The influence of Castor canadensis (North American Beaver) impoundments on the loss of nitrate (NO₃^-) from stream water was monitored for 14 months at four sites in Homer Gulf Creek in central New York State. A relatively high NO₃^- concentration of 1.56 (0.14) mg N/L (mean (SEM)) at the upstream site was reduced by a daily average of 35.5% as the water passed through the beaver ponds. There was a significant difference (P < 0.001) in the mean values among the four sites, and significant differences were measured between the upstream site and each of the three downstream sites. The reduction in NO₃^- within the upstream beaver pond was significantly (P = 0.005) greater during the warmer months (April–September) of the study vs. the October–March period, suggesting biological processes were responsible. Stream water NO₃^- may have been transformed through biological processes, including the microbial process of denitrification, enhanced in the beaver ponds as a result of anoxic sediments, sufficient supplies of labile organic matter, and increased water residence time.

Salvelinus fontinalis (Brook Trout) are simultaneously the subject of eradication efforts in the western US and restoration efforts in the East. Thus, knowledge of their habitat requirements are important to management as well as ecological understanding of the species. Previous studies have evaluated habitat use and movement of established, resident Brook Trout, but none had looked at how transplanted Brook Trout respond in novel environments, nor has habitat selection been evaluated under different flow regimes that may detect differential use of primary habitat. We implanted wild Brook Trout with radio tags and tracked their movement for approximately 30 days during late spring 2002 and early spring 2003 in a central Appalachian stream. The hypotheses tested were: (1) there is no difference between habitat used by novel Brook Trout and available habitat, and (2) stream discharge levels have no effect on Brook Trout habitat selection. The daily tracking of fish in this study also permitted us to quantify fish movement. Brook Trout showed a preference for pool habitats—using them in greater proportion than availability—as well as a preference for large woody debris as cover. Overall, we found stream discharge did not affect habitat use. However, under low discharge levels, a negative relationship between discharge and pool use was detected, suggesting restriction to pool habitats under low flows. Home ranges of Brook Trout derived from radio telemetry averaged 450 m—similar to values obtained in other Appalachian studies employing mark-and-recapture methods. A comparison of our results with those of other studies suggests that Brook Trout released into novel environments move and select habitat similar to fish that have local knowledge of the environment.

The warm water outflow at a power station in Northport, NY aggregates Morone saxatilis (Striped Bass) in winter, which creates unnatural angling opportunities. Substantially more Striped Bass were available to anglers in the winter of 1995–1996 than in the winter of 1996–1997. Although Striped Bass were observed within and around the heated effluent of the plume, tracking using ultrasonic transmitters indicated they were not “trapped” in the area by the colder water surrounding the discharge. However, there also was little evidence of a natural forage base. Tag returns from marked Striped Bass over subsequent years suggest that they displayed similar movement patterns to Striped Bass found in Long Island waters during other seasons. Differences in availability of Striped Bass among years may reflect seasonal changes in temperature, cohort abundance, and other factors.

The freshwater mussel (Unionidae: Bivalvia) communities of the French Creek watershed are nationally recognized for their importance to biodiversity. The goal of this research was to gather more information on the distribution and densities of these species throughout the river. This study utilized two-phase sampling with timed searches to characterize mussel species richness in a large number of sites and to calculate catch-per-unit-effort values. The results of the timed search were used to select a subset of sites for quantitative mussel surveys to estimate density and abundance. Starting in New York, the main stem of French Creek was divided into 5.6-km lengths, and one site was randomly chosen within each of those lengths, favoring habitat (large riffle/runs) for rare species and high species diversity. Snorkelers collected as many unionid individuals as possible, with a target search rate of 0.5 m² min^-1. Thirty-two main-stem sites were surveyed with timed searches. Mean species richness was 11.8 (SE = 0.94), and mean CPUE was 59.5 mussels per person-hour (SE = 9.32). Quantitative sampling was performed at ten sites using a double sampling design. Mean density estimates ranged from 0 to 27.98 m^-2. Abundance estimates range from 0 to 69,848 live mussels per site. For the main stem, we calculated regression models to estimate densities and abundances at qualitatively sampled sites based on the CPUE at quantitatively sampled sites. Extrapolation yields approximately 22 million mussels in the 2.04 million m² of large riffle-run habitat in the main stem of French Creek.

We develop a concept of suitable habitat for Glyptemys (Clemmys) muhlenbergii (Bog Turtle) on the Lake Ontario Coastal Plain of central and western New York State and compare it to habitat for this species in other parts of its distribution. At the outset of our studies in 1987, only a single Bog Turtle population was known to survive on the Lake Ontario Plain. We located and visited nine of the 10 historically recorded Bog Turtle sites in northern, central and western New York and completed a survey of 84 selected wetlands in Oswego County, at the eastern end of the Lake Plain. In the course of the study, we confirmed the presence of the Bog Turtle at a site where it was last documented in 1916 and discovered populations at three previously undocumented sites, one of which is now the northernmost recorded site for the species. Bog Turtle habitat on the Lake Ontario Coastal Plain is open-canopy, sedge-dominated medium to rich fens contained within larger wetlands that often include an open pond and extensive Acer rubrum (Red Maple) or Red Maple-Larix laricina (Tamarack) swamp. We discuss events that may have led to the current distribution of Bog Turtle populations in central and northern New York and in western Pennsylvania and implications of this distribution pattern for the conservation of the species.

Northern temperate forests play an important role in the global carbon (C) cycle. Individual stands can differ in C content and storage, based on characteristics such as vegetation type, site history, and soil properties. These site differences may cause stands to vary in their response to extreme weather events such as droughts. We examined ecosystem C pools, soil respiration, and litterfall in four hardwood stands with widely varying soil drainage in Rhode Island. Total ecosystem C increased as soils became more poorly drained, ranging from 181 Mg C ha-¹ in the excessively drained Entisol to 547 Mg C ha-¹ in the very poorly drained Histosol. The proportion of ecosystem C contained in the soil was much higher in the poorly drained soils, and ranged from 57% in the excessively drained Entisol to 91% in the poorly drained Histosol. While total ecosystem C stocks varied by a factor of three, rates of litterfall and soil respiration were similar among sites. Soil carbon content was highest in the very poorly drained site, and respiration was lowest from this site. During the summer drought of 1999, all soils except the Histosol had lower respiration rates than predicted from temperature alone. Rain events that ended the drought produced a pulse of soil respiration in all mineral soils, stimulating soil C flux more than expected from temperature alone. The effect of drought and rewetting on soil respiration varied by site, suggesting that the response to climate variability will depend upon soil drainage to some extent. Soil respiration rates were most variable in dry conditions, and current and antecedent soil moisture conditions played an important role during those times. In general, soil respiration was much more variable over time than across sites, even among these sites with very different total soil C content, indicating that climate—mainly temperature—is the main determinant of soil CO₂ release even across soils with widely varying drainage.

Solitary nest-provisioning wasps and bees in North America include species that naturally construct nests within existing cavities, such as hollow plant stems or tunnels left by wood-boring insects. The materials used to construct brood cells within nest cavities and the types of food provisions provided to offspring vary considerably among species. Over five summers (2001–2002, 2005–2007), we used trap nests to survey the cavity-nesting wasp and bee assemblage within the Montezuma Wetlands Complex in central New York State. Over 350 trap nests were occupied by 6 species of apoid wasps (Sphecidae, Crabronidae; 34% of nests), 7 vespid wasps (Vespidae: Eumeninae; 39%), 2 spider wasps (Pompilidae; 3%), and 12 bees (Megachilidae, Colletidae; 26%), as well as brood parasites and parasitoids of the nest provisioners. The most common nest-provisioning wasp was Trypoxylon lactitarse, followed by Ancistrocerus antilope, Isodontia mexicana, Symmorphus canadensis, Symmorphus cristatus, and Euodynerus foraminatus. The only two bee species with comparable incidences were Hylaeus annulatus and Heriades carinatus. Natural enemies emerging from nests included at least 17 species from 10 families, the most common of which were brood-parasitic cuckoo wasps (7 species of Chrysididae; 39 nests) and flies (Sarcophagidae; 11 nests). We also report brood sex ratios of the seven most abundant species, finding them to be either male-biased (A. antilope, T. lactitarse), female-biased (E. foraminatus), or not significantly different from unity. We compare our survey results to others done in north-central and eastern North America.

“Pimple” dunes are small, rounded coastal dunes that form along major dune ridges of the barrier islands along the Eastern Shore of Virginia. Although most pimple dunes are small structures ranging between 10 and 20 m in diameter, they have distinct plant assemblages that replicate the upland ecotones of their barrier islands. We examined the relationship between microenvironment, edaphic factors, and plant assemblage structure on pimple dunes. Water availability was an obvious major ecological driver, but we also tested other environmental factors that may correlate with plant assemblage structure. We found distinct assemblage types that segregated themselves by habitat type: marsh, shrub thicket, and dry summit. Freshwater availability was important in delineating vegetation differences, both among transects and among species. However, soil nutrients, such as ammonium, potassium, magnesium, and boron, were also spatially correlated with plant assemblage structure. We hypothesize that interactions between water and other environmental factors (e.g., the accumulation of nutrients in the marsh after they are leached from the dune summits) are important determinants of plant species distribution and abundance, and suggest that more attention be given to micronutrients in future phytosociological studies of barrier islands.

We evaluated thirteen years (1995–2007) of Charadrius melodus (Piping Plover) nesting activity at Jones Beach State Park (JBSP) to examine temporal trends in the number of pairs, productivity, total young produced per year, and nest initiation. The number of plover pairs has decreased over time at JBSP, while productivity (and total number of young produced per year) has increased. Productivity has increased more at JBSP compared to other areas in their range. In addition, nest initiation was significantly later in the nesting season in recent years. Increased productivity indicates that management efforts to increase this population parameter may have had a positive effect on nesting plovers. The decreased numbers of nesting pairs, however, suggests that management techniques to increase numbers of breeding pairs, such as nesting-habitat restoration, may also be necessary to increase local population size. In the absence of suitable nesting habitat for recruitment of locally fledged birds, JBSP may be functioning as a “source” for other regional breeding populations.

The distribution of Sylvilagus obscurus (Appalachian Cottontail) is disjunct and restricted to high-elevation refuges in the central and southern Appalachian Mountains. The purpose of this study was to determine survival and winter diet of this rabbit at its type locality, the Dolly Sods area of the Monongahela National Forest, WV. To estimate survival, 44 Appalachian Cottontail individuals were radio-tracked until death or loss of transmitter signal between October 1997 and June 2000. The Kaplan-Meier estimate was used to generate finite survival rates. To assess winter diet, stems browsed within a 1-m radius of winter radiolocations of 15 individuals in 1998–1999 and 1999–2000 were identified and counted. Species and groups of species browsed were compared to availability, determined by counting the number of woody stems within a 1-m radius of the same radiolocations. Overall daily survival rate was 0.9934, finite monthly (28-day) survival rate was 0.8309, and finite yearly survival rate was 0.0894. No differences in survival were found between sexes or age groups. The first leaf-off season had lower daily survival rates than those of the subsequent leaf-on and leaf-off seasons. Gaultheria procumbens (Eastern Teaberry), Vaccinium spp. (blueberries), Gaylussacia baccata (Black Huckleberry), and Photinia spp. (chokeberries) were preferred winter browse. Rhododendron spp. and the abundant Kalmia latifolia (Mountain Laurel) were consumed less than expected.