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Seabird monitoring is the accumulation of time series data on any aspect of seabird distribution, abundance, demography, or behavior. Typical studies include annual or less frequent measures of numbers or productivity; less commonly, the focus is on marine habitat use, phenology, food habits, or survival. The key requirement is that...

I compared distribution and range of brown bears (Ursus arctos middendorffi) with temporal and spatial distribution of Sitka black-tailed deer (Odocoileus hemionus sitkensis) hunting activity on westside Kodiak Island, Alaska, to examine impacts of deer hunting on bears. Mean number of bears that annually ranged ≤5 km from the coast,...

We studied morphological and mitochondrial DNA (mtDNA) divergence among three populations of Brachyramphus Murrelets: Kittlitz's Murrelets (B. brevirostris), and tree-nesting and ground-nesting Marbled Murrelets (B. marmoratus). We found little morphological divergence in external and skeletal measurements among Marbled Murrelets, but both populations were easily distinguished from Kittlitz's Murrelets. Principal components...

I quantified ovarian rapid follicle growth (RFG) and regression of postovulatory follicles of Northern Pintails (Anas acuta), American Wigeon (A. americana), and Lesser Scaup (Aythya affinis) by a method that accounted for within-day variation in follicle size. Objective methods for identifying onset of RFG also are presented; this is crucial...

We studied Black-legged Kittiwakes (Rissa tridactyla) in an Alaskan colony where movement of young among nests was possible because of moderate terrain and close nest spacing. Thirty-three percent of chicks in a focal group departed their nests prior to fledging, and seven of the vagrant chicks (58%) were adopted by...

Human disturbance of migrating waterfowl concerns managers of wildlife populations and refuges. Human disturbance may reduce food intake through interruption of foraging bouts or by displacement from feeding areas (Madsen 1985, Belanger and Bedard 1989), and it may increase energy expenditure from additional time in flight (Korschgen et al., 1985)....

Accurate age-class determination of waterfowl is necessary for studies addressing age-specific effects (e.g., Serie et al., 1992) and age structure of populations (e.g., Raveling and Heitmeyer 1989). Duck ages can be determined in fall by morphological and color characteristics of tertial and tail feathers (Carney 1992); however, these feathers are...

We estimated the amount of incubation time that first laid Black Brent eggs received before completion of the clutch. First laid eggs received up to 48 hours of incubation before the last egg was laid in Brent clutches. Waterfowl clutches usually hatch within a period of 24 hours, suggesting that...

In his introduction to the 1979 Symposium proceedings entitled “Shorebirds in Marine Environments," Frank Pitelka stressed the need for studies and conservation programs that spanned the western hemisphere (Pitelka 1979). In the 15 years since Pitelka's call to arms, the locations of many important migratory and wintering sites for shorebirds...

Leadership in ecological research on north-temperate-zone seabirds has long been associated with the region of the northeastern Atlantic, which enjoys a tradition of detailed, innovative work spanning several decades. Although the temperate North Pacific is home to several of the same species that figure prominently in the Atlantic and also...

The incidental catch of seabirds in high-seas drift nets was recorded in 1990-1991 by scientific observers on commercial squid and large-mesh fishery vessels operating in the North Pacific Transitional Zone. Twenty-six Synthliboramphus murrelet deaths were recorded in the months of August through December. All but one were from the Korean...

ound,  Alaska,  spilling  approximately  11  million  barrels  of  crude  oil.  Oil  wasdeposited  on  beaches  nearly  700  km  from  the  spill  site  (Galt  and  Payton  1990,Piatt  et  al.  1990),  affecting  thousands  of  hectares  of  sea  otter(Enhydra  lutris)habitat.  Two  of  the  principal  limitations  in  determining  the  initial  effects  of  theExxon  Valdez  oil ...

We examined coexistence at sea among 7 taxa of diving, wing-propelled seabirds (Alcidae) in the genera Aethia, Uria, Cepphus, and Fratercula. Species abundances were measured simultaneously with a suite of environmental factors in the northern Bering Sea, Alaska, USA; data from 260 adjacent and non-adjacent sites occupied by alcids foraging...

Management of tundra swans (Cygnus columbianus) is hampered by a lack of information on their nesting and brood-rearing ecology. We studied tundra swan nesting and brood-rearing ecology on the Arctic National Wildlife Refuge (ANWR), Alaska, 1988-90. Nest success was 58% (n = 31) in 1988, 83% (n = 36) in...

Population levels of emperor geese (Chen canagica) in Alaska in 1993 were about half that estimated in the 1960s. Survival information is necessary for managers to decide how to best enhance recovery of this species to former levels. We calculated seasonal and annual estimates of emperor goose survival from resightings...

Decoy traps and rocket-nets were compared for capturing Northern Pintails (Anas acuta: hereafter pintails) during May 1991 on the Yukon Flats, Alaska. Males were captured at similar rates using both methods (1.38 vs. 1.07 males/trap d, respectively), but baited rocket-nets were more efficient than decoy traps for capturing females (0.52...

The effect of blood sampling on juvenile Buff-breasted Sandpipers (Tryngites subruficollis) was evaluated by comparing movements, mass, and survival of 10 broods (37 chicks) that were bled and eight broods (31 chicks) that were not bled. Blood was sampled from the jugular vein of chicks when they weighed 9.1 ±...

Seward Peninsula (Fig. 1) may be divided into two geologic terranes (Fig. 2) on the basis of stratigraphy, structure, and metamorphic history. The Seward terrane, an area 150 by 150 km in the central and eastern peninsula, is dominated by Precambrian(?) and early Paleozoic blueschist-, greenschist-, and amphibolite-facies schist and...

The source of the data reported here is a compilation of radiometric ages maintained in conjunction with the Alaska Mineral Resource Assessment Program (AMRAP) studies for Alaska. The symbol shape plotted at each location is coded for rock type, whether igneous, metamorphic, or other; the color of the symbol shows...

South-central Alaska is defined as the region bounded by the Kuskokwim Mountains to the northwest, the basins north of the Alaska Range to the north, the Canadian border to the east, and the Chugach Mountains to the south (Fig. 1). This region, hereafter called the study area, includes the Alaska...

The Aleutian arc is the arcuate arrangement of mountain ranges and flanking submerged margins that forms the northern rim of the Pacific Basin from the Kamchatka Peninsula (Russia) eastward more than 3,000 km to Cooke Inlet (Fig. 1). It consists of two very different segments that meet near Unimak Pass:...

1. The stable isotopes of nitrogen (δ15N) and carbon (δ13C) were analysed in 22 species of marine birds from coastal waters of the northeast Pacific Ocean. Analyses confirm that stable nitrogen isotopes can predict seabird trophic positions.2. Based on δ15N analyses, seabird trophic-level inferences generally agree with those of conventional...

Our objective was to determine if the occurrence and abundance of Pacific loons (Gavia pacifica Lawrence) and horned grebes (Podiceps auritus L.) on 123 wetlands of Yukon Flats National Wildlife Refuge in east central Alaska were related to the limnological characteristics of those wetlands. Aquatic bird-wetland...

The dynamics of mitochondrial and multilocus nuclear genotypic frequencies were monitored for 2 yr in experimental populations established with equal numbers of two poeciliid fishes (Gambusia affinis and Gambusia holbrooki) that hybridize naturally in the southeastern United States. In replicated "small-pool" populations (experiment I), 1018 sampled individuals at six time...