116 research outputs found
Populations and Breeding Schedules of Waders, Charadrii, in High Arctic Greenland, by Hans Meltofte
Two Vascular Plants New to Nova Scotia: Yellow Glandweed (Parentucellia viscosa (L.) Caruel) and Whorled Loosestrife (Lysimachia quadrifolia L.)
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
Plants and Insects New to Sable Island, Nova Scotia
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, Carex nigra, Frangula alnus, Isoetes tuckermanii, Linaria vulgaris, Mertensia maritima, Panicum dichotomiflorum, and Solidago rugosa. Additions to the insect fauna include Apateticus bracteatus, Barce fraterna, Carabus maeander, Conocephalus fasciatus, Danaus plexippus, Eulithis explanata, Haliplus cribrarius, Harmonia axyridis, Lasioglossum novascotiae, Lateroligia ophiogramma, Lycophotia phyllophora, Muirodelphax arvensis, Nemoria rubrifrontaria, Neoconocephalus retusus, Paraphlepsius irroratus, Scaphytopius acutus, and Spilodiscus 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
Comparison of the Ground Vegetation in Spruce Plantations and Natural Forest in the Greater Fundy Ecosystem, New Brunswick
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. Nonindigenous 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
Effects of Timber Harvesting and Plantation Development on Cavity-nesting Birds in New Brunswick
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
Road-kill of Mammals in Nova Scotia
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 more 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
Breeding Bird Surveys at Alexandra Fiord, Ellesmere Island, Nunavut (1980–2008)
Long-term monitoring of bird populations in the Arctic is of considerable interest as this area is experiencing rapid climate warming; however, multi-decadal studies in the Canadian High Arctic are rare. Over five summers between 1980 and 2008, we conducted breeding bird surveys by walking transects and mapping territories in a periglacial lowland on east-central Ellesmere Island, Nunavut. In all survey years, snow bunting (Plectrophenax nivalis), Lapland longspur (Calcarius lapponicus), and Baird's sandpiper (Calidris bairdii) were the most abundant species. Over the study period, the assemblage of breeding bird species appears to have changed little, except for an increase in Lapland longspur. In the summer of 2008, we also compared two techniques for censusing territories. We found that spot-mapping, a simple and cost-effective method, produced similar results to the more labour-intensive active-flushing. Spot-mapping is therefore suitable for conducting bird surveys in northern locations where the vegetation is short, the terrain is flat, and the visibility is extensive. In the coming years, it will be important to continue monitoring Arctic birds to determine how climate change is affecting their breeding populations.La surveillance à long terme des populations d'oiseaux de l'Arctique revêt un intérêt considérable à la lumière du changement climatique rapide que connaît cette région. Cela dit, il faut remarquer que peu d'études échelonnées sur plusieurs décennies ont été réalisées dans l'Extrême-Arctique canadien. Au cours de cinq étés répartis entre 1980 et 2008, nous avons effectué le dénombrement d'oiseaux nicheurs en traversant des transects et en cartographiant des territoires situés sur les basses terres périglaciaires de l'île d'Ellesmere, au Nunavut. Au cours de toutes les années visées par le dénombrement, le bruant des neiges (Plectrophenax nivalis), le bruant lapon (Calcarius lapponicus) et le bécasseau de Baird (Calidris bairdii) se sont avérés les espèces les plus abondantes. Au cours de la période visée par l'étude, l'assemblage d'espèces d'oiseaux nicheurs semble avoir peu changé, sauf pour ce qui est d'une augmentation de bruants lapons. À l'été 2008, nous avons également comparé deux techniques de recensement des territoires. Nous avons effectivement constaté que la méthode des plans quadrillés, une méthode simple et abordable, donnait des résultats semblables à la méthode de dispersion active qui demande beaucoup plus de travail. Par conséquent, la méthode des plans quadrillés convient bien à la réalisation de recensements d'oiseaux dans les emplacements nordiques où la végétation est courte, où le terrain est plat et où la visibilité est vaste. Au cours des années à venir, il sera important de continuer à surveiller les oiseaux de l'Arctique afin de déterminer quelles sont les incidences du changement climatique sur les populations d'oiseaux nicheurs
Nuclear Physics Neutrino PreTown Meeting: Summary and Recommendations
In preparation for the nuclear physics Long Range Plan exercise, a group of
104 neutrino physicists met in Seattle September 21-23 to discuss both the
present state of the field and the new opportunities of the next decade. This
report summarizes the conclusions of that meeting and presents its
recommendations. Further information is available at the workshop's web site.
This report will be further reviewed at the upcoming Oakland Town Meeting.Comment: Latex, 31 pages. This version has been updated to include final
Comments from the working group
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