Reports

A group of thunderstorms produced >4 in of rain during four periods of progressively more intense rainfall across a small part of a relatively high-elevation area of the northern Black Hills on 5 August 2014. The resulting hydrologic response was noteworthy in two very small headwater drainage basins, where the measured peak flows are by far the largest—relative to drainage area—ever...

We found that average cytochrome P4501A induction (as measured by EROD activity) during March 2014 was not elevated in wintering harlequin ducks captured in areas of Prince William Sound oiled by the 1989 Exxon Valdez oil spill, relative to those captured in unoiled areas. This result is consistent with findings from March 2013. We interpret these findings to indicate that exposure of...

Ground-motions for the PEER NGA-East project were simulated using a point-source stochastic method. The simulated motions are provided for distances between of 0 and 1200 km, M from 4 to 8, and 25 ground-motion intensity measures: peak ground velocity (PGV), peak ground acceleration (PGA), and 5%-damped pseudoabsolute response spectral acceleration (PSA) for 23 periods ranging from 0.01...

Numerous geochemical and geophysical studies have been conducted at Yellowstone National Park to better understand the hydrogeologic processes supporting the thermal features of the Park. This report provides the first 87Sr/86Sr and 234U/238U data for thermal water from the Upper Geyser Basin (UGB) intended to evaluate whether heavy radiogenic isotopes might provide insight to sources of

Knowledge of the capacity and flow of ecosystem services can help DoD land managers make decisions that enhance cost-effectiveness, minimize environmental damage, and maximize resources available for military missions. We demonstrated a methodology to quantify and map selected regulating services (RS), which helps land managers envision tradeoffs. Our objectives were to 1) estimate...

The clapper rail (Rallus longirostris) recently was split into two sister groups (Chesser et al. 2014) on the basis of phylogenetic analyses (Maley and Brumfield 2013). The original grouping is now represented on the East Coast of North America by the Clapper rail (Rallus crepitans) and on the West Coast by the Ridgway’s rail (Rallus obsoletus). The California Ridgeway’s rail (Rallus...

Dabbling ducks are the most abundant group of waterfowl that overwinter in the shallow wetlands and ponds of San Francisco Bay (SFB). Species within this group are primarily omnivorous, feeding on both plant material and macroinvertebrate prey by “tipping” to access benthic foods in bottom sediments or by foraging in the water column. Although the majority of these ducks are migratory...

Diving ducks are the most abundant group of waterfowl that overwinter in the open bays and ponds of San Francisco Bay (SFB). Species within this group are primarily benthivores that dive to obtain their macroinvertebrate prey in bottom sediments, although at times they may eat plant matter or forage in the water column. These migratory species include bay ducks (lesser scaup Aythya...

This case study considers two tern species that breed within the San Francisco Bay Estuary, Forster’s Terns (Sterna forsteri) and California Least Terns (Sternula antillarum browni). Forster’s Terns are medium-sized (140 g) terns that breed in coastal and interior marshes of North America. Forster’s Terns can exploit ephemeral habitats, and colony locations often move among years with...

This case study includes representative macroinvertebrates that live in the marsh plain, its associated channels and pannes (ponds), and the marsh-upland transition zone. While less visible than animals such as birds, invertebrates play important roles in physical and biological processes (e.g., burrowing activity and channel bank erosion, and detritivores breaking down organic matter)...

Western sandpipers (Calidris mauri) are small (22-35 g) sexually dimorphic sandpipers, with males typically smaller than females. Western sandpipers frequently occur in mixed species flocks along with other Calidris species, including least sandpipers (Calidris minutilla) and dunlin (Calidris alpina), in the San Francisco Bay Estuary (SFBE) and are the most abundant shorebird species...

Scientifically defensible predictions of field scale U(VI) transport in groundwater requires an understanding of key processes at multiple scales. These scales range from smaller than the sediment grain scale (less than 10 μm) to as large as the field scale which can extend over several kilometers. The key processes that need to be considered include both geochemical reactions in...