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Westborough, MA, United States

Charney N.D.,Bryn Mawr College | Kubel J.E.,Natural Heritage and Endangered Species Program
PLoS ONE | Year: 2015

Improving detection rates for elusive species with clumped distributions is often accomplished through adaptive sampling designs. This approach can be extended to include species with temporally variable detection probabilities. By concentrating survey effort in years when the focal species are most abundant or visible, overall detection rates can be improved. This requires either long-term monitoring at a few locations where the species are known to occur or models capable of predicting population trends using climatic and demographic data. For marbled salamanders (Ambystoma opacum) in Massachusetts, we demonstrate that annual variation in detection probability of larvae is regionally correlated. In our data, the difference in survey success between years was far more important than the difference among the three survey methods we employed: diurnal surveys, nocturnal surveys, and dipnet surveys. Based on these data, we simulate future surveys to locate unknown populations under a temporally adaptive sampling framework. In the simulations, when pond dynamics are correlated over the focal region, the temporally adaptive design improved mean survey success by as much as 26% over a non-adaptive sampling design. Employing a temporally adaptive strategy costs very little, is simple, and has the potential to substantially improve the efficient use of scarce conservation funds. © 2015 Charney et al. Source

Jones M.T.,Natural Heritage and Endangered Species Program | Jones M.T.,University of Massachusetts Amherst | Patterson III W.A.,University of Massachusetts Amherst
Rhodora | Year: 2011

We studied the influence of local site characteristics on the abundance of Equisetum scirpoides, a regionally rare, circumboreal species, at five sites in the Deerfield River watershed of Massachusetts, near the southern edge of its range. Equisetum scirpoides was most abundant on north- to northeast-facing, steep slopes (22-34°), with low total basal area (TBA) and small stem size. While E. scirpoides was always found in association with Tsuga canadensis, plots with high-density E. scirpoides were associated with lower Tsuga TBA than "low density/absent" plots. Average Tsuga and deciduous stem diameter at breast height within "high density" plots was significantly lower than in "low density/absent" plots. Our results suggest that E. scirpoides is unlikely to occur on south-facing slopes and, where it occurs on north-facing slopes, it requires low deciduous canopy cover and frequent disturbance, which exposes mineral soil. Equisetum scirpoides was absent from several similar habitats (i.e., with northerly aspect, steep slopes, clay substrate, Tsuga canopy, and massive bank failure) within the study watershed, suggesting that it has low dispersal capability at that scale. © 2011 New England Botanical Club. Source

It has long been suspected that Grammia oithona may be a form of G. phyllira, but concrete evidence has been lacking. The only obvious difference between G. oithona and G. phyllira is the presence of cream-colored scales outlining the veins of the forewing of G. oithona. A female G. oithona from Hampden County, Massachusetts, U.S.A., produced progeny consisting of 55 phyllira and 51 oithona. The following year a female G. phyllira from the same locality produced 33 phyllira and 40 oithona. Therefore the name oithona represents a wing pattern phenotype, not a species, at least in the population studied. Progeny of both wild females were bred in captivity, each cross consisting of a virgin female bred with a single male, with eight separate crosses producing offspring. The simplest, most parsimonious hypothesis consistent with the data from all eight crosses is that the wing pattern phenotype is inherited as a single autosomal gene with two alleles, a dominant phyllira allele and a recessive oithona allele; dominance may be incomplete in heterozygotes. Assuming G. phyllira and G. oithona to be conspecific across their composite range, the phyllira phenotype occurs with high frequency in most populations along the East Coast and in the Upper Midwest, and with low frequency in most populations to the west and south of this range. C. phyllira is of conservation concern in the northeastern U.S.A., where it has declined substantially during the past 50 to 100 years. The natural history of G. phyllira is typical of Grammia species, but its dependence on grassland and savanna habitat on dry, sandy soils is an important consideration in conservation and management efforts for this species. Source

Maxted A.M.,University of Georgia | Maxted A.M.,New York State Department of Health | Porter R.R.,800 Quinard Court | Luttrell M.P.,University of Georgia | And 5 more authors.
Avian Diseases | Year: 2012

The population of ruddy turnstones (Arenaria interpres morinella) that migrates through Delaware Bay has undergone severe declines in recent years, attributable to reduced availability of horseshoe crab (Limulus polyphemus) eggs at this critical spring migration stopover site. Concurrently, this population has experienced annual low pathogenicity avian influenza virus (AIV) epidemics at this same site. Using a prospective cohort study design with birds individually flagged during MayJune 20062008, we evaluated resighting rates (a proxy for annual survival) between AIV-infected and uninfected birds at 1 yr after capture, testing, and measurement. Overall resighting rate was 46, which varied by year and increased with relative mass of the bird when captured. Resighting rates were not different between AIV-infected and uninfected birds in any period. In multivariate analyses, infection status was also unrelated to resighting rate after controlling for year, day, state, sex, body size, mass index, or whether the bird was blood-sampled. Thus, apparent annual survival in ruddy turnstones was not reduced by AIV infection at this migratory stopover. However, it is unknown whether intestinal AIV infection might cause subtle reductions in weight gain which could negatively influence reproduction. © American Association of Avian Pathologists. Source

Nelson M.W.,Natural Heritage and Endangered Species Program
Journal of the Lepidopterists' Society | Year: 2012

Hadena ectypa (Morrison, 1875) (Noctuidae: Noctuinae: Hadenini) is a rarely encountered moth of conservation concern, inhabiting forest and woodland openings and edges in eastern North America. A population discovered in 2002 in Massachusetts (USA) is the first record of this species in New England. Hadena ectypa larvae from this population were reared in 2003, 2009, and 2010; the immature stages and life history are described. Parasitism by a species of Eulophus Geoffroy, 1762 (Hymenoptera: Eulophidae) and predation by Toxomerus geminatus (Say, 1823) (Diptera: Syrphidae) were observed. The native host plant of Hadena ectypa is Silene stellata (L.) W.T. Aiton (Caryophyllaceae), however, the population in Massachusetts uses introduced Silene vulgaris (Moench) Garcke as the primary larval host. Hadena ectypa could have adopted S. vulgaris as a novel host at any time during the past 200 years. S. vulgaris shares a number of traits with S. stellata that may have facilitated this host shift. Many of these traits are also shared by another introduced species, Silene latifolia Poiret, and while Hadena ectypa will feed on this plant in captivity, is not known to use it in the wild. The adoption of S. vulgaris as a larval host may allow Hadena ectypa to spread to new, weedier habitats, to increase its geographic range, and to increase its propensity for a second annual generation. Source

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