scholarly journals Distribution, habitat associations, and conservation status updates for the pilose crayfish Pacifastacus gambelii (Girard, 1852) and Snake River pilose crayfish Pacifastacus connectens (Faxon, 1914) of the western United States

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5668 ◽  
Author(s):  
Rachel M. Egly ◽  
Eric R. Larson
Keyword(s):  
United States ◽  
Classification Tree ◽  
Conservation Status ◽  
False Positives ◽  
Habitat Associations ◽  
Boosted Regression Trees ◽  
Western United States ◽  
Snake River ◽  
Precipitation Seasonality ◽  
Historical Sites

Our study evaluates the distribution, habitat associations, and current conservation status of the Snake River pilose crayfish Pacifastacus connectens (Faxon, 1914) and pilose crayfish Pacifastacus gambelii (Girard, 1852), two little-studied and data-deficient species endemic to the western United States. We first developed a species distribution model (SDM) for the pilose crayfishes based on their historical occurrence records using boosted regression trees and freshwater GIS data layers. We then sampled 163 sites in the summers of 2016 and 2017 within the distribution of these crayfishes, including 50 where these species were observed historically. We next compared our field results to modeled predictions of suitable habitat from the SDM. Our SDM predicted 73 sites (45%) we sampled as suitable for the pilose crayfishes, with a moderate AUC value of 0.824. The pilose crayfishes were generally predicted to occur in larger streams and rivers with less extreme upstream temperature and precipitation seasonality. We found the pilose crayfishes at only 20 (12%) of the 163 total sites we sampled, 14 (20%) of the 73 sites predicted as suitable for them by our SDM, and 12 (24%) of 50 historical sites that we sampled. We found the invasive virile crayfish Faxonius virilis (Hagen, 1870) at 22 sites total and 12 (24%) historical sites for the pilose crayfishes, and we found the “native invader” signal crayfish Pacifastacus leniusculus (Dana, 1852) at 29 sites total and 6 (12%) historical sites for the pilose crayfishes. We subsequently used a single classification tree to identify factors associated with our high rate of false positives for contemporary pilose crayfish distributions relative to our SDM. This classification tree identified the presence of invasive crayfishes, impairment of the benthic community, and sampling method as some of the factors differentiating false positives relative to true positives for the pilose crayfishes. Our study identified the historical distribution and habitat associations for P. connectens and P. gambelii using an SDM and contrasted this prediction to results of contemporary field sampling. We found that the pilose crayfishes have seemingly experienced substantial range declines, attributable to apparent displacement by invasive crayfishes and impairment or change to stream communities and habitat. We recommend increased conservation and management attention to P. connectens and P. gambelii in response to these findings.

scholarly journals Distribution, habitat associations, and conservation status updates for the pilose crayfish Pacifastacus gambelii and Snake River pilose crayfish Pacifastacus connectens of the western United States

2018 ◽  
Author(s):  
Rachel M Egly ◽  
Eric R Larson
Keyword(s):  
United States ◽  
Classification Tree ◽  
Conservation Status ◽  
False Positives ◽  
Habitat Associations ◽  
Boosted Regression Trees ◽  
Western United States ◽  
Suitable Habitat ◽  
Precipitation Seasonality ◽  
Historical Sites

Our study evaluates the distribution, habitat associations, and current conservation status of the pilose crayfishes Pacifastacus connectens and Pacifastacus gambelii, two little-studied and data-deficient species endemic to the western United States. We first developed a species distribution model (SDM) for the pilose crayfishes based on their historical occurrence records using boosted regression trees and freshwater GIS data layers. We then sampled 163 sites in the summers of 2016 and 2017 within the distribution of these crayfishes, including 50 where these species were observed historically. We next compared our field results to modeled predictions of suitable habitat from the SDM. Our SDM predicted 73 sites (45%) we sampled as suitable for the pilose crayfishes, with a moderate AUC value of 0.824. The pilose crayfishes were generally predicted to occur in larger streams and rivers with less extreme upstream temperature and precipitation seasonality. We found the pilose crayfishes at only 20 (12%) of the 163 total sites we sampled, 14 (20%) of the 73 sites predicted as suitable for them by our SDM, and 12 (24%) of 50 historical sites that we sampled. We found the invasive virile crayfish Faxonius virilis at 22 sites total and 12 (24%) historical sites for the pilose crayfishes, and the “native invader” signal crayfish Pacifastacus leniusculus at 29 sites total and 6 (12%) historical locations. We subsequently used a single classification tree to identify factors associated with our high rate of false positives for contemporary pilose crayfish distributions relative to our SDM. This classification tree identified the presence of invasive crayfishes, impairment of the benthic community, and sampling method as some of the factors differentiating false positives relative to true positives for the pilose crayfishes. Our study identified the historical distribution and habitat associations for P. connectens and P. gambelii using an SDM and contrasted this prediction to results of contemporary field sampling. We found that the pilose crayfishes have seemingly experienced substantial range declines, attributable to apparent displacement by invasive crayfishes and impairment or change to stream communities and habitat. We recommend increased conservation and management attention to P. connectens and P. gambelii in response to these findings.

scholarly journals Distribution, habitat associations, and conservation status updates for the pilose crayfish Pacifastacus gambelii and Snake River pilose crayfish Pacifastacus connectens of the western United States

2018 ◽  
Author(s):  
Rachel M Egly ◽  
Eric R Larson
Keyword(s):  
United States ◽  
Classification Tree ◽  
Conservation Status ◽  
False Positives ◽  
Habitat Associations ◽  
Boosted Regression Trees ◽  
Western United States ◽  
Suitable Habitat ◽  
Precipitation Seasonality ◽  
Historical Sites

Our study evaluates the distribution, habitat associations, and current conservation status of the pilose crayfishes Pacifastacus connectens and Pacifastacus gambelii, two little-studied and data-deficient species endemic to the western United States. We first developed a species distribution model (SDM) for the pilose crayfishes based on their historical occurrence records using boosted regression trees and freshwater GIS data layers. We then sampled 163 sites in the summers of 2016 and 2017 within the distribution of these crayfishes, including 50 where these species were observed historically. We next compared our field results to modeled predictions of suitable habitat from the SDM. Our SDM predicted 73 sites (45%) we sampled as suitable for the pilose crayfishes, with a moderate AUC value of 0.824. The pilose crayfishes were generally predicted to occur in larger streams and rivers with less extreme upstream temperature and precipitation seasonality. We found the pilose crayfishes at only 20 (12%) of the 163 total sites we sampled, 14 (20%) of the 73 sites predicted as suitable for them by our SDM, and 12 (24%) of 50 historical sites that we sampled. We found the invasive virile crayfish Faxonius virilis at 22 sites total and 12 (24%) historical sites for the pilose crayfishes, and the “native invader” signal crayfish Pacifastacus leniusculus at 29 sites total and 6 (12%) historical locations. We subsequently used a single classification tree to identify factors associated with our high rate of false positives for contemporary pilose crayfish distributions relative to our SDM. This classification tree identified the presence of invasive crayfishes, impairment of the benthic community, and sampling method as some of the factors differentiating false positives relative to true positives for the pilose crayfishes. Our study identified the historical distribution and habitat associations for P. connectens and P. gambelii using an SDM and contrasted this prediction to results of contemporary field sampling. We found that the pilose crayfishes have seemingly experienced substantial range declines, attributable to apparent displacement by invasive crayfishes and impairment or change to stream communities and habitat. We recommend increased conservation and management attention to P. connectens and P. gambelii in response to these findings.

Writing Time in Metaphors

2018 ◽  
Author(s):  
Jennifer J. Smith
Keyword(s):  
United States ◽  
The United States ◽  
Western United States ◽  
Entire System ◽  
Language And Culture ◽  
Space Race ◽  
Do So

Coherence of place often exists alongside irregularities in time in cycles, and chapter three turns to cycles linked by temporal markers. Ray Bradbury’s The Martian Chronicles (1950) follows a linear chronology and describes the exploration, conquest, and repopulation of Mars by humans. Conversely, Louise Erdrich’s Love Medicine (1984) jumps back and forth across time to narrate the lives of interconnected families in the western United States. Bradbury’s cycle invokes a confluence of historical forces—time as value-laden, work as a calling, and travel as necessitating standardized time—and contextualizes them in relation to anxieties about the space race. Erdrich’s cycle invokes broader, oppositional conceptions of time—as recursive and arbitrary and as causal and meaningful—to depict time as implicated in an entire system of measurement that made possible the destruction and exploitation of the Chippewa people. Both volumes understand the United States to be preoccupied with imperialist impulses. Even as they critique such projects, they also point to the tenacity with which individuals encounter these systems, and they do so by creating “interstitial temporalities,” which allow them to navigate time at the crossroads of language and culture.

Women's Studies in the Western United States

NWSA Journal ◽  
2004 ◽  
Vol 16 (2) ◽  
pp. 180-189
Author(s):  
Karen L. Salley ◽  
Barbara Scott Winkler ◽  
Megan Celeen ◽  
Heidi Meck
Keyword(s):  
United States ◽  
Women's Studies ◽  
Western United States ◽  
Women’S Studies

MONUMENTS OF NATURE AND HISTORICAL AND CULTURAL OBJECTS OF THE DNISTROVSKYI RLP: THE STATE OF PROTECTION AND THE PROSPECTS OF TOURIST USE

2020 ◽  
pp. 73-87
Keyword(s):  
Conservation Status ◽  
Educational Value ◽  
Cultural Objects ◽  
Cultural Sites ◽  
New Information ◽  
Geological Features ◽  
Tourist Infrastructure ◽  
Historical Sites ◽  
Surrounding Areas ◽  
Recreational Resources

The existing nature conservation objects that are part of the Dnistrovskyi Regional Landscape Park are characterized and mapped. There are more than sixty different types of WFD objects in and around the park. All objects are tabulated. Also, geological, geomorphological, hydrological objects have been identified that have scientific, recreational and educational value, which gives grounds for granting them conservation status. This is a large number of rocks of different ages (Silurian, Devonian, Jurassic, Cretaceous), which makes it possible to study the history and condition sof the territory. The location is mapped. Also on the map as places of interest are the places of manifestation of modern geomorphological processes. Fluvial, karst, gravity, erosion and other processes are most evidentin the park. The dynamics of karst processes haveled to the formation of numerous caves and cave formations, which are valuable from the scientific and recreational plan. A mong the hydrological and hydro-geological features are waterfalls, marshe sand ground water exits to the surface in the form of springs. Historical and cultural sites occurring with in and around the park are characterized and mapped. The seare objects of Paleolithic heritage (the oldestin Bukivna, Horodnytsia), Kievan Rus' period, ruins of ancient castles (Rakovetsky and Chekrnelitsky) and fotresses, lordlye states, ancient churches, of which there are more than thirty, existing and in active in the region. The most ancient are the village of Michalce), monuments of liberation competitions (hiding places) and places of great historical battles. It maps and describes the existing route sand objects of the tourist infrastructure of the Dnistrovskyi RLP. The park and surrounding areas haves ignificant natural and recreational potential. The presence of a large number of diverse natural sites make sit possible to create attractions for tourism development in the region. The presence of historical and cultural heritage en hances the use of the territory. New routes and proposals for improvement of the tourist infrastructure of the territory were developed: creation of an eco-educational visit center, placement of agroosel complexes, arrangement of places for stops during the Dniester alloys, creation of a network of tourist points at the places of passage of route sand places of rest of residents, development and in stallation of new information standsne are xisting tourist natural and historical sites in the study area. Key words: Dnistrovskyi RLR, Nature Reserve objects, historical and cultural sites, nature monuments, recreational resources, tourism.

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