Lynx rufus (Bobcat) is a wide-ranging and highly adaptable predator whose populations are increasing throughout much of its natural range including in the New England states, yet there are only limited empirical ecological studies there. How Bobcats are responding to the unique modern landscape of southern New England with its highly forested landscape coupled with high density of humans is unknown. This lack of spatial and population ecological information impedes evaluating recovery and management objectives and identifying necessary management actions. Our objectives were to better understand the spatial and population structure of Bobcats in Rhode Island. We specifically examined space use, resource selection, and population genetics. We trapped Bobcats across 5 field seasons from April 2015 to March 2019, totaling 2232 trap nights. We captured 8 Bobcats, equipped GPS collars to a subset (n = 3), and collected locations for 4 to 9 months. We used GPS locations to estimate annual and seasonal home-range size and individual-level seasonal resource selection within the home range for each individual. Further, we used tissue samples collected from trapped individuals and opportunistically collected roadkill (n = 30) to examine the population genetic structure and effective population size of Bobcats in the state. We found the mean winter and summer home-range sizes were 219.3 km² and 51.7 km², respectively. Bobcats selected for forested wetland habitats and were associated with areas closer to wetlands and young forests, according to resource-selection models. They also selected for areas with higher road densities, yet avoided developed areas. We found that Bobcats in Rhode Island are part of 1 genetic population and estimated their effective population size to be 82 individuals (95% CI: 44–329). Our study highlights the importance of examining a widely distributed species at a local scale in order to employ evidence-based management practices.

Consistently repeated daily habitat shifts by fish can expose or protect individuals from a variety of threats and influence nutrient transport between systems, yet logistical constraints make individual horizontal movement difficult to study on short time scales. As a result, diel movements by fish are often poorly documented. Suckers (Catostomidae) are a key group of fish that have been frequently examined with this in mind, as many species are large, long-lived, and comprise a large proportion of biotic biomass in many waters. Previous studies in rivers have shown that multiple sucker species exhibit complex, diel movement. We investigated the prevalence of short-term movement by the widely distributed Catostomus commersonii (White Sucker) in an interconnected, remote lake system within New York's Adirondack region using PIT telemetry. These 2 lakes were in a remote setting of New York's Adirondacks, and our tracking studies indicated a subset of the sucker population regularly traveled back and forth daily through a short, shallow channel. Direction of movement was strongly associated with time of day, and larger individuals were far more likely to engage in this repetitive behavior. Overall, these findings highlight the potential for extensive, yet generally unobserved, movement by White Suckers within connected lake systems.

Climate warming is likely to cause differential shifts in the phenology of pollinators and nectar sources. Detection of these shifts requires careful observation of emergence and peak populations of both the animals and plants involved. On salt marshes of Canada's Chaleur Bay, the potential for asynchronous appearance of the adults of the endangered butterfly Coenonympha nipisiquit (Maritime Ringlet) and its primary nectar sources has become a concern. We used citizen scientists and simple equipment to collect field observations of blooming of key nectar sources: Lysimachia maritima (= Glaux maritima) (Sea Milkwort), Limonium carolinianum (Sea Lavender, Carolina Sea Lavender, or American Thrift), and Solidago sempervirens (Seaside Goldenrod). These species have distinctly different flowering architectures that present varied challenges to observations of initiation of blooming and peak blossoming; therefore, our results have value to a diversity of environments. We show how techniques of remote sensing can be applied to analyze photographs collected by citizen scientists, thus providing records of peak blooming and eliminating observer bias. The success of photographic monitoring depends upon floral architecture and simple shading to prevent oversaturation of sunlight.

We used egg-mass counts to monitor populations of Lithobates sylvaticus (Wood Frog) and Ambystoma maculatum (Spotted Salamander) at 4 ponds located in central Vermont. We monitored numbers of egg-masses for 15 springs over the course of 20 years (2000–2020). Each year, the number of Wood Frog egg-masses at our breeding sites increased rapidly, over a period of close to 2 weeks. Spotted Salamanders deposited eggs beginning about a week later than the Wood Frogs, and the number of their egg-masses increased at our study sites over a period of up to 8 weeks. Consequently, when using egg-mass counts to determine presence/absence or to monitor populations, it is important to take the relative phenology of these 2 species into consideration.

The Virginia barrier islands lie along the seaward margin of the southern Delmarva Peninsula in the mid-Atlantic region of the United States, and collectively they comprise an internationally recognized biosphere reserve. Despite this recognition, no comprehensive checklist of mammals exists for the islands or the adjacent Delmarva Peninsula mainland. Herein we report on the species composition of terrestrial mammals of this region based on (1) a search of museum collections, (2) a compilation of literature sources and personal communications, and (3) our own extensive fieldwork (1975–2020). We documented 6 orders, 12 families, and 25 species of native terrestrial mammals. The islands are depauperate in comparison with the mainland, with several native species missing from the islands. We also documented 3 orders, 3 families, and 4 species of non-native mammals that are currently established on the islands. In addition, we herein present a historical overview of livestock species that were introduced to the islands, but (with 1 exception) no longer occur there. European settlement of the mainland and the islands began in the early 1600s; however, permanent human structures have been absent from most of the islands for the past 60+ years, leaving them undeveloped and in a natural state. These islands are undergoing rapid geological and ecological change under the pressure of accelerated sea-level rise associated with climate change. This checklist provides a foundation for future biogeogeographic studies of mammals in this region and serves as a baseline against which to measure future ecological and distributional changes.

Environmental DNA (eDNA) analysis has become a widespread conservation tool. One promising direction is to evaluate the impacts of anthropogenic disturbances on wildlife populations. In 2016, a ruptured pipeline caused 207,000 L of gasoline to spill into a tributary of the West Branch Susquehanna River in central Pennsylvania. This tributary is known to harbor one of Pennsylvania's most prolific populations of Cryptobranchus alleganiensis alleganiensis (Eastern Hellbender), a giant salamander of special conservation concern. To evaluate the impact of the gasoline spill on Hellbender populations, we conducted spatial eDNA analysis on 9 water samples collected along a 20-km stretch of the tributary in 2018. Spatial analysis identified a notably low eDNA concentration at the site immediately downstream of the spill site, likely a result of habitat destruction caused by the flood, gasoline spill, and subsequent construction of a new bridge and stream bank. We found relatively high eDNA concentrations at several sampled sites, suggesting the gasoline spill did not completely extirpate Hellbender populations from the tributary. Finally, we make recommendations on sampling regimes, including proactive sampling, to encourage eDNA-based assessments of the impacts of future spill events on wildlife populations.

As a result of surveying effort since 2015, I herein report 7 species of Zygaenoidea from Block Island, a small offshore island in southern New England with a history of intensive agricultural use. I quantify species phenology and local abundance, compare the island's fauna to those of nearby landmasses and the broader region, and discuss possible future colonization of Block Island by additional species as well as the likely factors behind the composition of the island's zygaenoid fauna.

Vireo gilvus (Warbling Vireo) is the smallest bird species in North America known to eject Molothrus ater (Brown-headed Cowbird) eggs from their nests. Populations eject parasitic eggs in central North America and the Great Lakes region but not in western North America. The geographic differences in behavior may reflect the range distributions of 2 subspecies. However, experimental studies of egg ejection in eastern populations are currently lacking. To address this gap, I experimentally parasitized 3 Warbling Vireo nests in Massachusetts using real and model cowbird eggs. At all 3 nests, Warbling Vireos ejected the parasitic egg. To my knowledge, this is the first documented account of parasitic egg ejection by Warbling Vireos east of the Great Lakes region.

Highway roadside verges (HRV) provide supplemental habitat for birds in intensive agricultural and suburban landscapes where the natural habitats are rapidly disappearing. The purpose of this study was to document the behavior of breeding bird species using the vegetation maintenance units (green shoulders, embankments, ditches, and banks) of HRV in 3 typical rural landscapes of southern Quebec, Canada. We observed the behavior of 722 individuals of 21 bird species. The most abundant ones (especially Sturnus vulgaris [European Starling] and Agelaius phoeniceus [Red-winged Blackbird]) foraged in the green shoulders, while others (such as Melospiza melodia [Song Sparrow], Spinus tristis [American Goldfinch], and Geothlypis trichas [Common Yellowthroat]) travelled or nested in the low vegetation in ditches and on the banks. Omnivorous species forage in the green shoulders and used the banks and ditches mainly for nesting-related behaviors, just like the few insectivorous species observed. The granivorous species were almost absent from studied HRV. Ground-foraging species used the shoulders to feed but nested in ditches and banks. Species foraging in low vegetation foraged mainly on the banks and used the ditches more for travelling. Reducing the mowing frequency of these 2 maintenance units would likely result in an increase in the vegetation cover and would thus provide additional nesting and foraging habitat for the species we recorded, 67% of which show a stable or declining population in North America.

The richness, abundance, and biomass of phytophagous arthropods like lepidopteran larvae is highly uneven among sympatric tree taxa. Optimal foraging theory predicts that predation pressure will be greatest on foraging substrates that support the highest abundance and/or diversity of prey, thus offering the greatest reward and maximizing fitness. Predation pressure can also vary with the nutritional or energetic needs of predators across the annual cycle. For insectivorous birds, prioritizing foraging effort in trees that support the most insect prey can benefit individuals by improving their foraging efficiency, condition, and ultimately fitness. However, we lack an understanding of how trees vary in their support of bird foraging activity across seasons and among plant taxa. We used plasticine caterpillar models to measure avian predation rates on 9 native North American tree species that vary in caterpillar-hosting potential. We measured avian predation rates during May, June, and October to compare caterpillar mortality in seasons that vary in life-history needs, abundance, and diversity of avian predators. We modeled daily survivorship and total mortality using Cox-proportional hazard models and logistic regression. We found that, across seasons, caterpillars had significantly higher predation rates on trees that are predicted by literature host records to support the most species of caterpillars (β = 0.22 ± 0.05, 95% CI = [0.13,0.32], z = 4.73, P < 0.0001). Caterpillars had the highest mortality in June, coinciding with avian breeding seasons, and the lowest rates in October, coinciding with fall migration and dispersal. Our study suggests that birds disproportionately forage on trees that have the highest potential to support caterpillar richness and presumably prey biomass. The observed pattern of non-random foraging has many implications; for example, the utility of using informed tree selection to improve bird foraging in managed ecosystems or potential negative implications to bird populations of forest-composition shifts due to climate change. Applying this information to habitat restoration will enable land managers to better support avian populations by planting trees that best support foraging substrates for insectivorous birds in managed ecosystems.

We conducted a detailed study of prey selection by a breeding pair of Falco columbarius (Merlin) on the Wells College campus in central New York. We identified prey from corpses and feathers (110 positive identifications from 112 prey items). Of the 16 prey species, swallows (35 Hirundo rustica [Barn Swallow], 7 Tachycineta bicolor [Tree Swallow], and 4 Stelgidopteryx serripennis [Northern Rough-winged Swallow]) predominated, comprising 41.8% of prey items (estimated 29.9% of biomass). Barn Swallows and Passer domesticus (House Sparrow) were the 2 most common species taken, both appearing throughout the nesting period (31.8% and 19.1% of prey items, respectively). As the season progressed, the proportion of juveniles taken increased to 90% by the latter half of July. We observed the female consuming the heads of freshly killed prey before plucking and delivering the food item to nestlings on 4 occasions, and we recovered 5 headless corpses of Merlin prey. We never found discarded heads of prey. These observations are in contrast to reports that Merlins typically discard the heads of prey. We propose nutritional explanations for selective consumption of the heads of prey by predatory birds. Five young fledged from our study nest, indicating high reproductive success. Our report of successfully breeding Merlins feeding principally on swallows is unique, and shows that the dietary emphasis on swallows did not compromise reproduction. Our results illustrate the flexibility of Merlins to local prey availability and reinforce the vulnerability of avian prey in open areas to Merlin predation.

Prey choice is the non-random foraging and consumption of prey species by their predators, and is therefore the basis for studies of topics as diverse as quantifying food webs, predator–prey relationships, and optimal-foraging models. Malaclemys terrapin (Diamond-back Terrapin) is a diet generalist with a large geographic distribution: the US Atlantic and Gulf coasts from Massachusetts to Texas. Individual terrapins have relatively small home ranges and feed primarily on local mollusc species. In feeding trials with 1 prey species and 2 prey species, wild-caught terrapins from New York readily consumed Mya arenaria (Soft-shelled Clam) and Geukensia demissa (Atlantic Ribbed Mussel), preferring them over a wide range of other prey species commonly eaten by terrapins at other sites. Our correlation test indicated that Ulva latuca (Sea Lettuce), common in the diets of this population, is ingested incidentally when terrapins forage for Soft-shelled Clams. The impact of consumption of algae by this primarily molluscivorous turtle is unexplored, but could have important impacts on their energy balance and contaminant intake.

We investigated ant species richness and abundance of the maritime forest and dune habitats of Assateague Island, a barrier island off the coasts of Maryland and Virginia. We paired 5 transects of 100 m in forest habitats with 5 transects in dune and grassland habitats, with pitfall traps set every 10 m along each transect. During a 5-month period (May–September), we collected 26 species of ants, including 9 that had not been previously recorded on the island and 2 that had never been recorded east of Maryland's Chesapeake Bay. Forest habitats had a significantly higher species richness than the dunes, with 24 and 14 species collected, respectively. Our research provides baseline data on ant species richness for this temperate barrier island using pitfall-collection methods. We provide evidence for forest habitats supporting higher species richness and make suggestions for future research.

The bryophyte flora of Virginia is vastly understudied compared to its vascular flora. Few instances of bryological investigation occurred in the state until interest rose in the 19^th and 20^th centuries. The full distribution of many common bryophyte species in the state remains incomplete due to a lack of field investigation. Here, we add to the knowledge of Virginia's bryophytes by documenting 39 total species of bryophytes from our study sites, including 15 new records of bryophyte species for Montgomery County. We made collections in an urban old-growth forest fragment and a secondary-growth forest on the campus of Virginia Tech. We devote special discussion to observations of 2 hepatic species and their ecological significance.

Floodplain forests provide valuable ecosystem services, yet human activity has degraded many of these riverine systems. Previous investigations of floodplain forest composition have frequently focused on flooding without incorporating successional dynamics; however, their restoration requires understanding both. We investigated floodplain forest composition along both flooding and succession gradients. River meandering builds new floodplain land with a variable microtopography and diverse levels of flood exposure. We compared vegetation to floodplain land ages on chronological sequences. Our results suggest that diverse species assemblages in floodplains result at least in part from geomorphic change. Ensuring that flood pulses continue to erode riverbanks and deposit sediments on sandbars and in floodplains is essential to the restoration and conservation of diverse forest assemblages in these ecosystems.