Fish otolith and water chemistry were assessed in the Grand Canyon reach of the Colorado River and its tributaries. Aqueous strontium and selenium (in ratio to calcium) and carbon stable isotopic ratios were identified as markers with excellent potential to track the provenance and movements of the endangered humpback chub Gila cypha. Although otolith dC and Sr/Ca varied proportionately to wate...

abstract a mountain glacier, when it occupies a river valley, immediately begins to change the cross-section and profile of that valley. river valleys in mountain areas tends to have v-shaped profiles. glaciers work to widen as well as deepen their valleys and the typical cross-section of a glacial valley is u-shaped. the u-shaped glacial valley is one of the most characteristic of glacial land...

Phylogeographic relationships, the timing of clade diversification, and the potential for cryptic diversity in the Slender Madtom, Noturus exilis, was investigated using mitochondrial Cyt b, nuclear RAG2, shape analysis, and meristic and pigmentation data. Three well-supported and deeply divergent clades were recovered from analyses of genetic data: Little Red River (White River drainage) clade...

First posted June 30, 2023 For additional information, contact: Director,Arizona Water Science CenterU.S. Geological Survey520 N. Park AvenueTucson, AZ 85719 The Little Colorado River alluvial aquifer near Leupp, Arizona, was investigated as a possible source of irrigation water for the Leupp and Birdsprings Chapters Navajo Nation. physical, chemical, hydraulic characteristics were studied usin...

in prehistoric studies of iran, the abharrood river basin, located on the east of zanjan province and in the northwestborder of the central plateau, is one of the little-known and dark regions. studying this region according to itsenvironmental features and geographical location is important for understanding regional relations and interregionalinteractions between three cultural-geographical a...

We evaluate the putative introduction of the yellowfin shiner, Notropis lutipinnis, in the Little Tennessee river basin. This species has only been noted in the Little Tennessee in the past several decades and appears to be expanding its range, even though there have been many potential historical pathways for dispersal from native drainages in Georgia, South Carolina, and North Carolina. We us...