Historically, eastern ponderosa pine (Pinus ponderosa) forests were described as sparse patches of old-growth trees maintained by frequent, low-severity fires; however, in recent decades, there have been a number of large mixed-severity wildfires throughout the range of these forests. Wildlife responses to severe fire disturbance in eastern ponderosa pine forests are not well understood. Our study investigates how cavity-nesting bird species in an eastern ponderosa pine forest are impacted by burn severity. The objectives of our study were to: (1) identify the community composition of cavity-nesting birds in a 27 y old burn of mixed severity, (2) assess how habitat variables important to cavity-nesting birds differ in the mixed-severity fire, and (3) determine what habitat variables best predict bird occurrence 27 y after mixed-severity fire. We surveyed 56 sites across four burn severity classes, ranging from unburned to severely burned forest, in the Pine Ridge region of Nebraska. We measured multiple habitat characteristics (tree and snag diameter at breast height (DBH), coarse woody debris (CWD), tree and snag density, shrub height, and shrub cover) in May–August 2016 and conducted bird count surveys between 25 May and 8 June 2016. Cavity-nesting bird species' occurrence varied among the burn severity variables. Burn severity class (unburned, low severity, moderate severity, high severity) was a significant predictor of habitat characteristics for cavity-nesting birds, including tree density, snag density, mean snag DBH, variance in DBH, and CWD, which also was the best indicator of cavity-nesting bird community composition. We report evidence that mixed-severity wildfires in eastern ponderosa pine forests create variation in habitat characteristics and cavity-nesting bird occurrence.

For most passerines, survival and behavior during the postfledging period are poorly known, even though these population characteristics are potentially important to demography and conservation. In 2013–2014 radiotelemetry was used to measure survival, movements, and habitat use of juvenile Veeries (Catharus fuscescens) during the postfledgingdependent period in a landscape dominated by mature forest in northeastern Pennsylvania. In total I tracked 29 juvenile Veeries and conducted habitat sampling at sites used by fledglings and at associated random sites. Survival during the first 21 d postfledging was high (0.78), with most mortalities occurring during the first 7 d, and all deaths attributed to predation. Fledglings moved gradually away from their nests as they aged, averaging 333±62 m by 19–21 d. However, there was much variation in movement patterns among individuals, perhaps reflecting differences in spatial distribution of important microhabitats or differences in timing of postfledging dispersal. Like fledglings of many other species of forest passerines, Veery fledglings preferred microhabitats with dense woody understory vegetation: compared to random sites, sites used by fledglings had, on average, greater woody ground cover, midstory cover, and sapling density but had lower density of eastern hemlock trees. However, unlike many other forest passerine species, Veery fledglings did not exhibit broad shifts to other nonnesting habitat types. These results provide the first detailed study of postfledging survival and behavior of the Veery and add generally to our understanding of postfledging ecology in forest passerines.

Agricultural development may produce highly fragmented landscapes, which can influence population genetic structure for organisms restricted to insularized breeding habitats. Common Nighthawks (Chordeiles minor) in agriculturally dominated landscapes nest on urban gravel rooftop and might be subject to reduced gene flow among isolated urban sites. We conducted an analysis of the genetic variability and population genetic structure of Common Nighthawks nesting on rooftops in four towns in southeastern South Dakota, an area that has experienced extreme conversion of native prairie to agriculture. Using sequence data from a 725 bp region of the cytochrome b (cytb) mitochondrial gene sampled from 37 individuals representing a total of 30 different nests collected in summers 2014–2016, we found evidence of a recent population bottleneck and reduced mtDNA variability. The spatial dispersion of the 14 detected haplotypes and the presence of nine haplotypes unique to one of the four sampled towns further suggested a lack of panmixia among these nighthawks. These data are consistent with a hypothesis of habitat fragmentation due to agricultural expansion resulting in population isolation within this species of conservation concern.

We examined relationships between nest success and attributes of brood crevices in rock outcrops used by green salamanders (Aneides aeneus) on the Blue Ridge Escarpment from 2010 to 2015. We used data from a long-term monitoring program by the North Carolina Wildlife Resources Commission and defined nest success as evidence of at least one egg hatching in a clutch. We georeferenced all rock outcrops with nesting green salamanders and calculated straight-line distances to closest outcrops with nesting green salamanders using ArcGIS. A total of 2578 rock outcrops during six nesting seasons were surveyed to determine nest success for 168 nests in 88 crevices from 74 outcrops. Where all crevices could be thoroughly surveyed, attributes of brood crevices (N = 29) and corresponding random crevices at 29 rock outcrops were quantified. Nest success during the 6 y period ranged from 73–92% and was not related to year or any crevice attribute. There was a negative relationship between nest success and straight-line distance to outcrop with nesting green salamanders, and crevices that contained one successful nest were more likely to have a successful nest in another year. Females selected brood crevices that were higher above the ground and shorter in length than those randomly available on the outcrop. These results suggest that the odds of a green salamander having a successful nest decrease as the distance to the closest rock outcrop with other nesting individuals increases. Female green salamanders select brood crevices with attributes that likely minimize direct competition and nest predation from other species of salamanders as well as other predators in general.

Chemical cues are frequently a key source of information to aquatic organisms. Both predators (kairomones digestive metabolites) and prey (alarm and damage-released cues) may generate chemical cues during their interactions, and different cue types can have different informational values. How predators and prey use the information from chemical cues to make spatial movement decisions influences both their direct interaction rates and their interactions with other species. We measured the spatial response of predatory larval dragonflies (Anax junius) and predator-naïve green frog (Lithobates clamitans) tadpoles exposed to several types of chemical cues using experimental mesocosms. We found tadpoles only responded with spatial avoidance when exposed to both Anax kairomones and conspecific alarm cues together, whereas Anax did not exhibit consistent spatial responses to any cue type. Our results suggest tadpole prey selectively respond to environmental information from chemical cues (possibly to minimize costly antipredator behavior due to responding to insufficient information or reflecting a need for associative learning). They also show predatory dragonflies may use nonchemical information to make space use decisions (possibly due to inability to detect the same chemical cues as tadpoles).

Louisiana's streams provide habitat for a diversity of ecologically and economically important fish species. However, most stream systems in the state have been subject to substantial anthropogenic alterations related to municipal, agricultural, and forest resource development. Extensive reservoir construction has also resulted in altered dendritic connectivity in many drainages, which has been shown to significantly alter the function and biodiversity of streams throughout the U.S. This study explored interactions among stream connectivity, watershed characteristics, stream physicochemistry, and fish assemblage composition and abundance in 21 headwater streams within the Red River basin of Louisiana, with half flowing directly into a reservoir. In 2014 and 2015, fish were sampled by electrofishing and seining, and habitats and physicochemistry were characterized. Six fish species were exclusively found in reservoir streams, three fish species were only found in river tributaries, seven fish species were more abundant in river tributaries, and all richness metrics (total, stream specialist, and generalist) calculated for seined fishes were higher in river tributaries. Notably, Grass Pickerel (Esox americanus) was more abundant in river tributaries. Because of its potential role as an obligate glochidial host for the Louisiana Pearlshell Mussel (Margaritifera hembeli), the influence of stream fragmentation on Grass Pickerel may have significant implications regarding conservation of this endangered mussel. Our results parallel trends observed in similar studies indicating decreased species richness and abundance in streams truncated by reservoirs.

In 2017 we sampled tree stems in a clearcut generated in 1977 in the Pigeon River State Forest, Michigan and compared results to three previous sampling periods completed in 1983, 1988, and 1999, respectively. Trees were recorded by species, height class, and whether or not stems had been browsed by mammalian herbivores and whether stems were alive or dead. The results show the most preferred browse tree species when the clearcut was young (bigtooth aspen) was completely absent by 1999 and thereafter, and tree species richness increased over time. Elk were still using the area in 2017, as shown by the presence of pellet groups and sightings in the clearcut and nearby, but little noticeable browse damage was seen in 1999 or 2017, and tree mortality was negligible in 2017. A total of 22 tree species were identified across the time period, but only five species were recorded as present in all years. A total of 11 species were recorded in 1 y only: six in 1999 and five in 2017. Many species were rare, as defined by relative abundances of <0.01, and relative abundances varied a great deal across time. Stochastic dispersal, establishment, and mortality events likely explain many of these observations, given high mortality rates of seedlings and small saplings due to browsing earlier in succession, and competition for light or other resources as trees aged over time.

This study examines the capacity of two nonnative lumbricid earthworms, Lumbricus terrestris and L. rubellus, to ingest and digest the seeds of herbaceous plants and affect their distribution in forest soils of northeastern Ohio. A survey of earthworms in a forested area of Cleveland Metroparks revealed Lumbricus was the most common and widely distributed earthworm genus, although Aporrectodea and Octolasion were also well represented. A total of 120 soil samples taken adjacent to earthworm sampling plots and placed in a growth chamber yielded a total of 35 germinations. The germinations occurred primarily in the upper 8 cm of the soil profile, suggesting limited redistribution of seeds by earthworms. Growth chamber feeding trials using seeds ranging in size from approximately 2 to 5 mm maximum linear dimension revealed that both species of earthworm will consume and digest seeds that measure up to between 3 and 4 mm. Lumbricus terrestris consistently ingested and digested more than twice as many seeds as did the substantially smaller L. rubellus. Comparisons of the germination rates of seeds egested by the earthworms with rates for seeds that were not ingested showed no impact on germination due to egestion, suggesting ingestion and subsequent egestion of seeds by lumbricid earthworms does not enhance germination. By ingesting and digesting seeds, L. rubellus and L. terrestris should reduce the number of viable seeds in the soil and, thereby, contribute to changes in forest vegetation.

Coreopsis tinctoria (Asteraceae) is a widely-distributed North American prairie flowering C₃ annual. We hypothesized priority effects of planting C. tinctoria before a C₄ grass would decrease interspecific competition. Coreopsis tinctoria was grown in south-central Texas (29°35′N, 98°37′W) with Bouteloua curtipendula (Poaceae), a widespread C₄ prairie grass. The two species were planted in a de Wit replacement series with plant ratios of 12:0, 10:2, 8:4, 6:6, 4:8, 2:10, and 0:12 (C. tinctoriaa: B. curtipendula). There were five planting offsets with C. tinctoria planted 60 d before B. curtipendula (–60), 30 d before (–30), at the same time (0), 30 d after (30), and 60 d after (60). There were significant species by offset, species by frequency, and offset by frequency interactions. Coreopsis tinctoria produced the greatest total dry mass per plant in the 60 d before offset. Coreopsis tinctoria was competitively favored when planted 60 d before B. curtipendula and B. curtipendula was favored when planted 30 and 60 d before C. tinctoria. Results suggest a synergistic benefit from both spatial gaps and priority effects.

The composition and dominance of 1256 witness (land survey) trees were compiled for the early Colonial era (pre-1700) in two locations in eastern Virginia, a region where studies of such information are lacking. The study locations are the Marine Corps Base Quantico and the Cheatham Annex Naval Supply Center, both along major rivers of Tidewater Virginia. At Quantico, a total of 754 witness trees comprising 22 species were recorded. Oak (Quercus) species made up 67% of these trees, followed by hickory (Carya; 15%), poplar (Liriodendron), gum (Nyssa), and pine (Pinus) each representing 4% of the forest composition. At Cheatham Annex a total of 502 witness trees from 24 species were recorded. Oaks made up 57% of the total composition followed by hickory (13%), pine (10%), poplar (5%), and gum (5%). There was a dearth of late successional, fire sensitive species at both locations, despite the presence of many mesic locations that should support such species. This suggests Native American activity (e.g., burning and land clearing) was an important factor affecting forests in eastern Virginia. This research provides a better understanding of the original forests of eastern Virginia and can serve as a baseline for making comparisons with present day forests to assess forest change since the Colonial era.

Kokanee salmon are a dwarf freshwater form of the anadromous sockeye salmon (Oncorhynchus nerka) native to the Pacific coast of North America and Asia and widely introduced in western North America as a sport and prey fish. Few kokanee salmon introductions have succeeded in eastern North America. A naturalized population of kokanee salmon has persisted for over 50 yr in Florence Lake, Wisconsin, an unlikely location given its relatively small size (21.4 ha), shallow maximum depth (7.6 m), low elevation (381 m), and southerly latitude (45.12°N). Kokanee salmon completed their entire life cycle within the lake and rarely entered an accessible coldwater inlet stream. Spawning occurred during late October and early November along the lake shoreline. Spawning redds with defending males were observed in 1–2 m of water on sand/gravel/ cobble substrate. Kokanee salmon growth in the lake was relatively rapid, and fish had a mean total length of 117 mm after their first growing season (age 0+), 212 mm after their second (age 1+), begin to mature and spawn after their third (age 2+) at 317 mm for females and 324 mm for males, and were at 344 mm for females and 354 mm for males after their fourth (age 3+). Few fish reproduced at age 4+. Despite limited oxy-thermal habitat during summer, kokanee salmon appear to thrive in Florence Lake, perhaps because of cold inflows from the inlet and springs within the lake.

Animal coloration has adaptive roles for communication, concealment, sexual selection, and physiological function. Genetic mutations sometimes cause abnormal coloration such as leucism, in which an animal appears partially or entirely white, except for exposed soft skin tissue. Here we document a leucistic fisher (Pekania pennanti). Fisher fur normally ranges from deep brown to black, but the function of the pelt color is not understood. The literature on the occurrence of leucism includes 33 other records of leucism among carnivores. Reporting cases of rare coloration in the wild helps to understand the distribution, prevalence, and significance of abnormal colors.

While once dismissed as an artifact of unnatural laboratory conditions, cannibalism is now widely accepted as a common behavior exhibited by multiple insect taxa, including primarily herbivorous species. In some cases cannibalism provides a means of acquiring nutrients and defensive compounds, reducing competition, and decreasing population density. For plants, inducing insect cannibalism is a defense mechanism to decrease damage by pests. Despite the growing awareness of cannibalism, its causes, and its ecological importance, few model systems exist, largely because observations of cannibalism are not reported. Here, we investigated the cannibalism of pupae by caterpillars of the ranchman's tiger moth, Arctia virginalis, [Lepidoptera: Erebidae] based on an observation of a late instar caterpillar attacking the pupa of a conspecific in our laboratory. We conducted separate laboratory and field experiments to confirm this observation and determine the propensity for cannibalism under more natural conditions. We confirmed our observation of cannibalism in the laboratory experiment but failed to detect evidence of this behavior in the field. Consequently, the frequency of cannibalism, the conditions under which it occurs, and its impact on the population dynamics of A. virginalis are still unknown.