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This dataset contains single nucleotide polymorphism (SNP) information for aquatic insect species collected in tributaries of the Colorado River in Grand Canyon (Arizona, USA), as well as SNP information for individuals collected from reference reaches of the Upper Colorado River Basin in Utah. This dataset focuses specifically on three species that were common and widely distributed throughout tributary streams in Grand Canyon: a mayfly (Fallceon quilleri), a caddisfly (Hydrospyche oslari), and a water strider (Rhagovelia distincta).
Synopsis: This study aimed to independently examine the effects of varying amounts and configurations of habitat at a landscape scale, with particular attention to critical persistence thresholds. A discrete reaction-diffusion model was used to estimate long-term equilibrium population persistence of a hypothetical species in a patchy landscape. When examined over a broad range of habitat amount and arrangements, population size was largely determined by the proportion of habitat (amount) in a landscape. However, when habitat coverage dropped below 30-50%, population response deviated, coinciding with a persistence threshold. Species persistence declined rapidly at this threshold range (50% for low degrees of aggregation,...
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Conclusions: The nature of the surrounding matrix contributes significantly to the degree of patch isolation; matrix modification may improve habitat connectivity and genetic distribution in fragmented landscapes. Thresholds/Learnings: Synopsis: This study challenges traditional assumptions about the uniform nature of the matrix, and the reliance on distance alone as an indicator of patch isolation, by testing whether the type of inter-patch matrix contributes significantly to patch isolation in butterfly populations. The author tracked the movement of six butterfly species between patches of meadow habitat through two natural matrix types (conifer forest and willow thicket). All taxa of butterflies studied responded...
Wind is suspected to be a primary dispersal mechanism for large branchiopod cysts on the Colorado Plateau. We used a wind tunnel to investigate wind velocities capable of moving pothole sediment and cysts from intact and disturbed surfaces. Material moved in the wind tunnel was trapped in filters; cysts were separated from sediment and counted. Undisturbed sediment moved at velocities as low as 5.9 m s?1 (12.3 miles h?1). A single all-terrain vehicle (ATV) track increased the sediment mass collected 10-fold, with particles moving at a wind velocity of only 4.2 m s?1 (8.7 miles h?1). Cysts were recovered from every wind tunnel trial. Measured wind velocities are representative of low-wind speeds measured near Moab,...
A two-dimensional hydrodynamic model was applied to seven study reaches in the Colorado River within Grand Canyon to examine how operation of Glen Canyon Dam has affected availability of suitable shoreline habitat and dispersal of juvenile humpback chub (Gila cypha). Suitable shoreline habitat typically declined with increasing discharges above 226?425m3/ s, although the response varied among modelled reaches and was strongly dependent on local morphology. The area of suitable shoreline habitat over cover types that are preferred by juvenile humpback chub, however, stayed constant, and in some reaches, actually increased with discharge. In general, changes in discharge caused by impoundment tended to decrease availability...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0006320712004387#): An understanding of how stressors affect dispersal attributes and the contribution of local populations to multi-population dynamics are of immediate value to basic and applied ecology. Puma ( Puma concolor) populations are expected to be influenced by inter-population movements and susceptible to human-induced source–sink dynamics. Using long-term datasets we quantified the contribution of two puma populations to operationally define them as sources or sinks. The puma population in the Northern Greater Yellowstone Ecosystem (NGYE) was largely insulated from human-induced mortality by Yellowstone National Park. Pumas in the western...
Abstract: Accelerating climate change and other cumulative stressors create an urgent need to understand the influence of environmental variation and landscape features on the connectivity and vulnerability of freshwater species. Here, we introduce a novel modeling framework for aquatic systems that integrates spatially-explicit, individual-based, demographic and genetic (demogenetic) assessments with environmental variables. To show its potential utility, we simulated a hypothetical network of 19 migratory riverine populations (e.g., salmonids) using a riverscape connectivity and demogenetic model (CDFISH). We assessed how stream resistance to movement -- a function of water temperature, fluvial distance, and...
Effective wildlife conservation strategies require an understanding of how fluctuating environmental conditions affect sensitive life stages. As part of a long-term study, we examined post-fledging and post-independence survival of 89 radio-marked juvenile Northern Goshawks (Accipiter gentilis) produced from 48 nests in northern Arizona, USA, during 1998-2001. Information-theoretic methods were used to examine within- and among-year variation in survival relative to environmental (prey abundance, weather), territory (hatching date, brood size), and individual (gender, body mass) sources of variation. The results support age- and cohort-specific differences in survival that were best explained by behaviors occurring...
Multiple factors likely influence natal dispersal behavior of juvenile mammals, which is typically male-biased. Because of their small body size and specific habitat requirements, pygmy rabbits (Brachylagus idahoensis) are expected to exhibit limited dispersal. We predicted that dispersal would be male-biased, that juveniles born later in the year would disperse farther, and that juveniles would be more likely to disperse away from areas of higher habitat saturation. We used radiotelemetry to study dispersal of 61 juvenile pygmy rabbits (31 males and 30 females) from shortly after emergence from natal burrows (April?July) to the beginning of the next breeding season (mid-March) during 2004?2006. Juveniles dispersed...
In this paper, we develop a five-step approach for analysis of historical relationships among areas of endemism using a set of 22 clades (9 mammal, 7 bird, 4 reptile, 1 amphibian, and 1 cactus) drawn from the warm deserts biota of western North America. As has been suggested in previous studies of portions of this biota, our results suggest a complex biogeographic history, but with substantial support for the influence of several major vicariant events in the diversification and assembly of the aridlands biota. We discuss and demonstrate the reciprocal strengths (and weaknesses) of phylogeography and phylogenetic biogeography for defining areas of endemism, analysing vicariance and dispersal, and dealing with temporal...
A small numbers of Ospreys (Pandion haliaetus) are known to have nested historically in Utah. A precise baseline figure is unavailable, but the 19th-century Osprey population in Utah probably consisted of at least 15 breeding pairs scattered in 4 geographic regions. Human persecution is believed to have caused the abandonment of nesting territories along the Wasatch Front and in the western Uinta Mountains by 1900 and 1960, respectively. Osprey populations in the southern plateaus and Green River areas, however, began increasing in the late 1970s. Several recent nesting attempts and numerous summer sightings at nontraditional and abandoned historical sites in Utah suggest the Osprey is also expanding its range in...
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Dispersal, establishment, and spread of aquatic invasive species such as the zebra mussel (Dreissena polymorpha) can be influenced by riverine velocities and volumetric flows in invaded lake-stream ecosystems. Zebra mussels, which have a planktonic larval form (veliger), disperse rapidly downstream from a source population. Concentrations, dispersal, and body conditions of zebra mussel veligers were studied under different volumetric flow, or discharge, conditions in a coupled lake-stream ecosystem in northern Texas, USA. Veliger densities in lotic environments were strongly related to population dynamics in upstream lentic source populations. A strong exponential decrease in veliger density was observed through...
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The role of lynx dispersal in maintaining their populations at the landscape scale is unclear. A large proportion of local lynx populations are known to disperse following a snowshoe hare population crash, but whether these dispersal events contribute to the cyclic dynamics of neighboring populations is not well understood. If lynx dispersal does play an important role in lynx population dynamics then the conservation of dispersal corridors is critical to maintaining those dynamics. However, we currently have no information on the habitat requirements of dispersing lynx in relation to human land use, such as housing developments, road building, timber harvest, and mining, all of which could have a substantial impact...
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Ephemeral aquatic habitats in Wupatki National Monument vary from naturally formed pools in arroyos over 5000 years old, to constructed catchment basins with ages estimated at 60?1000+ years old, and borrow pits and stock ponds 30?60 years old. The different ages of these pools provide different histories of colonization by amphibians and aquatic invertebrates, especially temporary pool specialists such as spadefoot toads and branchiopod crustaceans. Ten pools of five different origins and ages were surveyed in August and/or September 1997 for aquatic organisms; a total of 13 surveys were conducted. Twenty-two taxa were found, with the number of species in a pool during any survey ranging from one to 10. Species...
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These data are species distribution information assembled for assessing the impacts of land-use barriers, facilitative interactions with other species, and loss of long-distance animal dispersal on predicted species range patterns for four common species in pinyon-juniper woodlands in the western United States. The layers in the data release are initial distribution records of two kinds: point occurrence records and a raster layer for the general vegetation types where the species is a co-dominant, compiled from other sources. Both types of data are the baseline information in species distribution models for the associated publication.
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The North Pacific Forest Landscape Corridor and Connectivity Project utilized a landscape connectivity simulator (UNICOR) and a genetic simulation program (CDPOP) to model the functional (dispersal and genetic) connectivity in the North Pacific Landscape. The outputs from these programs indicated areas with high potential for landscape and genetic isolation and low probability of dispersal and colonization. In addition, this project was designed to provide spatially-explicit predictions of current and potential future patterns of fragmentation, prioritization of keystone corridors for protection and enhancement, and identification of places that may require habitat restoration or assisted migration to maintain viability....
Categories: Data, Project; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service, Shapefile; Tags: 2011, AK, AK, AK, AK, All tags...
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521 unique elk were monitored across several years with GPS collars in the Greater Yellowstone Ecosystem to determine winter-to-winter annual dispersal distances. There were a total of 704 annual movements. The dataset spans from 2001 to 2015. Annual movements were based on a single location in January or February and another location in the subsequent winter. An individual elk was included at most three times (once for each year) in the data. All elk were female, except one of the individuals in the dataset was a male. We included his movement in the analysis for completeness, but as there was only one male we chose not to directly model any differences in movement behavior between male and female elk.
map background search result map search result map Survey of aquatic macroinvertebrates and amphibians at Wupatki National Monument, Arizona, USA: An evaluation of selected factors affecting species richness in ephemeral pools North Pacific Forest Landscape Corridor and Connectivity Project: Assessing Landscape and Species Vulnerability The matrix matters: effective isolation in fragmented landscapes. Biological and physical data for zebra mussel (Dreissena polymorpha) veligers collected from a coupled lake-stream ecosystem in north Texas, 2012-2014 Occurrence records and vegetation type data used for species distribution models in the western United States Annual winter elk movements in the Greater Yellowstone Ecosystem 2001-2015 Population genetic analysis of three aquatic macroinvertebrate species from samples in Grand Canyon (Arizona, USA) tributaries and nearby reference streams, 2016-2021 Movement Patterns, Dispersal Behavior, and Survival of Lynx in Relation to Snowshoe Hare Abundance in the Boreal Forest The matrix matters: effective isolation in fragmented landscapes. Biological and physical data for zebra mussel (Dreissena polymorpha) veligers collected from a coupled lake-stream ecosystem in north Texas, 2012-2014 Annual winter elk movements in the Greater Yellowstone Ecosystem 2001-2015 Population genetic analysis of three aquatic macroinvertebrate species from samples in Grand Canyon (Arizona, USA) tributaries and nearby reference streams, 2016-2021 Movement Patterns, Dispersal Behavior, and Survival of Lynx in Relation to Snowshoe Hare Abundance in the Boreal Forest Occurrence records and vegetation type data used for species distribution models in the western United States North Pacific Forest Landscape Corridor and Connectivity Project: Assessing Landscape and Species Vulnerability