A hydrologic modeling data set is presented for water years 2006 through 2012 from the Senator Beck Basin (SBB) study area. SBB is a high altitude, 291 ha catchment in southwest Colorado exhibiting a continental, radiation-driven, alpine snow climate. Elevations range from 3362 m at the SBB pour point to 4118 m. Two study plots provide hourly forcing data including precipitation, wind speed, air temperature and humidity, global solar radiation, downwelling thermal radiation, and pressure. Validation data include snow depth, reflected solar radiation, snow surface infrared temperature, soil moisture, temperatures and heat flux, and stream discharge. Snow water equivalence and other snowpack properties are captured in snowpack profiles. An example of snow cover model testing using SBB data is discussed. Serially complete data sets are published including both measured data as well as alternative, corrected data and, in conjunction with validation data, expand the physiographic scope of published mountain system hydrologic data sets in support of advancements in snow hydrology modeling and understanding.

Impoundment effects override natural, reach‐based channel geomorphology influences on seasonal waterbird distribution in Grand Canyon along the Colorado River downstream from Glen Canyon Dam. Large winter waterbird populations were rare or non‐existent prior to completion of Glen Canyon Dam in 1963, and pre‐dam summer breeding was rare. Post‐dam river corridor surveys of 13 geomorphological reaches from 1973 to 1994 detected 58 species of waterfowl, waders, shorebirds and piscivorous raptors, with a grand mean of 138·2 waterbirds/reach (SE=31·0, n=727 reach surveys), and a mean area‐adjusted rate of encounter (AARE) of 372·8 waterbirds km−1 h−1 of observation per reach (SE=69·1). The post‐dam assemblage has been dominated by Anseriformes (13 diving and 12 dabbling species) and includes regionally significant populations of wintering waterfowl and bald eagle, and breeding mallard. Most wading birds and shorebirds occur primarily as migrants or summer vagrants. Total waterbird AARE was greatest in the productive clear water (CW) and variably turbid (VT) segments upstream from the Little Colorado River (LCR) (km 98), decreasing downstream on the usually turbid (UT) lower Grand Canyon segment. Mean total winter waterfowl AARE was 1076·8, and decreased by three orders of magnitude from the CW to the UT segments (p=0·0001). Mean total summer AARE was 2·7, and also decreased across the turbidity segments (p=0·066). In contrast, AARE varied little between wide and narrow geomorphological reaches. Total AARE was only 1·4 and 1·3‐fold greater in wide versus narrow reaches within the VT and UT turbidity segments, respectively (p<0·0002). Winter AARE was threefold greater (p=0·0002), while summer AARE was equivalent between wide and narrow reaches. These tributary‐related turbidity and geomorphological reach width factors contributed to a non‐linear, circuitous shift in the waterbird assemblage over distance downstream from the dam, differentially affecting the seasonal distribution of waterbird feeding guilds. We discuss flow regulation and habitat management implications. © 1997 John Wiley & Sons, Ltd.