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At least 145 records · Page 8Linked to original sources

A Common Loon incubates rocks as surrogates for eggs

A nesting Gavia immer (Common Loon) was discovered incubating 2 rocks on a floating nest platform on the Quabbin reservoir in central Massachusetts for 43 days, well beyond the typical period of 28 days, before we moved in to investigate. The rocks were likely unearthed in the soil and vegetation used on the platform to create a more natural substrate for the nest. We suggest sifting through soil and vegetation to remove rocks before placing material on nest platforms.

Northeastern Naturalist

First records of Nocomis biguttatus (Hornyhead Chub) from West Virginia discovered in museum voucher specimens

Specimens of Nocomis biguttatus (Hornyhead Chub) from South Fork Hughes River (Little Kanawha River drainage, WV) were discovered in two museum lots at the North Carolina Museum of Natural Sciences. These accessions, collected in 1960 and 1966, represent an addition to the state fauna and are the first distribution records for this species from the Appalachian Plateau, WV

Northeastern Naturalist

Comparison of radio-telemetric home range analysis and acoustic detection for Little Brown Bat habitat evaluation

With dramatic declines of bat populations due to mortality caused by Pseudogymnoascus destructans (White-nose Syndrome), assessing habitat preferences of bats in the northeastern US is now critical to guide the development of regional conservation efforts. In the summer of 2012, we conducted fixed-station simultaneous telemetry to determine nocturnal spatial use and fixed-kernel home-range estimates of available habitat of a Myotis lucifugus (Le Conte) (Little Brown Bat) maternity colony in an artificial bat house. In summers of 2011 and 2012, we also deployed a 52-ha grid of 4 × 4 Anabat acoustic detectors over five 6–8-day sampling periods in various riparian and non-riparian environments in close proximity to the same bat house. The mean telemetry home range of 143 ha for bats ( n = 7) completely overlapped the acoustic grid. Rankings of habitats from telemetry data for these 7 bats and 5 additional bats not included in home-range calculations but added for habitat-use measures ( n = 13) revealed a higher proportional use of forested riparian habitats than other types at the landscape scale. Pair-wise comparisons of habitats indicated that bats were found significantly closer to forested riparian habitats and forests than to open water, developed areas, fields, shrublands, or wetland habitats at the landscape scale. Acoustic sampling showed that naïve occupancy was 0.8 and 0.6 and mean nightly detection probabilities were 0.23 and 0.08 at riparian and non-riparian sites, respectively. Our findings suggest that Little Brown Bats select forested riparian and forested habitats for foraging at the landscape scale but may be most easily detected acoustically at riparian sites when a simple occupancy determination for an area is required.

Northeastern Naturalist

Raccoon ( Procyon lotor ) diurnal den use within an intensively managed forest in central West Virginia

Intensive forest management may influence the availability of suitable den sites for large den-seeking species, such as Procyon lotor (Raccoon). As part of a Raccoon ecology study on an industrial forest in the Allegheny Mountains of central West Virginia, we radio-tracked 32 Raccoons to 175 diurnal den sites to determine relative use of dens that included cavity trees, rock dens, log piles, slash piles, and exposed limbs. Patterns of den use significantly differed between sexes and among seasons. Overall, we recorded 58 cavity dens in 12 tree species with 7 maternal dens found in 5 tree species. Raccoons selected larger-diameter den trees than available cavity trees and non-cavity trees. Because the abundance of suitable tree cavities is known to influence Raccoon densities and recruitment at fine spatial scales and female Raccoons in this study used tree cavities as maternal den sites, the continued harvest of large-diameter trees (i.e., those capable of developing den cavities) without replacement may impact Raccoon recruitment within intensively managed forests throughout the central Appalachians.

Northeastern Naturalist

Distribution of native mussel (unionidae) assemblages in coastal areas of Lake Erie, Lake St. Clair, and connecting channels, twenty-five years after a dreissenid invasion

Over the past 25 years, unionid mussels in the Laurentian Great Lakes of North America have been adversely impacted by invasive dreissenid mussels, which directly (e.g., by attachment to unionid shells) and indirectly (e.g., by competing for food) cause mortality. Despite the invasion, unionids have survived in several areas in the presence of dreissenid mussels. We investigated current spatial patterns in these native mussel refuges based on surveys for unionid mussels across 48 sampling locations (141 sites) in 2011 and 2012, and documented species abundance and diversity in coastal areas of lakes St. Clair and Erie. The highest-quality assemblages of native mussels (densities, richness, and diversity) appear to be concentrated in the St. Clair delta, where abundance continues to decline, as well as in in Thompson Bay of Presque Isle in Lake Erie and in just a few coastal wetlands and drowned river-mouths in the western basin of Lake Erie. The discovery of several new refuge areas suggests that unionids have a broader distribution within the region than previously thought.

Lake Erie, Lake St. Clair

Fish assemblages in the Upper Esopus Creek, NY: Current status, variability, and controlling factors

The Upper Esopus Creek receives water diversions from a neighboring basin through the Shandaken Tunnel (the portal) from the Schoharie Reservoir. Although the portal is closed during floods, mean flows and turbidity of portal waters are generally greater than in Esopus Creek above their confluence. These conditions could potentially affect local fish assemblages, yet such effects have not been assessed in this highly regulated stream. We studied water quality, hydrology, temperature, and fish assemblages at 18 sites in the Upper Esopus Creek during 2009–2011 to characterize the effects of the portal input on resident-fish assemblages and to document the status of the fishery resource. In general, fish-community richness increased by 2–3 species at mainstem sites near the portal, and median density and biomass of fish communities at sites downstream of the portal were significantly lower than they were at sites upstream of the portal. Median densities of Salmo trutta (Brown Trout) and all trout species were significantly lower than at mainstem sites downstream from the portal—25.1 fish/0.1 ha and 148.9 fish/0.1 ha, respectively—than at mainstem sites upstream from the portal—68.8 fish/0.1 ha and 357.7 fish/0.1 ha, respectively—yet median biomass for Brown Trout and all trout did not differ between sites from both reaches. The median density of young-of-year Brown Trout at downstream sites (9.3 fish/0.1 ha) was significantly lower than at upstream sites (33.9 fish/0.1 ha). Waters from the portal appeared to adversely affect the density and biomass of young-of-year Brown Trout, but lower temperatures and increased flows also improved habitat quality for mature trout at downstream sites during summer. These findings, and those from companion studies, indicate that moderately turbid waters from the portal had few if any adverse impacts on trout populations and overall fish communities in the Upper Esopus Creek during this study.

New York

Effects of population reduction on white-tailed deer home-range dynamics

Management strategies designed to reduce the negative impacts of overabundant Odocoileus virginianus (White-tailed Deer) populations on forest regeneration may be influenced by changes in both population density and timber harvest. However, there is conflicting evidence as to how such changes in per capita resource availability influence home-range patterns. We compared home-range patterns of 33 female White-tailed Deer from a low-density population at a site with abundant browse to patterns of a sample of >100 females prior to a 75% reduction in population density and a doubling in timber harvest area. Home-range and core-area sizes were approximately 3 times larger than were found prior to population decline and timber harvest increase, consistent with predictions related to intraspecific competition. We also observed greater site fidelity than previously exhibited, although this may be an artifact of increased home-range sizes. Our results support previous research suggesting that White-tailed Deer home-range size is inversely related to population density and is driven, in part, by intraspecific competition for resources. Relationships among population density, resource availability, and home-range patterns among female White-tailed Deer appear to be complex and context specific.

West Virginia

Loss of eelgrass in Casco Bay, Maine, linked to Green Crab disturbance

Over half of the Zostera marina (Eelgrass) cover disappeared from Casco Bay, ME, largely between 2012 and 2013. Eelgrass decline coincided with a population explosion of the invasive crab Carcinus maenas (European Green Crab). Green Crabs have been found to damage Eelgrass in Atlantic Canada through foraging activity, but destruction of established beds had not been documented in Maine. My objective was to determine whether loss of Eelgrass from Casco Bay was related to Green Crab disturbance. In September 2013, I transplanted Eelgrass shoots inside and outside of replicate Green Crab exclosures in a formerly vegetated area of upper Casco Bay. Following 26 d, mean survival of Eelgrass inside the exclosures was 82% and outside the exclosures was 24%. The mean plastochrone interval (time between formation of 2 successive leaves) of undamaged shoots was the same inside and outside the exclosures, and was comparable to published values from healthy Eelgrass beds in New England. Results implicate Green Crab bioturbation as a leading cause of Eelgrass loss from this system.

Maine

Evaluation of a formula that categorizes female gray wolf breeding status by nipple size

The proportion by age class of wild Canis lupus (Gray Wolf) females that reproduce in any given year remains unclear; thus, we evaluated the applicability to our long-term (1972–2013) data set of the Mech et al. ( 1993 ) formula that categorizes female Gray Wolf breeding status by nipple size and time of year. We used the formula to classify Gray Wolves from 68 capture events into 4 categories (yearling, adult non-breeder, former breeder, current breeder). To address issues with small sample size and variance, we created an ambiguity index to allow some Gray Wolves to be classed into 2 categories. We classified 20 nipple measurements ambiguously: 16 current or former breeder, 3 former or adult non-breeder, and 1 yearling or adult non-breeder. The formula unambiguously classified 48 (71%) of the nipple measurements; based on supplemental field evidence, at least 5 (10%) of these were incorrect. When used in conjunction with an ambiguity index we developed and with corrections made for classifications involving very large nipples, and supplemented with available field evidence, the Mech et al. ( 1993 ) formula provided reasonably reliable classification of breeding status in wild female Gray Wolves.

Minnesota

Reintroduction of Lake Sturgeon ( Acipenser fulvescens ) into the St. Regis River, NY: Post-release assessment of habitat use and growth

One of the depleted endemic fish species of the Great Lakes, Acipenser fulvescens (Lake Sturgeon), has been the target of extensive conservation efforts. One strategy is reintroduction into historically productive waters. The St. Regis River, NY, represents one such adaptive-management effort, with shared management between New York and the St. Regis Mohawk Tribe. Between 1998 and 2004, a total of 4977 young-of-year Lake Sturgeon were released. Adaptive management requires intermediate progress metrics. During 2004 and 2005, we measured growth, habitat use, and survivorship metrics of the released fish. We captured a total of 95 individuals of all stocked ages. Year-class minimal-survival rates ranged from 0.19–2.1%. The size-at-age and length/biomass relationships were comparable to those reported for juveniles in other Great Lakes waters. These intermediate assessment metrics can provide feedback to resource managers who make restoration-program decisions on a much shorter time-scale than the time-frame in which the ultimate goal of a self-sustaining population can be attained.

New York

Seasonal variation in habitat use of juvenile Steelhead in a tributary of Lake Ontario

We examined seasonal-habitat use by subyearling and yearling Oncorhynchus mykiss (Rainbow Trout or Steelhead) in Trout Brook, a tributary of the Salmon River, NY. We determined daytime fish-habitat use and available habitat during August and October of the same year and observed differences in habitat selection among year classes. Water depth and cover played the greatest role in Steelhead habitat use. During summer and autumn, we found yearling Steelhead in areas with deeper water and more cover than where we observed subyearling Steelhead. Both year classes sought out areas with abundant cover during both seasons; this habitat was limited within the stream reach. Subyearling Steelhead were associated with more cover during autumn, even though available cover within the stream reach was greater during summer. Principal component analysis showed that variation in seasonal-habitat use was most pronounced for subyearling Steelhead and that yearling Steelhead were more selective in their habitat use than subyearling Steelhead. The results of this study contribute to a greater understanding of how this popular sportfish is adapting to a new environment and the factors that may limit juvenile Steelhead survival. Our findings provide valuable new insights into the seasonal-habitat requirements of subyearling and yearling Steelhead that can be used by fisheries managers to enhance and protect the species throughout the Great Lakes region.

New York

Changes in rates of capture and demographics of Myotis septentrionalis (Northern Long-eared Bat) in Western Virginia before and after onset of white-nose syndrome

Documenting the impacts of white-nose syndrome (WNS) on demographic patterns, such as annual survivorship and recruitment, is important to understanding the extirpation or possible stabilization and recovery of species over time. To document demographic impacts of WNS on Myotis septentrionalis (Northern Long-eared Bat), we mistnetted at sites in western Virginia where Northern Long-eared Bats were captured in summer before (1990–2009) and after (2011–2013) the onset of WNS. Our mean capture rates per hour, adjusted for area of net and sampling duration, declined significantly from 0.102 bats/ m 2 /h before WNS to 0.005 bats/m 2 /h (-95.1%) by 2013. We noted a time lag in the rate of decline between published data based on bats captured during the swarming season and our summer mist-netting captures from the same geographic area. Although proportions of pregnant or lactating females did not vary statistically in samples obtained before and after the onset of WNS, the proportion of juvenile bats declined significantly (-76.7%), indicating that the viability of Northern Long-eared Bats in western Virginia is tenuous.

Virginia

Evidence for range contraction of snowshoe hare in Pennsylvania

In Pennsylvania, Lepus americanus (Snowshoe Hare) is near the southern limits of its range and at risk of range contraction because of loss of early-successional forest and impacts of climate change. We used hunter-harvest data to investigate changes in the distribution of Snowshoe Hare in Pennsylvania (1983–2011), forest inventory and land-use data to assess changes in amount and distribution of early-successional forest (1988–2011), and occupancy modeling (2004) to identify habitat and climate variables that explain the current distribution of Snowshoe Hare. We determined presence of Snowshoe Hare based on visual sightings, observations of tracks, and DNA analysis of fecal pellets, and used repeated visits to sampling sites and occupancy models to estimate occupancy rates (Ψ). Hunter-harvest data indicated the range of Snowshoe Hare in Pennsylvania contracted towards northwestern and northeastern portions of the state. Based on occupancy modeling, Snowshoe Hare were most likely to occupy early-successional and mixed deciduous-coniferous forest types and areas with colder winter temperatures, which coincided with the distribution of hunter harvests. Among the 4 forest types, we estimated Ψ = 0.52-0.79 and Ψ = 0.10-0.32 where winter temperatures were coldest and warmest, respectively. Total forest loss was <1% during 1988-2011, and the loss of early-successional forest in the current and former range of Snowshoe Hares was similar as were mean patch size and a fragmentation metric of early-successional habitat. Thus, changes in forest characteristics did not explain the range contraction we observed. We used climate-model predictions and our occupancy model to predict that average occupancy probability across northern Pennsylvania may decline from 0.27 in 2004 to 0.10–0.18 by 2050–2059, depending on the climate model. The range of Snowshoe Hare in Pennsylvania has contracted to regions of Pennsylvania with the coldest winter temperatures and most persistent snowpack, and based on projected climate change, our results suggest further range contraction of Snowshoe Hare in Pennsylvania.

Pennsylvania

A comparison of three macroinvertebrate sampling devices for use in conducting rapid-assessment procedures of Delmarva Peninsula wetlands

Three types of macroinvertebrate collecting devices, Gerking box traps, D-shaped sweep nets, and activity traps, have commonly been used to sample macroinvertebrates when conducting rapid biological assessments of North American wetlands. We compared collections of macroinvertebrates identified to the family level made with these devices in 6 constructed and 2 natural wetlands on the Delmarva Peninsula of Maryland. We also assessed their potential efficacy in comparisons among wetlands using several proportional and richness attributes. Differences in median diversity among samples from the 3 devices were significant; the sweep-net samples had the greatest diversity and the activity-trap samples had the least diversity. Differences in median abundance were not significant between the Gerking box-trap samples and sweep-net samples, but median abundance among activity-trap samples was significantly lower than among samples of the other 2 devices. Within samples, the proportions of median diversity composed of major class and order groupings were similar among the 3 devices. However the proportions of median abundance composed of the major class and order groupings within activity-trap samples were not similar to those of the other 2 devices. There was a slight but significant increase in the total number of families captured when we combined activity-trap samples with Gerking box-trap samples or with sweep-net samples, and the per-sample median numbers of families of the combined activity-trap and sweep-net samples was significantly higher than that of the combined activity-trap and Gerking box-trap samples. We detected significant differences among wetlands for 4 macroinvertebrate attributes with the Gerking box-trap data, 6 attributes with sweep-net data, and 5 attributes with the activity-trap data. A small, but significant increase in the number of attributes showing differences among wetlands occurred when we combined activity-trap samples with those of the Gerking boxtrap or sweep net.

Delaware, Maryland

Who knew? First Myotis sodalis (Indiana Bat) maternity colony in the coastal plain of Virginia

We report the first confirmed Myotis sodalis (Indiana Bat) maternity colony in Virginia, discovered at Fort A.P. Hill Military Reservation in Caroline County along the Piedmont-Coastal Plain Fall Line. Acoustic surveys conducted in 2014 indicated likely presence of Indiana Bats on the installation. Subsequent focal mist-netting during May–June 2015 resulted in capture of 4 lactating females that we subsequently radio tracked to a maternity colony site containing at least 20 individuals. The core roosting-area was comprised of Pinus taeda (Loblolly Pine) snags with abundant exfoliating bark and high solar exposure. This forest patch was adjacent to a large emergentshrub wetland and within a larger matrix of mature, mid-Atlantic hardwood forests. The site where we found the colony location is 140 km east of the nearest known hibernaculum and is outside of the previously documented extent of this species' occurrence.

Virginia

Gray Wolf (Canis lupus) death by stick impalement

Although Canis lupus L. (Gray Wolf) individuals are sometimes impaled by sticks, we could find no documentation of natural impalement by sticks as a cause of death for wild Wolves. Here we report on a wild Gray Wolf from northeastern Minnesota that died due to stick puncture of its thorax and abdomen.

Minnesota

Microhabitat selection of the Virginia Northern Flying Squirrel (Glaucomys sabrinus fuscus Miller) in the central Appalachians

Glaucomys sabrinus fuscus (Virginia Northern Flying Squirrel; VNFS) is a rare Sciurid that occurrs in the Allegheny Mountains of eastern West Virginia and northwest Virginia. Previous work on this subspecies has confirmed close associations with Picea rubens (Red Spruce) at the landscape and stand levels in the region. However, ongoing Red Spruce restoration actions using canopy-gap creation to release single or small groups of trees requires a better understanding of within-stand habitat selection of VNFS to assess potential short- and medium-term impacts. To address these questions, we conducted a microhabitat study using radio-collared squirrels in montane conifer and mixed conifer—hardwood stands. We used points obtained from telemetry surveys and randomly generated points within each squirrel's home range to compare microhabitat variables for 13 individuals. We found that VNFS preferentially selected plots with conifer-dominant overstories and deep organic-soil horizons. VNFS avoided plots with dense Red Spruce regeneration in the understory in stands with hardwood-dominated overstories—the types of areas targeted for Red Spruce restoration. We also opportunistically searched for hypogeal fungi at telemetry points and found 3 species of Elaphomyces during our surveys. Our results indicate that microhabitat selection is associated with Red Spruce-dominant forests. Efforts to restore Red Spruce where hardwoods dominate in the central Appalachians may improve the connectivity and extent of habitat of VNFS.

West Virginia

Atypical feeding behavior of Long-tailed Ducks in the wake of a commercial fishing boat while clamming

A foraging group of Clangula hyemalis (Long-tailed Duck) was observed on 10 February 2010 diving behind a commercial boat that was clamming near Monomoy Island, Nantucket Sound, MA. We used a shotgun to collect 9 of the ducks, and our analyses of gizzard and gullet (esophagus and proventriculus) revealed 37 food items in the gizzard and 16 in the gullet. Mollusca were the dominant food in the gizzard (49%), whereas Crustacea were dominant in the gullet (57%). Crustacea were the second most important food in the gizzard (38%), whereas Mollusca were the second most important food in the gullet (31%). Relatively high volumes of the Amphipoda Caprella sp. (skeleton shrimp) and the Decopoda Crangon septemspinosa (Sand Shrimp) were recorded in the gullet and gizzard. Ensis directus (Atlantic Jackknife Clam) formed the greatest volume of Mollusca in the gizzard (15%) and in the gullet (15%). Long-tailed Ducks had fed on this Bivalvia and several other species of Mollusca that had no shell or broken shell when consumed. Many of the food organisms were apparently dislodged and some damaged by the clamming operation creating an opportunistic feeding strategy for the Long-tailed Ducks.

Massachusetts