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To provide necessary information for the management of biodiversity on Sable Island, Nova Scotia, we studied the effects of feral horses on vegetation using exciosures and ancillary observations. Nine plant communities inside and outside of six exclosures were compared using various vegetation parameters and Mann-Whitney tests to evaluate the significance of dif- ferences. The most important findings were as follows: (1) effects of horses were greatest in the Marram (Ammophila bre- viligulata) grassland and much less in the communities that were not dominated by Marram Grass; (2) effects on Marram grassland varied substantially among sites; (3) the cover of standing litter of herbaceous plants was on average of 9.3 times greater inside exclosures in grassland habitats; (4) the cover of living foliage was usually higher inside exclosures, but not all differences were significant; (5) species richness and species diversity were not substantially affected; (6) the average cover of Marram Grass, the most abundant plant and a key sand binder on the island, was greater inside exclosures in six of seven study sites, significantly so in three of them; and (7) there were inconsistent differences in cover of other species at different sites. Wetland habitats cover a relatively small portion of Sable Island, but they support much of the plant biodiver- sity. There is evidence of strong but variable effects of horses on wetland vegetation. "Horse lawns" are littoral habitats dominated by Agrostis stolonifera (Carpet Bentgrass) and other low-growing plants. The lawn habitats represent less than 1% of the island's vegetation, and their presence is believed to be due to grazing and trampling by horses. [ABSTRACT FROM AUTHOR]

During recent inventories, particularly in 2008 and 2009, 8 plants and 17 insects were found that are additions to the flora and fauna of Sable Island, respectively. Additions to the flora include Alnus incana subsp. rugosa, Garex nigra, Frangula alnus, Isoetes tucker,nanii, Linaria vulgaris, Mertensia rnaritinla, Panicum dichotomiflorum, and Solidago rugosa. Additions to the insect fauna include Apateticus bracteatus, Barce fraterna, Carabus nzaeander, Conocephalus fasciatus, Danaus plexippus, Eulithis explanata, Haliplus cribrarius, Harnionia axyridis, Lasioglossuin novascotiae, Lateroligia ophiogromma, Lycophotia phyllophora, Muirodelphax arvensis, Nemoria rubr,frontaria, Neoconocephalus retusus, Paraphiepsius irmratus, Scaphytopius acutus, and Sj,ilodiscus arcuatus. The occurrence of Spilodiscus arcuatus is of interest with respect to an apparent decline throughout much of its range. Neoconocephalus retusus and species of Catocala provide an indication of the capability of storms to transport even large insects over substantial distances. The increasing numbers of Danaus plexippus observed may be part of a trend toward the northward movement of migratory insects. Some of the 7 plants are likely recent arrivals, but Isoetes tuckermanii and others may have been previously overlooked. [ABSTRACT FROM AUTHOR]

We examined road mortality of wild mammals in Nova Scotia using data from (a) five years of province-wide data on wildlife collisions involving larger mammals, and (b) 20 months of observations of smaller mammals along a 160-km route near Halifax. An average of 2079 White-tailed Deer was reported killed annually on highways during 1999 through 2003, along with 14 Moose and 33 Black Bear. Female White-tailed Deer were mole likely to be road-killed than males (by a factor of 1.8), yearlings more so than older animals, and there were peaks of mortality in the late spring and late autumn. The road-kill of smaller mammals was highest in the summer and least in the winter, and the most frequent mortalities were of Raccoon (28% of observations), Porcupine (27%), Skunk (17%), Snowshoe Hare (6%), Coyote (4%), and Groundhog (3%). The standardized kill-rate (number/100 km) was highest on a 100-series highway compared to trunk highways or urban streets, but the rate standardized to vehicle density was highest on trunk highways. [ABSTRACT FROM AUTHOR]

We studied the abundance of cavity-nesting birds in forestry-related habitats in a region of Acadian forest in New Brunswick. We examined five reference stands of natural forest, a chronosequence of conifer plantations up to 19 years old (the oldest in the study area), two selectively harvested stands, and a 30-year-old naturally regenerated clear-cut. The species richness and abundance of cavity-nesting birds were higher in reference forest (average 10.0 species per stand; 5.3 territories per 10 ha) than in plantations (2.3/stand; 1.0/10 ha), selectively harvested stands (7.0/stand; 3.8/10 ha), or the naturally regenerated clear-cut (5.0/stand; 2.5/10 ha). A cluster analysis segregated the "community" of cavity-nesting birds of natural forest from those of other treatments. Of the various harvested stands and plantations, five with a relatively large number of residual snags clustered similarly in the cluster analysis, while those with no or very few snags also clustered together. We used arrays of nest boxes (12 per stand) to examine whether the availability of cavities was limiting the use of habitats otherwise suitable for foraging by cavity-dependent species. Nest-box use for nesting and roosting was much higher in the seven plantations examined (average 4.0/10 ha for nesting and 2.9/10 ha for roosting) than in three reference stands (each 0.3/10 ha), suggesting that the plantations were deficient in this critical-habitat element. Our results suggest that certain mitigations, such as leaving residual snags and living cavity-trees, would help maintain populations of some cavity-dependent birds in clear-cuts and plantations. However, some cavity-dependent species might not be accommodated by these mitigations and are potentially at risk in intensively managed areas, unless landscape-scale management plans ensure the survival of sufficient areas of older mixed-wood forest. [ABSTRACT FROM AUTHOR]

We studied changes in ground vegetation associated with the conversion of natural, mature, mixed-species forest into conifer plantations in southeastern New Brunswick. This was done to determine the degree to which plant-associated biodiversity was affected by this forestry practice. Species of lichens, bryophytes, and vascular plants were examined in a 21-year chronosequence of 12 Black Spruce (Picea mariana) plantations and compared to 8 stands of natural forest of the type replaced. The richness, diversity, and density of species were greatest during younger stages of the plantation sere, with as many as 170 species occurring in a 6-year-old stand. Species occurred in successional stages according to their abilities to: (a) survive disturbances associated with clear-cutting and plantation establishment; (b) regenerate vegetatively; (c) re-establish from a persistent seedbank; (d) invade disturbed habitat by dispersed seeds; and/or (e) tolerate environmental stress imposed by the overtopping canopy during stand development. Multivariate analyses suggested that successional factors had the strongest influence on differences in the ground vegetation among stands of various ages. Gaps in the canopy of reference forest and older plantations provided microsite conditions similar to those of early seral stages, allowing some ruderal species to persist in older stands. Non-indigenous species were almost entirely limited to younger plantations. Some species of natural forest were rare or absent from plantations and may be at risk from the extensive development of these agroforestry habitats in our study region; these included Acer pensylvanicum, Cephaloziella spp., Chiloscyphus spp., Fagus grandifolia, Lepidozia reptans, Nowellia curvifolia, Odontoschisma denudatum, and Viburnum alnifolium. [ABSTRACT FROM AUTHOR]

Presents a study that investigated birds breeding in conifer plantations in the vicinity of Fundy National Park in New Brunswick. Analysis of birds in natural, mixed-species forest of the type that has not been clear-cut and converted into plantations; Summary of bird community variables; Variations of the distribution and abundance of birds.

Yellow Glandweed (Parentucellia viscosa (L.) Caruel), found near Yarmouth, and Whorled Loosestrife (Lysimachia quadrifolia L.), found near Halifax, are reported as new to Nova Scotia. The former is also new to the Atlantic coast of North America. [ABSTRACT FROM AUTHOR]

Amphibians were sampled during two growing seasons in a variety of terrestrial habitats in the vicinity of Fundy National Park, New Brunswick. Four sampling methods were used: pitfall transects, pitfall arrays, quadrat searches, and time-constrained searches. Pitfall arrays sampled the greatest relative abundance and species richness of amphibians. However, quadrat searches were better at sampling Plethodon cinereus (Red-backed Salamander), a wholly terrestrial species. [ABSTRACT FROM AUTHOR]