asitoid E. citrina.