Publications
USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.
Filter Total Items: 3111
Testing assumptions for unbiased estimation of survival of radiomarked harlequin ducks Testing assumptions for unbiased estimation of survival of radiomarked harlequin ducks
Unbiased estimates of survival based on individuals outfitted with radiotransmitters require meeting the assumptions that radios do not affect survival, and animals for which the radio signal is lost have the same survival probability as those for which fate is known. In most survival studies, researchers have made these assumptions without testing their validity. We tested these...
Authors
Daniel Esler, Daniel M. Mulcahy, Robert L. Jarvis
Age-specific breeding in Emperor Geese Age-specific breeding in Emperor Geese
I studied the frequency with which Emperor Geese (Chen canagica) of known age were observed breeding on the Yukon-Kuskokwim Delta, Alaska. No one- or two-year old geese were observed on nests. Three-year old geese bred at a lower rate than four-year old geese. These data suggest that patterns of age-specific breeding in Emperor Geese are similar to other sympatrically nesting, large...
Authors
Joel A. Schmutz
Molecular analysis of population genetic structure and recolonization of rainbow trout following the Cantara spill Molecular analysis of population genetic structure and recolonization of rainbow trout following the Cantara spill
Mitochondrial DNA (mtDNA) sequence and allelic frequency data for 12 microsatellite loci were used to analyze population genetic structure and recolonization by rainbow trout, Oncorhynchus mykiss, following the 1991 Cantara spill on the upper Sacramento River, California. Genetic analyses were performed on 1,016 wild rainbow trout collected between 1993 and 1996 from the mainstem and in...
Authors
J.L. Nielsen, Erika L. Heine, Christina A. Gan, Monique C. Fountain
Performance of implantable satellite transmitters in diving seabirds Performance of implantable satellite transmitters in diving seabirds
We report on the first deployment of satellite transmitters in large alcids. In 1995 and 1996, we surgically implanted 51 transmitters in Common and Thick-billed murres (Uria aalge and U. lomvia) and Tufted Puffins (Fratercula cirrhata) at three colonies in Alaska. These devices furnished more than 2,900 locations over succeeding months (eight months maximum transmitter life), some 30-40...
Authors
Scott A. Hatch, P.M. Meyers, D.M. Mulcahy, David C. Douglas
Orphan caribou, Rangifer tarandus, calves: A re-evaluation of overwinter survival data Orphan caribou, Rangifer tarandus, calves: A re-evaluation of overwinter survival data
Low sample size and high variation within populations reduce power of statistical tests. These aspects of statistical power appear to have affected an analysis comparing overwinter survival rates of non-orphan and orphan Caribou (Rangifer tarandus) calves by an earlier study for the Porcupine Caribou Herd. A re-evaluation of the data revealed that conclusions about a lack of significant...
Authors
Kyle Joly
Sexing adult black-legged kittiwakes by DNA, behavior, and morphology Sexing adult black-legged kittiwakes by DNA, behavior, and morphology
We sexed adult Black-legged Kittiwakes (Rissa tridactyla) using DNA-based genetic techniques, behavior and morphology and compared results from these techniques. Genetic and morphology data were collected on 605 breeding kittiwakes and sex-specific behaviors were recorded for a sub-sample of 285 of these individuals. We compared sex classification based on both genetic and behavioral...
Authors
P.G.R. Jodice, Richard B. Lanctot, V.A. Gill, D.D. Roby, Scott A. Hatch
Age- and sex-specific mortality and population structure in sea otters Age- and sex-specific mortality and population structure in sea otters
We used 742 beach-cast carcasses to characterize age- and sex-specific sea otter mortality during the winter of 1990-1991 at Bering Island, Russia. We also examined 363 carcasses recovered after the 1989 grounding of the T/V Exxon Valdez, to characterize age and sex composition in the living western Prince William Sound (WPWS) sea otter population. At Bering Island, mortality was male...
Authors
James L. Bodkin, A.M. Burdin, D.A. Ryazanov
Nearshore fish distributions in an Alaskan estuary in relation to stratification, temperature, and salinity Nearshore fish distributions in an Alaskan estuary in relation to stratification, temperature, and salinity
Fish were sampled with beach seines and small-meshed beam trawls in nearshore ( 1 km) and shallow ( 25 m) habitats on the southern coast of Kachemak Bay, Cook Inlet, Alaska, from June to August, 1996-1998. Fish distributions among habitats were analysed for species composition, catch-per-unit-effort (CPUE) and frequency of occurrence. Two oceanographically distinct areas of Kachemak...
Authors
Alisa A. Abookire, John F. Piatt, Martin D. Robards
Predictability of Bristol Bay, Alaska, sockeye salmon returns one to four years in the future Predictability of Bristol Bay, Alaska, sockeye salmon returns one to four years in the future
Historically, forecast error for returns of sockeye salmon Oncorhynchus nerka to Bristol Bay, Alaska, has been large. Using cross-validation forecast error as our criterion, we selected forecast models for each of the nine principal Bristol Bay drainages. Competing forecast models included stock-recruitment relationships, environmental variables, prior returns of siblings, or...
Authors
Milo D. Adkison, R.M. Peterson
The Tintina Gold Belt - A global perspective The Tintina Gold Belt - A global perspective
The so-called Tintina Gold Belt extends for more than 1000 km along the length of the northern North American Cordillera. Middle to Late Cretaceous Au deposits within the belt have various similar characteristics, among which are a spatial and temporal association with magmatism; Bi-W-Te signatures in deposits hosted by granitod stocks and As-Sb signatures where hosted by sedimentary...
Authors
Richard J. Goldfarb, Craig J. R. Hart, Marti L. Miller, Lance D. Miller, G. Lang Farmer, David I. Groves
Geologic map of the Wildcat Lake 7.5' quadrangle, Kitsap and Mason Counties, Washington Geologic map of the Wildcat Lake 7.5' quadrangle, Kitsap and Mason Counties, Washington
The Wildcat Lake quadrangle lies in the forearc of the Cascadia subduction zone, about 20-km east of the Cascadia accretionary complex exposed in the Olympic Mountains (Tabor and Cady, 1978),and about 100-km west of the axis of the Cascades volcanic arc. The quadrangle lies near the middle of the Puget Lowland, which typically has elevations less than 600 feet (183 m), but on Gold...
Authors
Peter J. Haeussler, Kenneth P. Clark