Evaluating tools used to estimate and manage browse available to wintering moose on the Copper River Delta, Alaska

• Main Author: Smythe, Sharon E.
• Other Authors: Sanchez, Dana M., Hibbs, David E., Epps, Clinton W., Mata-Gonzalez, Ricardo, Fisheries and Wildlife, Oregon State University. Graduate School
• Format: Master Thesis
• Language: English; unknown
• Published: Oregon State University
• Subjects: Moose > Wintering > Alaska > Copper River Delta; Ecological carrying capacity > Alaska > Copper River Delta; Willows > Alaska > Copper River Delta > Management; Browse (Animal food) > Alaska > Copper River Delta > Management; Moose > Food > Alaska > Copper River Delta; Alces alces; Alaska
• Online Access: https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/p5547v20z

Ungulates comprise some of the most well researched and intensely managed wildlife populations on earth. As such, they are recognized as ideal study subjects for developing and modifying management tools or theories (Danell et al. 1994, Shipley 2010). An introduced moose (Alces alces gigas) population on the Copper River Delta (CRD; Delta) of south-central Alaska functions as a valuable resource for the residents of Cordova and an isolated research population on which to test managerial techniques. Since its introduction (1949-1958), the founding population of 23 moose has grown to over 830 in 2013, divided into two sub-populations. However, in 1964, the largest earthquake recorded in U.S. history (9.2 magnitude) uplifted the Delta by 1.0-4.0 m, initiating delta-wide changes in hydrology, vegetation distributions, and successional processes. The proportion of stands dominated by woody species, especially alder (Alnus viridis sinuata) and spruce (Picea sitchensis), increased visibly. Furthermore, previous research (1987-89) observed that 90% of the moose on the western region of the Delta wintered within 9-24% of the total land area, possibly restricting their available winter browse. Because moose diets on the CRD are dominated by willows (Salix spp.), managers were concerned that the combined effects of a restricted winter range and earthquake-initiated vegetation changes would negatively influence the population. Managers have responded to this concern by 1) supporting work to estimate the nutritional carrying capacity (NCC; i.e., the forage available to a population within a specified area and time) of the Delta, and 2) by exploring the feasibility of mechanical treatment as a means of stimulating browse production for the moose. Thus, the objectives of this thesis were to 1) explore the factors influencing NCC for moose on the west CRD while combining updated digital and field-collected data to estimate NCC, and 2) to assess the effects of mechanical treatment on the production of moose browse across stand ...