Elk Island National Park in western Canada provides an ideal case study for an economic carrying capacity estimate because it supports high density of four species of ungulates (11/km 2 ), lacks large predators, and is enclosed by a 2.1-meter mesh fence. This high density of ungulates has created persistent management challenges by altering vegetation structure and community composition. Using linear programming, we explored optimal allocation of forage resources for bison (Bison bison bison), moose (Alces andersoni), wapiti (Cervus elaphus manitobensis) and deer (Odocoileus virginianus and O. hemionus) to maximize ungulate biomass and numbers, when constrained by use of the major forage classes and minimum viable populations (MVP) of those ungulate species that do not cross the boundary fence (bison and wapiti). Maximum numbers of animals were achieved by a stocking combination dominated by deer and bison, whereas maximum biomass was attained when bison and moose were abundant but deer were absent. Wapiti remained at MVP during all solutions. Optimal solutions consistent with current ungulate densities were associated with 7 to 11% forage removal. This is less than normally assumed for sustainable forage use, and may reflect the need to account for other biotic and abiotic losses to forage in carrying capacity models for which ungulate densities can be constrained by availability of a preferred forage class (e.g., grass) as well as forage quality. This research extends the conventional animal-unit concept to multispecies systems and provides templates based on forage biomass allocation for resource managers facing similar problems of joint stocking in different environments.

Beaked hazel (Corylus cornuta Marsh) dominates the understory of many Boreal Mixedwood forests in central Alberta including those in Elk Island National Park, where this species demonstrates a high tolerance to browsing. This research quantified changes in beaked hazel stem morphology (total twig length and number) and leaf and twig biomass of current annual growth, both inside and outside 4 newly established exclosures during the growing seasons of 1999 and 2000. At 2 sites, leaf and twig current annual growth of beaked hazel shrubs recently protected from herbivory increased significantly (P < 0.05) by 85 to 114% relative to that of browsed shrubs. At another site, the removal of browsing changed the morphology of beaked hazel shrub growth (P < 0.05), with protected shrubs producing 26% more twigs that were shorter in aggregate length by 27%. The final site exhibited no significant (P > 0.05) changes in current annual growth at the individual shrub stem level, potentially due to intense intra-specific competition. These results indicate that at several locations in the Park, the recent history of intense browsing appears to be limiting the annual growth of beaked hazel, including browse production. Despite the general increase in growth of individual beaked hazel stems, however, no changes in production were evident at the community level (P > 0.05) with the removal of browsing after 2 years. Protection from browsing did increase average beaked hazel height by 40% over the same period.

Thirty-seven adult female moose (Alces alces) from 2 distinct but adjacent populations in Elk Island National Park (EINP), Alberta, Canada (19 in north EINP and 18 in south EINP), were fitted with mortality-sensing VHF radio-collars, and radio signals were acquired daily to ascertain mortality status. At capture, serum, whole blood, and feces were collected; pregnancy was determined; teeth were aged by visual inspection; and a portion of liver was assessed by ultrasound examination. Postmortem examination was conducted on 20 suitable carcasses. Clinical pathological abnormalities, including eosinophilia, polycythemia, elevated levels of liver enzymes in serum, hemoglobin, hematocrit, and red blood cell distribution, and liver damage as seen in ultrasound images occurred only in moose from north EINP. Infected moose had 4.7 + 4.8 Fascioloides magna flukes per liver (mean + SD). The proportion of moose pregnant at capture was similar in both populations (74% in north EINP, 61% in south EINP). Proportional mortality was significantly higher in moose from the north (68%) than the south (32%). Fascioloides magna was associated as a cause of death in 7 of 14 (50%) moose in the north where cause of death was determined, while predation (n ¼ 1), acute toxemic syndrome (n ¼ 3), dystocia (n ¼ 1), and roadkill and undetermined causes (n ¼ 3) were additional causes of mortality. F. magna was associated with poor body condition and was a major cause of mortality in north EINP but not south EINP, despite very similar habitat and proximity, suggesting a significant role for these flukes in affecting health and viability of naturally infected moose populations.

Fourteen free-ranging adult wapiti (Cervus elaphus nelsoni) were captured in Banff National Park, Alberta (Canada) and held in captivity near Edmonton. A 24% suspension of triclabendazole at doses of 30 to 100 mg/kg body weight was drenched into the rumen of eight females and four ma!es. Two male wapiti were used as untreated controls. Animals were killed and examined at 4 (n = 3), 6 (n = 4), or 8 (n = 4) wk after treatment. Efficacy was 90% against immature Fascsoloides magna collected 4 wk after treatment and 98% against adult flukes collected 4, 6 or 8 wk after treatment. All 32 flukes recovered from control wapiti were active and apparently healthy. Treatment at 50 to 60 mg/kg is recommended against F. magna in wapiti. A protocol for treating infected wapiti is outlined.

Two different techniques, (1) tooth wear, tooth eruption patterns and other attributes and (2) counting annuli and seasonal growth zones in the cementum of incisor teeth, were used to estimate the age of Elk, Cervus elaphus, that were relocated from Alberta to Ontario, Canada. Age estimates for Elk ranged from 2 to 20 years, and a significant relationship was found between the ages acquired by the two methods. Critical to acquiring accurate age estimates for Elk were staff with extensive skill with respect to the aging technique utilized.