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  Relationships between deer and vegetation on Coronation Island, southeastern Alaska

  Lewis, Stephen Woods; Klein, David R.; Bowyer, R. Terry; Hanley, Thomas A.; White, Robert G. (1992-05)

  Relationships between Sitka black-tailed deer (Odocoileus hemionus sitkensis) and their forage were assessed on Coronation Island in southeastern Alaska. I compared plant abundance, species richness, and deer body size with results from an earlier study by Klein (1965, Ecol. Monogr. 35:259-284). Wolves were introduced, flourished, and then died out between these studies. The deer population rebounded after the wolf-induced low. Deer were significantly larger and plants more abundant and speciose in my study. Forbs, graminoids, and shrubs predominated in summer deer feces, similar to other sites in southeastern Alaska, whereas conifers composed 73% of winter feces; a much greater percentage of conifers than in feces from other sites. Estimated metabolizable energy in all summer diets was sufficient for maintenance and reproduction. Winter diet on Coronation provided less than half the energy believed necessary for maintenance. Different intensities of use of vegetation by deer appear responsible for these differences.
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  A southeastern Alaska mink management study

  Croxton, Loren W. (1960-05)

  Mink management in coastal southeastern Alaska was studied from June 1, 1959, to January, 1960. Mink summer along rivers and streams and in upland muskegs, but they winter in a narrow beach zone. Present trapping removes more than the harvestable surplus with trapping on a yearly basis but not if it is restricted to alternate years. Optimum harvest can be sustained on a yearly basis if only the surplus is taken. Illegal trapping is widespread. A few mink were caught and tagged; live-trap mortality was nearly eliminated with an all-wood protective trap. Full pelt primeness was reached by December 10 and extended to mid-january. Recommendations include December 10 to January 10 trapping seasons in alternate years only, registered trap lines, and sealing of pelts.
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  Spawning stocks and juvenile summer habitat of rainbow trout and steelhead, Gulkana River, Alaska

  Stark, Thomas Christopher (1999-05)

  The Gulkana River supports the northernmost population of steelhead and rainbow trout Oncorhynchus mykiss in North America. The summer habitat of Gulkana River juvenile trout (i.e., steelhead and rainbow trout) was identified and described. Analysis of geomorphological features of stream reaches (stream entrenchment, bankfull width-to-depth ratio, sinuosity, channel material, and slope) in relation to differential use of habitat by juvenile trout indicated a strong preference for type C reaches (predominately riffle/run habitat) over type E reaches (predominately slow run habitat). A comparison of micro-habitats (riffle, run, pool, slow run) within those same reaches and distribution of juvenile trout indicated a preference for riffle and run habitat. Most type C reaches in the Mainstem were sparsely populated by juveniles throughout summer. The Middle Fork was devoid of juveniles in early summer. In mid- and late summer, coinciding with the arrival of spawning chinook O. tshawytscha and sockeye salmon O. nerka, most riffle/run reaches in the Middle Fork were occupied by juvenile trout. The steelhead spawning population has declined from an estimated 200-1,000 fish two decades ago to 20-50 fish during this study (1993-1995). Rainbow trout stocks are also apparently low. Monitoring of Copper River fisheries and Gulkana spawning populations and an investigation into other steelhead spawning populations in the Copper River basin are recommended
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  Lake productivity indices as estimators of carrying capacity for burbot and northern pike in Interior Alaska

  Simpson, Thomas David (1998-12)

  Two Alaska sport fish species, burbot and northern pike, were used to test the ability to estimate carrying capacity of fishes based on biotic and abiotic indices of lake productivity. Understanding the quantitative relationships between the potential fish productivity of freshwater lakes and physical, biological, or chemical characteristics could provide models sufficient for calculating a timely prediction of carrying capacity to evaluate the population status. This would provide a technique for allocating limited resources for fishery stock assessment as an aide in resource management of sport fisheries. The lakes covered in the study lie in an area spanning West 151°--142°/North 64°30ʹ--61°52ʹ. They are Fielding Lake, George Lake, Glacier Lake, Harding Lake, Hudson Lake, Jatahmund Lake, Lake Louise, Landlocked Tangle Lake, Moose Lake, Paxson Lake, Sevenmile Lake, T Lake, Tolsona Lake, Volkmar Lake, and West Twin Lake.
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  Seasonal habitat relationships of adult female deer on Kodiak Island, Alaska

  Selinger, Jeffrey S. (1995-12)

  Movements of adult female deer (Odocoileus hemionus sitkensis) were monitored using radio-collars (n = 21) in a region lacking old-growth conifer forest on Kodiak Island, Alaska, from 17 July 1990 to 8 July 1991. Mean distance between seasonal ranges for 7 deer that migrated from the study area during winter was 22 km (SD = 10.2 km), whereas < 5 km separated seasonal ranges of 14 deer that remained in the study area throughout the year. Mean movement date to winter range was 30 October (SD = 38 days), and to summer range, 29 May (SD = 18 days). Overall habitat use differed significantly (P < 0.001) between seasons. Habitats used more than available (P ≤ 0.01) were tall shrub closed in summer and tall shrub open in winter. Using the 95% adaptive kernel method (Worton 1989), mean summer home range (454 ha, n = 11, range 134 - 819 ha, SD = 227 ha) was larger (P < 0.001)than the mean winter home range (107 ha, n = 9, range 67-217 ha, SD = 56 ha).
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  Plant architecture and forage selection by moose

  Mallek, Edward Joseph II (1999-08)

  The effects of plant architecture on browse selection and the extent of use of Salix alaxensis and Salix plantifolia by moose foraging in winter in Interior Alaska were studied during 1997 and 1998. Three sampling techniques were employed to estimate forage availability and utilization. Sampling forage availability prior to use (in autumn) provided the best estimates of forage use in spring. In Salix plantifolia, selection of current annual growth (CAG) twigs was significantly related to basal diameter of CAG, diameter of nearest neighbor, distance to nearest neighbor, and number of leaders per cluster. In contrast, CAG selection in Salix alaxensis was related only to basal diameter. The proportion of CAG biomass removed from stems of either species was not related to any measured plant architecture variables. Because plant architecture affects browse use by moose, it is an important factor in determining food availability, and thereby in assessing moose habitat
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  Comparative habitat and diet selection of muskoxen and reindeer on the Seward Peninsula, western Alaska

  Ihl, Claudia (1999-05)

  Factors influencing choice of feeding sites, cratering microsites and diets of reindeer (Rangifer tarandus) and reintroduced muskoxen (Ovibos moschatos) were examined on the Seward Peninsula, western Alaska, during late winters of 1996 and 1997. Both ungulates foraged primarily in upland habitats with low snow depth, relatively high occurrence of lichens and low occurrence of graminoids. Both selected against snow depth when choosing feeding sites and against snow depth and hardness when selecting cratering areas within feeding sites. Diet selection differed between species. Reindeer selected mainly lichens while muskoxen selected more sedge and moss. Few behavioral interactions between species were observed, and none seemed to result in displacement of either species. Despite similar use of late winter feeding sites, competition between muskoxen and reindeer in the study area is not likely at the moment, but may occur if severe snow conditions or increasing densities of either species restrict available winter habitat
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  Estimation of aging accuracy and precision, growth, and sustained yield of coastal cutthroat trout in Southeast Alaska

  Ericksen, Randolph Peder (1997-08)

  This study was designed to validate and estimate accuracy and precision of ages determined from scales sampled from coastal Cutthroat trout Oncorhynchus clarki clarki in Southeast Alaska; to model growth of these fish; and to evaluate the sensitivity of sustained yield estimates to aging error. Cutthroat trout scales sampled in Southeast Alaska did not always form an annulus during the first year, although the number of circuli up to the first apparent annulus was a good indicator that one was missing. Reader error generally resulted in significant underaging of older fish from scales. However, aging error models developed in this study significantly improved the accuracy of ages estimated from scales. Growth of cutthroat trout was best described by a Gompertz growth curve and was significantly different between the populations studied. Underaging of cutthroat trout resulted in underestimates of optimum levels of fishing mortality and yield.
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  Distribution and behavior of barren-ground caribou in relation to weather and parasitic insects

  Dau, Jim (1986-09)

  Relationships between weather and the activity of mosquitoes (Culicidae) and oestrid flies (Oestridae), and responses by caribou (Rangifer tarandus) to insect harassment, were examined near Milne Point, Alaska. Weather conditions were usually unfavorable for insects within 20 km of the Beaufort Sea, and were least favorable within 1-3 km of the eoast. Weather affected the occurrence more than the level of insect activity. Mosquitoes were rarely active within 1 km of the coast; maritime weather conditions had little effect on oestrids. Weather conditions and insect activity were more variable through time than through space： this necessitated models predicting: (1) the presence of insects, and (2) levels of insect activity when insects were present. Insect harassment caused caribou to travel rapidly to coastal areas at the expense of feeding and lying, and form large, mixed groups. Insect activity was most highly correlated with caribou rate of travel and behavior.
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  Differential use of willow species by moose in Alaska

  Machida, Steven (1979)

  Patterns of differential winter utilization of willow by moose in Interior Alaska and the Kenai Peninsula were studied during 1977 and 1978. Knowledge of such patterns is important to the wildlife manager who must evaluate the relative importance of different habitat types for moose. The study areas were composed of sites dominated by mature and seral habitat types.
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  Aquatic habitat of the Tiekel River, southcentral Alaska, and its utilization by resident Dolly Varden (Salvelinus malma)

  Martin, Donald C. (1988-05)

  The Tiekel River is a third order stream in southcentral Alaska and contains stream-resident Dolly Varden (Salvelinus malma) that are small in size. The purpose of this project was to compile baseline aquatic habitat data, determine which habitats were the most important to the Dolly Varden and should be protected from future development, and develop management recommendations. Habitat data suggested that the Tiekel River drainage contained a wide variety of habitats that could fulfill the life requirements for a number of fish species. Habitat suitability index graphs were constructed for the important habitat variables and should be used in the planning of future habitat alterations to assure that habitat quality does not suffer. The beaver ponds were found to have a greater probability of producing large fish than the stream habitats. Fish size was positively correlated with August water temperatures and chlorophyll a concentrations.
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  Growth patterns of juvenile sockeye salmon in different thermal environments of Alaskan lakes

  Edmundson, Jim A. (1997-12)

  Rearing conditions imposed on juvenile salmonids in lakes are important determinants of freshwater growth patterns. In Alaska, sockeye salmon (Oncorhynchus nerka) nursery lakes exhibit a wide range in thermal characteristics. Compared to clear lakes, stained lakes are warmer and have longer growing seasons, whereas glacial lakes are colder and have shorter growing seasons. In stained lakes, a shallow thermocline restricts most of the heat to the surface layers. Deep mixing in glacial lakes, concomitant with meltwater intrusion, keep much of the water column near 4 °C. Mean depth accounts for 77% of the among-lake variation in the seasonal average water temperature (TS). Length of growing season is dependent on latitude and altitude; however, water temperature is not. Taken together, the factors TS, zooplankton biomass, and sockeye fry density accounted for 70% of the variation in age-1 sockeye smolt size. This limnological information can be included in stock-recruit models of sockeye salmon to improve assessments for management.
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  Effects of calcium magnesium acetate on small ponds in interior Alaska

  Rea, Caryn L. (1986-09)

  Deicing winter roads with chlorides has been common practice in northern areas. Corrosion of vehicles, structures, and pavements has resulted in damage, and roadside vegetation and public water supplies have been severely impacted by heavy salt usage. Calcium magnesium acetate (CMA) was identified as a promising alternative to chloride salts. This research focused on the effects on planktonic algae and bacteria in small ponds, to help assess the environmental acceptability of CMA in Alaska. The most serious consequence resulting from CMA was a dissolved oxygen concentration decrease, partly attributable to increased bacteria populations utilizing oxygen during degradation of acetate. Algal biomass recovered toward the end of the summer indicating that the algae may be utilizing some of the carbon dioxide being released by the bacteria. Rapid turnover times of acetate by bacteria in the fall and continued low dissolved oxygen indicated that some of the acetate was being recycled.
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  Seasonal changes in body mass and composition of northern red-backed voles (Clethrionomys rutilus) in interior Alaska

  Zuercher, Gerald Lawrence (1995-12)

  Northern red-backed voles (Clethrionomys rutilus) undergo a pronounced annual cycle in body mass: highest in summer, lowest in winter. I trapped voles throughout 1994 to determine how body composition and relative size of body components contributed to this cycle. Seasonal changes in body mass were primarily due to changes in body water and lean dry matter. Total body fat was low throughout the year, peaking in spring and early summer. Relative ash content was lowest in early summer. Most body components declined in dry mass and percent water during autumn, with skeletomuscular components contributing most to loss of body mass. Most body components declined in proportion to declines in body mass, but a few components declined proportionally greater than or less than body mass. Total Body Electrical Conductivity (TOBEC) of live voles explained 94% of the variation in lean mass and body water, but accuracy of fat estimates was poor.
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  Dynamics of a super-population of dolly varden in the Chiniak Bay system, Kodiak Island, Alaska

  Whalen, Mary E. (1993-05)

  A weir was operated at Buskin Lake, Kodiak Island, Alaska in the spring of 1990, 1991 and 1992 to study the stock structure of a super­population of Dolly Varden (Salvelinus malma) in Chiniak Bay. In 1991, Jolly-Seber estimates of abundance (60,585) and survival (29.3%) were higher than the weir estimates of 30,725 and 6.3%. Growth parameter estimates were 0.23 for the Brody coefficient and 522 mm as the largest fish in the population. Age 4-7 fish dominated the spring emigration from Buskin Lake. Dolly Varden found in the fall at the American and Olds rivers and Buskin Lake constitute the main spawning stocks for the Chiniak Bay super-population at 3,375, 2,669 and 3,711 fish respectively in 1991. A dynamic pool model used in conjunction with Relative Stock Density was effective in detecting increases in length-specific exploitation of larger fish, but not for detecting increasing fishing mortality in the mature stock.
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  Effects of military overflights on habitat use and selection by female Dall's sheep, Yukon-Tanana uplands, Alaska

  Wendling, Bradley R. (2008-12)

  "My objective was to assess the potential effects of military overflights on home range size, movement rates, habitat use, and habitat selection of female Dall's sheep (Ovis dalli) during 2-week sequential periods, April-July, 1999-2002. I examined sheep in 2 study areas overlain with designated military training airspace within the Yukon-Tanana uplands, Alaska. I examined the effects of study area, year, and sequential time period on: 1) mean home range size, 2) mean minimum hourly distance traveled by sheep, and 3) mean use and selection ratios for the habitat variables of elevation, slope, terrain ruggedness, aspect, and landcover class. Mean number of daily military sorties within sequential periods was used as a covariate in all analyses. I assessed habitat selection at 3 successive spatial scales defined as: 1) the regional geographical range of female Dall's sheep in the Yukon-Tanana uplands, 2) study areas (defined as the distribution of sheep within a localized area), and 3) selection within individual 2-week home ranges. Sheep home range size, movement rates, habitat use and selection ratios at the scale of region and study area differed between study areas, among years within study areas, and among sequential time periods within years within study areas, but did not vary in relation to military overflight intensity. I detected an effect of sorties on selection ratios at the home range scale; however, sorties explained <4% of the residual variation in these variables. I conclude that increases in intensity of military training operations during Major Flying Exercises (MFE's) over the Yukon-Tanana uplands were a relatively insignificant source of variance in activity and habitat use compared to the effects of seasons, years, and study areas"--Leaf iii
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  Human impacts on brown bears at Pack Creek, Admiralty Island, Alaska

  Warner, Susan H. (1987-05)

  Human disturbance of brown bears (Ursus arctos) was studied at Pack Creek on Admiralty Island in Southeast Alaska during 1983 and 1984. The Pack Creek watershed is closed to bear hunting. Use of the area by bear-watchers is increasing. Instantaneous scan sampling was used to observe bears at a control area with negligible human activity and at the popular Pack Creek area. Six bears were radio-collared to assess movements away from Pack Creek. Bears were crepuscular in the two areas. Individuals that were highly tolerant of visitors used the Pack Creek area during the mid-day period of high visitor use more than other bears. Over 80% of the observations of Pack Creek bears were of females, suggesting that visitor use may differentially affect sexes. Food-conditioned bears showed boldness that could cause undesirable incidents. Except for occasional sallies, Pack Creek females remained within the watershed. Males frequented several watersheds.
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  Effects of placer gold mining on stream macroinvertebrates of interior Alaska

  Wagener, Stephen Mitchell (1984-12)

  Placer gold mining is an economically and politically important industry in Alaska which can have major impacts on the water quality of streams. To determine the effect of placer mining on benthic macroinvertebrates we determined water quality characteristics and sampled benthic invertebrates in nine hydrologicalIy similar and proximally located streams. Sampled streams ranged from unmined control streams to heavily mined streams. Placer mining caused increases in turbidity, settleable solids, percent substrate embeddedness, nonfilterable residue, and total recoverable arsenic, lead, zinc, and copper. Placer mining decreased invertebrate density and biomass. Substrate embeddedness and turbidity were the best predictive descriptors of reduced invertebrate density and biomass. Invertebrate communities in mined streams usually contained higher proportions of collector-gatherers, and lower proportions of crawlers, shredders, filter-feeders, predators, and oligochaetes compared to unmined streams.
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  Photosynthetic response of phytoplankton to changing light intensity in a southcentral Alaskan lake

  Vaught, Kyle Douglas (1989-12)

  Little fresh-water work has been done (compared with published ma­rine studies) using photosynthesis-irradiance (P-I) curves to determine photosynthetic response of natural assemblages of phytoplankton to light above and below thermal stratification structures. Limnological data including physical, chemical, and algal taxonomy and biomass were collected through the summers of 1985 and 1986 at Wasilla Lake, Alaska (approximately 61oN., 148oW.). Algal photosynthesis­irradiance relationships were also determined through the summer of 1986 by means of P-I curves. P-I curve light-limited initial slope (a) was ≈2.5 times higher in phytoplankton populations at 6 m than those in the wind-mixed zone when populations were separated by thermal stratification. Wasilla Lake’s trophic status was estimated to fall between mesotrophic and eutrophic classifications. Phytoplankton in Wasilla Lake were found to require approximately 4-5 days to best adapt to a changing light environment.
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  The morphology and chemistry of two willow species in relation to moose winter browsing

  Suter, Suzanne M. (1992-12)

  This study examines the interaction between moose (Alces alces gigas) and winter dormant willows (Salix alaxensis and Salix pulchra) in Alaska, emphasizing the impact of moose browsing on the forage produced by willow. In a two year field study, plant responses were examined with clipping treatments designed to simulate browsing by moose. The plant responses examined included biomass production, plant architecture, and concentration of plant tannins. Forage selection by moose in the study area is also addressed. Results suggest that a plant response of increased growth, decreased chemical defense, and redistribution of new biomass may explain the pattern of repeated browsing of plants by moose. The responses of clipped plants indicate that moose improve the quality of their willow hosts by browsing and repeated browsing negatively affects carbon reserves of willows. Among and within plant variation in tannin content was also examined among 5. alaxensis trees. Observations are related to within and among tree measurements of growth rate.

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