Numerous insect herbivores and leaf pathogens influenced seedling establishment of sugar maple (Acer saccharum) in six forests in central New York. The pear thrips (Taeniothrips inconsequens), an introduced pest of maples and orchard trees, was the primary mortality factor for seedlings in a sugar maple stand, although overstory defoliation by thrips was minor. At both sites where mortality was monitored, many emerging seedlings were killed in early spring by tortricid caterpillars, especially Clepsis melaleucana. Leaves of older seedlings were damaged by various caterpillars, Typhlocyba leafhoppers, Cristulariella depraedans leaf spot disease, and others. After the spring of their first year, seedling mortality decreased, and following mast years many new sugar maples were recruited into the seedling bank.

Garlic mustard (Alliaria petiolata) is a non-native invasive herb that has the potential to alter the understory plant community. We investigated the reproductive output of garlic mustard as a function of plant size and conspecific and heterospecific density in a central Ohio population. In general, taller plants produced more reproductive units (seeds, siliques). Density of conspecifics and heterospecifics had no effect on plant height or reproductive output. Reproductive output in our population of garlic mustard is lower and mean seed size is larger than most other populations for which data have been published, possibly because of the dry upland habitat of our population.

This paper investigated the potential for the exotic shrub Rhamnus frangula L. (glossy buckthorn) to alter native plant community composition in southeastern New Hampshire. Stratified random sampling was performed with 2 m × 2 m plots randomly located in 5 m intervals along three 50 m transects in four even-aged Pinus-mixed hardwood forests, three of which were managed stands. The associations between R. frangula and the measured species abundances and environmental variables were investigated using linear, least-squares multiple regression and Non-metric Multidimensional Scaling Ordination. Plot basal area of R. frangula was inversely related to woody seedling density (p < 0.001), herb cover (p < 0.05), and species richness (p < 0.01). The relative contribution of R. frangula to explaining variance in seedling density was greater than canopy openness, soil pH, soil clay, or soil sand. Abundance of R. frangula was a statistically significant predictor (p < 0.05) of individual herb species abundances for all study sites. This evidence supports the hypothesis that R. frangula causes a decline in seedling density and alters native ground level plant species abundances. Furthermore, the patterns agree with the suppression of ground level plant species abundances by R. frangula found in removal experiments.

We studied wintering populations of Mallards (Anas platyrhynchos Linnaeus) and American Black Ducks (A. rubripes Brewster) in urban parks in the industrial area of Cape Breton Island, Nova Scotia during December 1992 and January 1993 and during February and March, 1999–2002. Wintering flocks of Mallards and American Black Ducks have been fed in these parks for more than 30 years. We found that the numbers of American Black Ducks and Mallards have remained relatively stable for the last four years. No evidence exists that the population of Mallards was increasing nor that the population of American Black Ducks was decreasing. Numbers of ducks have fluctuated yearly, but numbers of these species have fluctuated synchronously. We conclude that numbers of American Black Ducks are not declining and are not being replaced by Mallards on Cape Breton Island. Furthermore, no evidence exists of genetic swamping because the proportion of hybrids in the local wintering population did not change.

We followed the annual use of a shallow coastal pond by molting Mute Swans to examine their potential impacts on waterfowl habitat. Effects of Mute Swan herbivory on submerged aquatic vegetation (SAV) and macroinvertebrates were measured by comparing control vs. exclosure plots in varying water depths from 1990 to 1994. Mute Swans fed in all water depths, but appeared to prefer feeding in shallow sites (< 0.5 m) where they were capable of reducing SAV biomass by up to 95%. The impact of Mute Swans on macroinvertebrates could not be demonstrated. Only three species of macroinvertebrates (Grammarus spp., Hydrobia spp., Limnephilus spp.) showed reduced densities on some grazed plots.

Prey selection and consumption of common molluscs and macroalgae by the Asian shore crab, Hemigrapsus sanguineus, were investigated in the laboratory. Crabs of three size classes (12–18, 19–25, 26–31 mm carapace width) collected from the rocky intertidal from May to November 1998, and were offered three mollusc species: the mussel Mytilus edulis, the clam Mercenaria mercenaria, and the snail Littorina littorea. Equal numbers of prey from three size classes or two species were offered concurrently to individual crabs. Crabs consumed small molluscs, large males opening larger molluscs than did females and smaller males. Male crabs consumed both mussels and clams. Females opened only mussels, but ate flesh from previously opened clams. Very few L. littorea were consumed. The macroalgae Codium fragile ssp. tomentosoides, Enteromorpha spp., Chondrus crispus, Fucus spp., and Ascophyllum nodossum were presented to individual crabs separately to determine consumption rates and together to ascertain species preference. Crabs preferred the green algae C. fragile ssp. tomentosoides and Enteromorpha spp.

During summer 2001 I consistently observed a group of 6 adult coyotes (the breeding female was radiocollared) raising 1 pup in a suburban area on Cape Cod, Massachusetts. In this note I describe the activities of this group and possible reasons for the large pack size.

In this paper, I review major historical conservation events, changes in landscape (cover types) patterns, and agency (state and federal) inventory and monitoring programs to help explain trends in terrestrial vertebrate populations in Pennsylvania. I then give recommendations for the long-term conservation of terrestrial vertebrates within the context of a future changing landscape in the Commonwealth. In Pennsylvania, the amount of forest has remained relatively constant since the 1970s, while the extent of early successional, grassland, and wetland/riparian habitats is declining. These trends, combined with direct human disturbance, degradation of water quality, and loss of critical habitat features have contributed to the endangered or threatened status of 31 vertebrate species in the state. Based on two major databases, the Pennsylvania Breeding Bird Survey and the Pennsylvania Breeding Bird Atlas, bird species occupying early successional, grassland, or wetland/riparian habitats, in particular, have generally shown negative trends in abundance and distribution, respectively. According to the Pennsylvania Gap Analysis Project, highest species richness or “hotspots” of mammals and birds are in areas with expanses of intact forest, as on public lands in the north central part of the state. The future conservation status of terrestrial vertebrates is contingent on several factors, ranging from wise stewardship of public and private lands to an understanding of the impacts of global climate change on vertebrate populations. Among the conservation recommendations are the need to improve connectivity among wildlands, understand the long-term impact of landscape changes on wildlife biodiversity, and develop databases on abundance and distributional trends of terrestrial vertebrate populations.