Champotón River is an unknown area within the Mesoamerican hotspot in Southestern México. Reproductive traits and population structure of Astyanax aeneus were analyzed along an environmental gradient of the upper, middle and lower sections of the river, where diverse environmental factors were recorded. For this, nets were cast for 1 h at each site and A. aeneus were collected from all sections...

In Asia, there are two distinct types of chum salmon (Oncorhynchus keta Walbaum). The early-maturing or “summer” chum salmon generally returns to spawn from June through August in streams bordering Kamchatka, the Sea of Okhotsk, the east coast of Sakhalin Island, and the Amur River. Later-maturing or “autumn” chum salmon generally return to spawn from September through November in streams in Ja...

Background: Aras River is the main source of drinking water supply in northwestern provinces of Iran. The present study aimed to determine the concentration of heavy metals in the river on the border between Iran and Armenia. Methods: Three samples were taken from the Aras river water, the river bottom sediments and the root of Phragmites australis. In water sampling, the concentration of Hg, ...

Climate change causes warming of rivers and may increase discharge, particularly during winter. Downstream hydropower plants, fluctuating water temperature flow create dynamic overwintering conditions for juvenile salmonids. We used inSTREAM 7.2-SD to simulate the effects increased (+2 °C) discharge (+10%) on overwinter growth mortality one-summer- two-summer-old Atlantic salmon brown trout in ...

in semi arid area geomorphological impacts of dams are very major. dams, as man- made structures, have major impacts on river hydrology, primarly through in the timing, magnitude, and frequency of low and high flows, ultimately producing a hydrologic regime differing significantly from the pre-impoundment natural flow regime. despite the profiles of dams on river regulation for water resources ...

We describe a new species of the genus Crenicichla Heckel, 1840, from the Ventuari River, a tributary of the Orinoco River in southern Venezuela. Crenicichla zebrina is distinguished from all other species in the genus by its unique coloration pattern, including the combination of a large, dark, vertically oriented, more or less oval-shaped humeral spot, and thin, dark bars, separated by narrow...

—The flannelmouth sucker Catostomus latipinnis is one of the few native fish that persists in the lower Colorado River basin. Little is known about the effects of hypolimnetic releases of cold, swift water from Colorado River dams on flannelmouth sucker populations. We conducted fatigue velocity tests on age-0 flannelmouth suckers in the laboratory to evaluate the effects of water temperature a...

the little zab river in northwestern iran rises from the mountains piranshehr and flows from the northwest to the southeast direction to join iraq from alan passage. the river basin contains a large number of ancient settlements, and its lower area that is close to the zab river has been the most interesting place for people in the neolithic age. an increasing population during chalcolithic age...