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Page 178, results 4426 - 4450

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Not all publications have extents, not all extents are completely accurate
Remote sensing of vegetation and land-cover change in Arctic Tundra Ecosystems
Douglas A. Stow, Allen Hope, David McGuire, David Verbyla, John A. Gamon, Fred Huemmrich, Stan Houston, Charles H. Racine, Matthew Sturm, Ken D. Tape, Larry D. Hinzman, Kenji Yoshikawa, Craig E. Tweedie, Brian Noyle, Cherie Silapaswan, David C. Douglas, Brad Griffith, Gensuo Jia, Howard E. Epstein, Donald A. Walker, Scott Daeschner, Aaron Petersen, Liming Zhou, Ranga B. Myneni
2004, Remote Sensing of Environment (89) 281-308
The objective of this paper is to review research conducted over the past decade on the application of multi-temporal remote sensing for monitoring changes of Arctic tundra lands. Emphasis is placed on results from the National Science Foundation Land–Air–Ice Interactions (LAII) program and on optical remote sensing techniques. Case...
A quantitative approach to identifying predators from nest remains
R. Michael Anthony, J.B. Grand, T.F. Fondell, B.F. Manly
2004, Journal of Field Ornithology (75) 40-48
Nesting success of Dusky Canada Geese (Branta canadensis occidentalis) has declined greatly since a major earthquake affected southern Alaska in 1964. To identify nest predators, we collected predation data at goose nests and photographs of predators at natural nests containing artificial eggs in 1997-2000. To document feeding behavior by nest...
Foraging depths of sea otters and implications to coastal marine communities
James L. Bodkin, George G. Esslinger, Daniel H. Monson
2004, Marine Mammal Science (20) 305-321
We visually observed 1,251 dives, of 14 sea otters instrumented with TDRs in southeast Alaska, and used attribute values from observed dives to classify 180,848 recorded dives as foraging (0.64), or traveling (0.36). Foraging dives were significantly deeper, with longer durations, bottom times, and postdive surface intervals, and greater descent...
Using satellite radiotelemetry data to delineate and manage wildlife populations
Steven C. Amstrup, T. L. McDonald, George M. Durner
2004, Wildlife Society Bulletin (32) 661-679
The greatest promise of radiotelemetry always has been a better understanding of animal movements. Telemetry has helped us know when animals are active, how active they are, how far and how fast they move, the geographic areas they occupy, and whether individuals vary in these traits. Unfortunately, the inability to...
Detecting denning polar bears with Forward-Looking Infrared (FLIR) imagery
Steven C. Amstrup, G. York, T. L. McDonald, R. Nielson, Kristin S. Simac
2004, BioScience (54) 337-344
Polar bears give birth in snow dens in midwinter and remain in dens until early spring. The survival and development of cubs is dependent on a stable environment within the maternal den. To mitigate potential disruption of polar bear denning by existing and proposed petroleum activities, we used forward-looking infrared...
Duration of the Arctic sea ice melt season: Regional and interannual variability, 1979-2001
G. I. Belchansky, David C. Douglas, Nikita G. Platonov
2004, Journal of Climate (17) 67-80
Melt onset dates, freeze onset dates, and melt season duration were estimated over Arctic sea ice, 1979–2001, using passive microwave satellite imagery and surface air temperature data. Sea ice melt duration for the entire Northern Hemisphere varied from a 104-day minimum in 1983 and 1996 to a 124-day maximum in...
Habitat selection by tundra swans on Northern Alaska breeding grounds
Susan L. Earnst, T. Rothe
2004, Waterbirds (27) 224-233
Habitat selection by the Tundra Swan (Cygnus columbianus columbianus) was evaluated on the Colville River Delta prior to oil field development (1982-1989). Tundra Swan territories comprised a lake, used for refuge and foraging, and terrestrial habitats and ponds near the lake's perimeter used for foraging and nesting. Tundra swan sightings...
A comparison of three methods for assessing raptor diet during the breeding season
S.B. Lewis, Mark R. Fuller, K. Titus
2004, Wildlife Society Bulletin (32) 373-385
Video recording of prey deliveries to nests is a new technique for collecting data on raptor diet, but no thorough comparison of results from traditional methods based on collections of prey remains and pellets has been undertaken. We compared data from these 3 methods to determine relative merits of different...
Additions to the avifauna of St Matthew Island, Bering Sea
James A. Johnson, Steven M. Matsuoka, Daniel R. Ruthrauff, Michael A. Litzow, Maksim N. Dementyev
2004, Western Birds (35) 50-52
St. Matthew Island (60°24' N, 172°42' W) is located in the north-central Bering Sea and is renowned for its distinctive Beringian flora and fauna. Because of its central position between the coasts of Russia and Alaska, St. Matthew Island and its nearby satellites, Hall and Pinnacle islands, support a mixture...
Persistent organic pollutants in Alaskan murre (Uria spp.) eggs: Geographical, species, and temporal comparisons
Stacy S. Vander Pol, Paul R. Becker, John R. Kucklick, Rebecca S. Pugh, David G. Roseneau, Kristin S. Simac
2004, Environmental Science & Technology (38) 1305-1312
Concentrations of persistent organic pollutants (POPs) in eggs of common and thick-billed murres (Uria aalge and U. lomvia) from five Alaskan nesting colonies were dominated by 4,4‘-DDE, total polychlorinated biphenyls (ΣPCBs; 46 congeners comprised mainly of PCB congeners 153, 118, 138, 99, and 151), hexachlorobenzene (HCB), β-hexachlorocyclohexane...
Status of sea otter populations in southcentral and southeast Alaska, 2002-2003
James L. Bodkin
Daniela Maldini, Donald Calkins, Shannon Atkinson, Rosa Meehan, editor(s)
2004, Conference Paper, Alaska Sea Otter Research Workshop: Addressing the Decline of the Southwestern Alaska Sea Otter Population
During the years 2002-2004 estimated sea otter population sizes were calculated for Southeast Alaska, Prince William Sound, and the Kenai Peninsula and Cook Inlet regions of Alaska. Aerial surveys were conducted by a single observer from a float-equipped Bellanca Scout fixed-wing aircraft flying at 91 m altitude and 65 mph....
A molecular comparison of Alaskan and North East Atlantic Halicondria panicea (Pallas 1766) (Porifera: Demospongiae)
Dirk Erpenbeck, Anne L. Knowlton, Sandra L. Talbot, Ray C. Highsmith, Rob W.M. van Soest
2004, Conference Paper, Sponge science in the new millennium: Papers contributed to the VI International Sponge Conference, Rapallo, Italy, 29th September - 5th October 2002
The intraspecific relationships between populations of Alaskan Halichondria cf. panicea are the subjects of ongoing research. In this study we compare CO1 sequences of Alaskan Halichondria cf. panicea with North East Atlantic Halichondria panicea and its sister species Halichondria bowerbanki. Alaskan Halichondria cf. panicea form a well-supported sister group to...
Renewed unrest at Mount Spurr Volcano, Alaska
John A. Power
2004, Eos, Transactions, American Geophysical Union (85) 434-434
The Alaska Volcano Observatory (AVO),a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys, has detected unrest at Mount Spurr volcano, located about 125 km west of Anchorage, Alaska, at the northeast end of the Aleutian...
Sustaining salmonid populations: A caring understanding of naturalness of taxa
Jennifer L. Nielsen, Henry A. Regier
E. Eric Knudsen, editor(s)
2004, Conference Paper, Sustainable management of North American fisheries: American Fisheries Society Symposium 43
Species of the family of Salmonidae occur naturally in Northern Hemisphere waters that remain clear and cool to cold in summer. For purposes of reproduction, salmonids generally behaviorally respond to the currents of streams and lakes in recently glaciated areas. For feeding and maturation, many larger species migrate into existing...
Exploitation dynamics of small fish stocks like Arctic cisco
Jennifer L. Nielsen
2004, Conference Paper, Proceedings of a workshop on the variability of Arctic cisco (Qaaktaq) in the Colville River (MMS 2004-033)
Potential impacts to the Arctic cisco population fall into both demographic and behavioral categories. Possible demographic impacts include stock recruitment effects, limited escapement into marine habitats, and variable age-class reproductive success. Potential behavioral impacts involve migratory patterns, variable life histories, and strategies for seasonal feeding. Arctic cisco stocks are highly...
Small boats disturb fish-holding marbled murrelets
Suzann G. Speckman, John F. Piatt, Alan M. Springer
2004, Northwestern Naturalist (85) 32-34
Disturbance of seabirds by people at nesting colonies can reduce reproductive success and alter population demographics (Vermeer and Rankin 1984). In response to disturbance, adult seabirds may increase the incidence of alarm postures and alarm calling (Burger and Gochfeld 1993), increase heart and breathing rates (Culik and others 1990; Wilson...
Introduction [to Issue 3]
Christian E. Zimmerman, Jennifer L. Nielsen
2004, Reviews in Fish Biology and Fisheries (14) 301-303
Artificial propagation of aquatic organisms is increasing globally and currently accounts for approximately 32% of total world fishery production (Vannuccini, 2004). Between 1970 and 2000, aquaculture production of salmonids has grown from less than 200,000 metric tons per year to over 1.5 million metric tons (Tacon, 2003). In 1995, the...
Ecological overview of Kenai Fjords National Park
Page Spencer, Gail V. Irvine
2004, Alaska Park Science (3) 5-11
The major drivers of Kenai Fjords ecosystems are tectonics and climate. In this overview, we describe how these forces have contributed to the shaping of the lands and ecosystems of Kenai Fjords.Physically, the park is comprised of several distinct components, set within a broader ecophysical framework that includes the Kenai...
Recommendations for the use of mist nets for inventory and monitoring of bird populations
C. John Ralph, Erica H. Dunn, Will J. Peach, Colleen M. Handel
C. John Ralph, Erica H. Dunn, editor(s)
2004, Book chapter, Monitoring bird populations using mist nets (Studies in Avian Biology no. 29)
We provide recommendations on the best practices for mist netting for the purposes of monitoring population parameters such as abundance and demography. Studies should be carefully thought out before nets are set up, to ensure that sampling design and estimated sample size will allow study objectives to be met. Station...
Spatial variation in shorebird nest success: Implications for inference
Brian J. McCaffery, Daniel R. Ruthrauff
2004, Wader Study Group Bulletin (103) 67-70
Estimates of nest success are widely applied in order to evaluate a multitude of theoretical and practical issues. Frequently, however, researchers fail to limit their inferences to the appropriate spatial scale. We evaluated small-scale variation in nest success of Western Sandpipers Calidris mauri during a four-year study on the Yukon-Kuskokwim...
Subarctic, alpine nesting by Bairds Sandpipers Calidris bairdii
Robert E. Gill Jr., Pavel S. Tomkovich
2004, Wader Study Group Bulletin (104) 39-50
Baird's Sandpipers Calidris bairdii were found nesting in alpine habitat in southwestern Alaska (60°48'N, 154°00'W), almost 250 km from the nearest known breeding site, and studied over three consecutive seasons, 1997-1999. The first birds arrived during the second week of May each spring with peak numbers recorded the third week...
Response of predators to Western Sandpiper nest exclosures
Amanda C. Niehaus, Daniel R. Ruthrauff, Brian J. McCaffery
2004, Waterbirds (27) 79-82
In 2001, predator exclosures were used to protect nests of the Western Sandpiper (Calidris mauri) in western Alaska. During the exclosure experiment, nest contents in exclosures had significantly higher daily survival rates than control nests, however, late in the study predators began to cue in on exclosures and predate the...
Sea otter research methods and tools
James L. Bodkin
Daniela Maldini, Donald Calkins, Shannon Atkinson, Rosa Meehan, editor(s)
2004, Conference Paper, Alaska Sea Otter Research Workshop: Addressing the Decline of the Southwestern Alaska Sea Otter Population
Sea otters possess physical characteristics and life history attributes that provide both opportunity and constraint to their study. Because of their relatively limited diving ability they occur in nearshore marine habitats that are usually viewable from shore, allowing direct observation of most behaviors. Because sea otters live nearshore and forage...