• Population Characteristics, Ecology, And Management Of Wolverines In Northwestern Alaska (Gulo-Gulo)

      Magoun, Audrey J. (1985)
      A radiotelemetry study of wolverines was initiated in 1978 as part of a larger research program sponsored by the U.S. Fish and Wildlife Service in northwestern Alaska. The primary goal of this research was to determine aspects of wolverine behavior and ecology that are important to the management of wolverines in northwestern Alaska. Between April 1978 and May 1981, 26 wolverines were captured, 12 males and 14 females; 23 were radiocollared. Nine wolverine kits in five litters were produced by three of the radiocollared females between March 1978 and May 1982. The average rate of reproduction for the study population was 0.6 kits/female/year. Birth of kits occurred in early March. Kits grew rapidly, reaching adult size by November. Resident female wolverines maintained home ranges that were exclusive of other females except their offspring; average summer home range size was 94 km('2). Data were insufficient to determine if adult male home ranges overlapped; overlap did occur between adult and juvenile males. Summer home range size for adult males averaged 626 km('2). Data were insufficient to determine annual home range size. Denning and raising young had a major influence on the movement patterns of adult females. Movements of males were influenced by breeding behavior from late winter through summer. Wolverine social structure appeared to be typical of the intrasexual territoriality of solitary carnivores. Wolverines scentmarked frequently using urine and secretions from the ventral gland and anal sacs. Caribou and ground squirrels were the most important foods. Food was apparently limited during the winter months and influenced wolverine movements and productivity. The presence of caribou and moose may be the most important factor influencing wolverine populations in northwestern Alaska. Wolverines do not appear to be overexploited at this time, but an attempt should be made to obtain more accurate harvest statistics and baseline data to establish wolverine population size and structure in northwestern Alaska.
    • The Nutrient Flow System: Control Of Nutrient Availability And Measurement Of Ion Uptake

      Bishop, Daniel R.; Kokjer, Ken (1990)
      An instrumentation and control system was built to maintain a constant nutrient supply to plants in flowing solution culture. The microcomputer based system controls the concentration of mineral nutrients, pH, root temperature, and water level. The nutrient ion concentrations controlled by the computer are nitrate, potassiuum, and ammonium. Ion-specific electrodes used as sensors are automatically calibrated before each measurement. Computer controlled valve manifolds and a 16-channel peristaltic pump mix aliquots of nutrient solution with ionic strength adjuster for improved electrode operation. A mathematical analysis of the performance of the Nutrient Flow System shows how the error introduced in system components contributes to error in measurements, and how experimental parameters affect accuracy. Results of plant growth trials are given, and statistical techniques for evaluating growth trial results are discussed. Over a sixteen day experiment with a target concentration of 1.0 $\times$ 10$\sp{-4}$-M NO$\sbsp{3}{-}$, the variance of the concentration was 2.4 $\times$ 10$\sp{-6}$. The uptake over the experiment was 91.6 grams of nitrate. There was a 1.5% discrepancy between actual uptake and the uptake calculated by the system. <p>