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The Nonindigenous Aquatic Species Database (NAS) information resource is an established central repository for spatially referenced biogeographic accounts of introduced aquatic species. The NAS website provides scientific reports, online/real-time queries, spatial data sets, distribution maps, fact sheets, and general information.
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In the contiguous United States there are approximately 5 million kilometers of streams and rivers, which contain a diversity of aquatic species including microbes, aquatic vegetation (algae and plants), invertebrates, and fish, all of which play key roles in structuring the food web that sustains aquatic life, wildlife, and in some cases humans. Over the last 50 years, human actions have profoundly altered the natural input and cycling of nutrients (nitrogen and phosphorus) through the environment and greatly increased the amount of nutrients transported to our streams, rivers, and estuaries. Although nutrients are essential for a healthy aquatic ecosystem, excess nutrients can affect aquatic and human health....
In the White River basin, water demand has increased with human development. Water development projects impact White River hydrology and sediment transport which can, in turn, affect resident Colorado pikeminnow populations. The objectives for this study were: 1) to compile historical biological, hydrological and physical data for the White River, 2) to analyze physical, chemical and biological features of the White River important to endangered fishes and, 3) to identify parameters for long-term monitoring to insure these features are maintained. We examined physical, chemical and biological characteristics during three development periods in the UCRB: early (1895-1945), middle (1946-1984) and post Taylor Draw...
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A phylogenetic analysis of 19 sibling taxa in the Vertigo gouldii group was conducted on 73 individuals sampled across North America using DNA sequence data of the mitochondrial genes cytochrome oxidase subunit 1 (CO1) and 16S ribosomal RNA (16S), and the internal transcribed spacer-2 of the nuclear ribosomal RNA (ITS-2) gene. The results of these analyses were found incongruent with previous taxonomic concepts used to define the V. gouldii group and its composite taxa that were based entirely on conchological features. The mtDNA sequence data suggest that some previous members of the traditional V. gouldii group may be more closely related to V. modesta. They also suggest that V. gouldii may itself consist of seven...
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Direct density-dependence through intraspecific competition may be an important mechanism permitting sustained herbivore outbreaks. In theory, interference competition could allow a relatively stable number of herbivore individuals to survive while moderating host plant damage. This research examined the potential role of intraspecific competition in permitting a decade-long outbreak of the aspen leaf miner, Phyllocnistis populiella, on Populus tremuloides in interior Alaska. A combination of observational and experimental studies examined larval food requirements, food resources, and the impacts of P. populiella larval density on survival, mass, and leaf mining damage. These results were then compared to those...
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Introduction: ... As a directed effort to further document moths of limited geographic occurrence, an initial inventory of the southwestern Yukon was conducted in 2004. Survey efforts focused on habitats known to harbor species of limited occurrence, particularly sand dunes and low elevation grasslands / steppe. Alpine tundra was also surveyed, but to a lesser extent owing to the fact that many of the Beringian endemic species have a biennial life cycle and fly only in odd-numbered years (Lafontaine & Wood 1997). Although Yukon's boreal habitats are undoubtedly home to many species not yet documented from this territory, the boreal fauna is generally transcontinental in distribution, and survey work was not explicitly...
Groundwater-fed streams are typically hotspots of aquatic biodiversity within glacierized catchments. Surface water physicochemistry and macroinvertebrate communities within five groundwater-fed streams were characterised across catchments in Denali National Park, interior Alaska. The main aim of this study was to assess whether hydrological controls on macroinvertebrate communities (e.g. flow permanence) identified within previous catchment-specific studies are present at wider spatial scales, across multiple groundwater-fed streams located on alluvial terraces within glacierized catchments. Macroinvertebrate community diversity, in general, was shown to be high and relatively invariant across the groundwater-fed...
Direct density-dependence through intraspecific competition may be an important mechanism permitting sustained herbivore outbreaks. In theory, interference competition could allow a relatively stable number of herbivore individuals to survive while moderating host plant damage. This research examined the potential role of intraspecific competition in permitting a decade-long outbreak of the aspen leaf miner, Phyllocnistis populiella, on Populus tremuloides in interior Alaska. A combination of observational and experimental studies examined larval food requirements, food resources, and the impacts of P. populiella larval density on survival, mass, and leaf mining damage. These results were then compared to those...
An atlas detailing state and provincial distributions of 663 North American Ephemeroptera species is presented. Biogeographic affinities of 95 North American genera are discussed and their hypothesized origins reviewed. Historical events in regards to vicariance and dispersal were important factors influencing the evolution of the North American fauna. Lineages found in North America are a result of Northern Hemisphere vicariant events (e.g., plate tectonics) and periods of dispersalist invasion, notably via the Isthmus of Panama and Beringia. The North American fauna is composed predominantly of Nearctic endemics/relicts, and lineages with Laurasian or Neotropical affinities. Although Cloeodes and Ephoron are hypothesized...
Free-ranging ungulates in North America are host to over 50 species of parasitic gastrointestinal nematodes (strongyles), many of which vary in their pathogenicity and response to anthropogenic and climatological disturbance. Consequently, species-specific identification is crucial to understanding the epizootiology of strongyles in wildlife. I validated a molecular assay (PCR-SSCP) for species-level differentiation of strongyles, and used this approach to help describe strongyle communities in western Canadian cervids. Three new host and ten new geographic records were described. Deer ( Odocoileus spp.) harboured a high diversity of strongyles with a distinct geographic partitioning of species. Prevalence of infection...
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The Nonindigenous Aquatic Species Database (NAS) information resource is an established central repository for spatially referenced biogeographic accounts of introduced aquatic species. The NAS website provides scientific reports, online/real-time queries, spatial data sets, distribution maps, fact sheets, and general information.
map background search result map search result map Impact of epidermal leaf mining by the aspen leaf miner ( Phyllocnistis populiella) on the growth, physiology, and leaf longevity of quaking aspen 2004 moth survey for southwestern Yukon Short-Term Demographic Response of the Red-Backed Vole to Spruce Beetle Infestations in Alaska Spruce beetles and forest ecosystems in south-central Alaska: A review of 30 years of research Evolutionary pattern and process within the Vertigo gouldii (Mollusca: Pulmonata, Pupillidae) group of minute North American land snails The role of interference competition in a sustained population outbreak of the aspen leaf miner in Alaska Mechanisms of aquatic species invasions across the South Atlantic Landscape Conservation Cooperative region The quality of our Nation’s water—Understanding the influence of nutrients on stream ecosystems in agricultural landscapes—supplemental data An inter-catchment assessment of macroinvertebrate communities across groundwater-fed streams within Denali National Park, interior Alaska Cryptic subarctic diversity: a new bumblebee species from the Yukon and Alaska (Hymenoptera: Apidae) Impact of epidermal leaf mining by the aspen leaf miner ( Phyllocnistis populiella) on the growth, physiology, and leaf longevity of quaking aspen The role of interference competition in a sustained population outbreak of the aspen leaf miner in Alaska Short-Term Demographic Response of the Red-Backed Vole to Spruce Beetle Infestations in Alaska An inter-catchment assessment of macroinvertebrate communities across groundwater-fed streams within Denali National Park, interior Alaska Spruce beetles and forest ecosystems in south-central Alaska: A review of 30 years of research 2004 moth survey for southwestern Yukon Mechanisms of aquatic species invasions across the South Atlantic Landscape Conservation Cooperative region Cryptic subarctic diversity: a new bumblebee species from the Yukon and Alaska (Hymenoptera: Apidae) Evolutionary pattern and process within the Vertigo gouldii (Mollusca: Pulmonata, Pupillidae) group of minute North American land snails The quality of our Nation’s water—Understanding the influence of nutrients on stream ecosystems in agricultural landscapes—supplemental data