To mitigate the unintended consequences of roads and habitat fragmentation, biologists model wildlife corridors with least-cost path (LCP) analysis of spatial data managed with geographic information systems. However, the ability of LCP models to accurately predict preferred movement corridors remains questionable. We tested the effectiveness of an LCP model constructed using literature review, expert opinion, and the relative distribution of land-cover types present at roadside observations of Martes pennanti (Fisher). The model was then used to predict road-crossing corridors of Fishers, Lynx rufus (Bobcat), and Ursus americanus (American Black Bear) within our study area in northern New Hampshire. Roadside data were collected through track surveys from 5 Dec 2005–25 May 2006. Our analysis demonstrated that least-cost modeling successfully identified roadside wildlife corridors for Fishers and Bobcats, but not for American Black Bears.

Lontra canadensis (River Otter) have been reintroduced throughout much of their former range in North America, but our understanding of the function they serve in ecosystems to which they have been reintroduced remains incomplete. We examined the winter diet of reintroduced River Otters in Kentucky based on contents of 126 stomachs collected over three trapping seasons, 2006–2009. Fish and crayfish were the main prey, occurring in 86% and 27% of stomachs containing prey items, respectively. We identified 8 families and 11 genera of fish and 4 genera and 6 species of crayfish in the diet of River Otters. The most frequently consumed family of fish by occurrence was Centrarchidae (36%), followed by Catostomidae (11%), Cyprinidae (11%), and Clupeidae (7%). Centrarchidae were also found at the greatest volume (53%) of any family of fish, followed by Catostomidae (14%), Clupeidae (12%), and Cyprinidae (12%). Of the centrarchids, Group A fish (Lepomis, Ambloplites, and Pomoxis spp.; 28%) occurred at a higher percent in the diet of River Otters than Group B fish (Micropterus spp.; 5%). River Otter diets did not vary between males (n = 68) and females (n = 58), adults (n = 46) and juveniles (n = 80), or those from the western (n = 64) and eastern (n = 62) regions of the state.

We studied the distribution and ecology of male and female Myotis lucifugus (Little Brown Bats) and M. septentrionalis (Northern Long-eared Bats) on Newfoundland, where conditions (e.g., resource availability, abiotic conditions) were expected to be less favorable than in areas where most studies of conspecifics have occurred. We found that both species were patchily distributed and that Northern Long-eared Bats were more widely distributed across the island than previously documented. We located and characterized 36 roost trees from 14 female (6 lactating and 8 non-lactating) Northern Long-eared bats and found that, relative to conspecific populations on mainland North America, female Northern Long-eared Bats on the northern peninsula of Newfoundland roosted in shorter trees with smaller diameters. We also found that roosts used by lactating Northern Long-eared females were in cavities of large-diameter trees that maintained more stable microclimates compared to roosts used by non-lactating females.

The mesopelagic fish fauna in the Slope Sea off the Canadian continental shelf from 50° to 64°W is documented based on 10 surveys conducted in 1984–89. Species composition and relative species abundance by water mass (Labrador Slope Water [LSW], Warm Slope Water [WSW], and Gulf Stream), and their variation with season and fishing depth, are described. The most abundant species in collections was Ceratoscopelus maderensis, and this species dominated in WSW samples, but Benthosema glaciale was the predominant species in LSW samples. Gulf Stream samples were few and represented boundary conditions. Those species that were common in catches showed a seasonal variation in catch rate. Species composition varied with depth fished, deeper tows containing species, such as Cyclothone spp., that did not migrate to surface layers at night. The collections were comprised of at least 250 species. Although many of them have been reported from adjacent areas to the southwest, 35% of these species are new records for the sampled area, and 19 species are new records for the Slope Sea. Although a species accumulation curve indicates that more species would have been captured with additional sampling, it is likely that all species that occur regularly in the study area are represented in the species list.

Elemental concentrations and stable (δ ¹⁸O, δ¹³C) isotopic ratios in otoliths of young-of-the year (YOY) Tautoga onitis (Tautog) captured in nurseries in Rhode Island, Connecticut, New Jersey, and Virginia were determined using otolith micro-chemistry. Multi-chemical signatures differed significantly among the distinct nurseries among regions (MANOVA: P < 0.001) and between years (MANOVA: P < 0.001). Classification accuracy for Tautog nurseries among regions ranged from 92% to 96% for each of the two years. Since accurate classification of juvenile Tautog to their nursery sites was achieved, otolith chemistry can potentially be used as a natural habitat tag in assigning adult Tautog to their respective estuarine nurseries, but it is important to consider that the chemical signals may change annually.

Umbra pygmaea DeKay (Eastern Mudminnow) is one of four species of Umbridae in North America. There is little published life-history information on the species within its native range, particularly on age, growth, and reproduction. This study focuses on these aspects of the life history of this fish at the Great Swamp National Wildlife Refuge in Morris County, NJ. A total of 336 fish of seven species was collected from June 1978 through May 1979, with the Eastern Mudminnow comprising 74% of the total. The average annual growth increment in total length for the Eastern Mudminnow was 15.3 ∓ 2.06 mm, with age-1 fish averaging 40 mm total length and age-5 fish, the oldest collected, averaging 107 mm total length. The length-weight relationship was log₁₀W = -5.291 3.182 log₁₀TL mm for males and log₁₀W = -4.999 3.032 log₁₀TL mm for females. We observed no statistically significant sexually dimorphic differences in length-weight relationships in this population. The ratio of females to males increased from a low of 0.6 (predominance of male fish) at age-1 to a high of 4.6 (predominance of females) at age-5. Annual mortality for age 2–5 fish ranged from 40–76% with a mean of 59 ∓ 13%. Age-specific fecundity estimates ranged from 250 eggs/female at age-1 to 2168 eggs/female at age-5. The relationship of number of mature ova to age was best described by the exponential function y = 149.29e^0.5287x, where y = age-specific fecundity and x = age in years. Ova ranged from 0.1–0.2 mm in diameter in June and July and averaged 1.41 ∓ 0.1 mm (range = 1.29–1.62 mm) in early February prior to spawning. Peak spawning occurred in mid-April at temperatures of 9–12 °C, and all females were spent by late April (13–15 °C).

Amphibians and other herpetofauna may be useful in assessing the biological integrity of small streams, so determining which sampling technique maximizes encounters is important. Area-constrained surveys (ACS), used by the Maryland Biological Stream Survey, were tested against cover-board surveys, drift fences with pitfall and funnel traps, quadrat leaf-litter searches, leaf-litter bags, and electrofishing. Twenty sites within the coastal plain region of Maryland, west of the Chesapeake Bay, were sampled with each technique once a month from June 2006 through August 2006. Overall, ACS and electrofishing yielded significantly more taxa and total individuals than cover-board surveys, quadrat searches, and leaf-litter bags; drift fence captures were moderate between ACS and electrofishing and the other methods. Electrofishing and ACS collected both more taxa and more individuals more reliably through time than the other techniques used; therefore, efforts to use herpetofauna to monitor the health of small streams will benefit from incorporating these methods into a sampling protocol.

The exotic amphipod Echinogammarus ischnus, first reported in North America from western Lake Erie in 1995, was recorded in Oneida Lake, NY in 2001. Some North American studies have suggested that E. ischnus was replacing native amphipods, but other studies found no evidence for this. We sampled amphipods at six depths (<0.2, 0.6, 1.2, 1.8, 3.0, and >3.8 m) along six transects in Oneida Lake to quantify variation in densities of amphipod species as a function of depth, substrate (cobble with Dreissena and with or without macroalgae, sand with or without Dreissena, and macroalgae or submersed vascular plants) and density of Dreissena, and compared the present amphipod density to the historical record. Four species of amphipods, Gammarus fasciatus, Hyalella azteca, E. ischnus, and Crangonyx sp., were collected from Oneida Lake. Gammarus fasciatus was 9 to 90 times more abundant (mean = 0.09 individuals/cm²) than other amphipod species and was collected on all substrates and at all depths, as was H. azteca. Statistical comparisons were made with non-parametric tests between mean ranks of density of amphipods and Dreissena and the other variables. Mean ranks of density of G. fasciatus were correlated with depth (Spearman rank = 0.28, P < 0.0001), but mean ranks of density of H. azteca were not, and neither species was correlated with mean ranks of density of Dreissena. Mean ranks of density of G. fasciatus were greater on sand with or without macroalgae or submersed vascular plants (SVP) or Dreissena than on cobble with macroalgae and Dreissena (H = 28.2, P < 0.0001). Mean ranks of density of H. azteca were greater on sand with SVP, with or without Dreissena, than on sand with Dreissena and without SVP (H = 21.8, P = 0.0013). Echinogammarus ischnus was collected only in water less than 1.8 m depth and always with Dreissena. Mean ranks of density of E. ischnus were correlated with depth (Spearman rank = -0.29, P < 0.0001) and with Dreissena mean ranks of density (Spearman rank = 0.14, P = 0.01). Mean ranks of density of E. ischnus was greater on cobble with Dreissena than on sand with Dreissena regardless of the presence or absence of macroalgae or SVP (H = 35.4, P < 0.0001). Although E. ischnus is established in the near-shore zone of Oneida Lake, we found no evidence that it will replace the native amphipods G. fasciatus and H. azteca.

To address the question of how succession in protected habitats might be managed to favor rare understory plants in the Northeast, this study examined whether reducing shade might have negative impacts via increased herbivory or reduced pollination. We studied marginal populations of Trollius laxus Salisbury (Spreading Globeflower), a rare herbaceous plant of calcareous wetlands, making observations of natural variation in one population, and experimentally cutting back herbaceous neighboring plants in another. In a Trollius population under a mixed canopy, we quantified natural light levels at each plant and tested for correlations with measures of reproduction and herbivory. Flowering and fruit production were positively correlated with light level in one of the two years measured, while herbivore damage and plant growth were uncorrelated with light level. In another study population, where the woody canopy had been removed previously, experimental clipping of herbaceous neighbors did not increase herbivore damage to T. laxus, nor did it decrease flowering or fruit production. Also, the few potential pollinators observed were all small insects unlikely to be negatively affected by increased light. Our results suggest that management to reduce shade in these marginal T. laxus populations is unlikely to have a negative impact on these rare plants via their herbivores and pollinators.

A parsimony algorithm was used to evaluate the distribution and co-occurrence of 46 vascular salt marsh-associated species in 20 coastal salt marshes from Biscayne Bay National Park, FL, to Sable Island Marine Protected Sanctuary, NS, Canada. The method considers each salt marsh as if it were a taxon, and the presence or absence of a particular vascular plant species as a “character state” of that taxon. Using this information, a 20 × 46 data matrix was created and examined by multivariate ordination techniques and by parsimony analysis using the program WinClada running over NONA. A hierarchical clustering showed that the salt marsh sites on the eastern seaboard of North America formed two main clusters, one including all of the Florida sites and South Carolina, and the second including all of the more northern sites: North Carolina, Virginia, New Jersey, New York, and Sable Island, NS, Canada. Within the large southern cluster, we find two major sub-clusters separating the Florida marshes from those of South Carolina. Likewise, within the large northern cluster, we find two major sub-clusters separating North Carolina and Virginia from the other northern marshes. An essentially similar pattern of site grouping was also observed using the ordination technique of non-metric multidimensional scaling, in which the southern marshes all aligned to the left of the origin, while the more northern marshes align to its right. Parsimony analysis yielded twelve equally parsimonious trees from which a strict consensus tree was constructed. The topology of the consensus tree clearly shows two major clades, a southern one and a northern one, with the division occurring between South and North Carolina. The main southern clade is supported by the presence of Sporobolus virginicus (Seashore Dropseed), while the main northern clade is supported by the presence of Ruppia maritima (Widgeongrass). Spartina alterniflora (Smooth or Atlantic Cordgrass), which we take as the single species that defines the salt marsh on the eastern coast of North America, was present in all of the sampled sites except Biscayne Bay National Park, FL, a mangrove swamp.

Allelopathy is one explanation for non-native plant invasion, but native plants also can be allelopathic. We tested the allelopathic potentials of the non-native, invasive grass Microstegium vimineum (Japanese Stilt-grass) and the native herb Ageratina altissima (White Snakeroot), which both can dominate the herb layer in central New Jersey forests. Aqueous extracts from roots and shoots of both species negatively affected the speed of germination and the percent germination of Lettuce and Radish seeds in Petri dishes, and White Snakeroot shoot extract had the strongest effect. In a factorial experiment in pots of forest soil that combined extract treatments with activated carbon addition (to manipulate allelochemicals) and soil sterilization (to investigate indirect allelopathic effects via the soil microflora), Lettuce and Radish seedling establishment was reduced by extracts, especially from the native White Snakeroot. However, growth of surviving seedlings was unaffected by the extracts or their interactions with carbon or soil sterilization. These results show that a native species had stronger allelopathic potential than an aggressive, non-native invader from the same forest and that allelopathy was effective on the earliest developmental stages of the target plant species. In addition, activated carbon and sterilization interacted to directly influence plant growth. Growth was greater in sterilized than unsterilized soils, but only when carbon was added, suggesting caution in using these techniques in allelopathy studies.

We are reporting on established populations and sightings of species in the genus Amynthas in Vermont, from Quechee (43°38′N) central-eastern Vermont to Alburgh (44°58′N) on the northwest border to Canada. To our knowledge, these are the first sightings of Amynthas spp. reported for Vermont. Invasive Asian earthworms of the genus Amynthas were found at three of twelve forested locations surveyed for invasive European earthworms. In addition, Amynthas was found in a number of horticultural settings. We evaluated soils and climate information for forested sites with Amynthas in Vermont and compared climate with the original range and more southern US sites. Our findings suggest that Amynthas may expand its range even further north than Vermont and that the freeze-free period required for maturation is approximately 90 days.

Bergmann's Rule notes a correlation between animal size reduction and geographical temperature increase in three dimensions. This study examines bird size change in the context of temperature change in a fourth dimension: time. The body size of six passerine bird species found year-round in Connecticut was measured using museum specimens collected between 1874 and 2009, during which time mean temperature in Connecticut increased by 0.94 °C (SD = 0.71). Mean wing length significantly decreased from a pre-1955 period (1874–1952) to a post-1955 period (1958–2010) for all species combined (P < 0.0025) and for three of the six species (P < 0.025), suggesting that some Connecticut passerines exhibit an evolved size decrease since 1874. This study joins a growing body of research suggesting a causal relationship between climate change and animal morphological change, and it demonstrates the importance of museum specimens in documenting such global trends.

Male parental care can significantly affect fledging success and, therefore, is a strong target of both natural and sexual selection. However, for songbird species that exhibit extra-pair paternity, males may reduce parental care based on how much paternity they have lost in a brood. We studied Passerculus sandwichensis (Savannah Sparrow) male parental care relative to the proportion of extra-pair young in the nest, to see if males adjusted care in response to increasing loss of paternity. Males brought less food (mass) with increasing rates of extra-pair paternity, although male provisioning did not influence fledging success. These results contrast with a previously published study of an island population of this species, where males provided more parental care with increased loss of paternity. We hypothesize that high rates of annual survival in this mainland population, where males have a greater potential for reproduction in future years, may explain this difference in behavior.

The burying beetle Nicrophorus tomentosus (Silphidae) (Tomentose Burying Beetle) achieves an instant color change from a strikingly black and orange animal to a largely yellow one. This transformation achieves a mimicry of several species of bumble-bees when they are in flight, and it is accomplished by twisting the elytra to expose their yellow undersides while simultaneously hiding the bright orange and black upper sides. The overall effect is an apparent combination of both Muellerian and Batesian mimicry of bumblebees.

Sorex maritimensis (Maritime Shrew) is endemic to New Brunswick and Nova Scotia. We suggest that post-glacial dispersal northward by this species from a coastal plain refugium located in the mid-Atlantic, rather than dispersal from a refugium off Nova Scotia as previously proposed, is more parsimonious with current understanding of the glacial history of the region. A range extension into northeastern New Brunswick shows that the species is distributed north—south in New Brunswick and suggests that wetlands in heavily forested regions meet the ecological requirements of the Maritime Shrew. Such wetlands may provide avenues for dispersal and ensure connectivity among populations. Habitat descriptions for the Maritime Shrew indicate a wetland-associated species adaptable enough to utilize disturbance-dominated and anthropogenic wetlands. Further investigations of the biology of the Maritime Shrew are required to inform future habitat and wetland protection policies that should consider the requirements of this poorly known Canadian mammal.