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Rates of grooming, rubbing, and shaking were observed of 12 moose (Alces alces) infested with 4 levels of winter ticks (Dermacentor albipictus) and 5 uninfested control animals. Modes of grooming varied among moose and occurred with the tongue, hind feet, head, ears, antlers, teeth, and neck. Only moose with ticks used teeth and ears to groom. Uninfested moose and moose prior to being infested groomed and rubbed little. Grooming was greater immediately following than before infestation, and initial grooming and rubbing were predominant at the sites of infestation. Grooming declined in mid-winter months when nymphs develop slowly and increased in late winter and early spring when nymphs and adults actively feed; rubbing only increased in late winter and early spring. Cumulative grooming-rubbing was positively correlated with level of tick infestation and hair loss, and negatively correlated with end body weight of female calves only. Intense individual bouts of grooming and rubbing during April lasted 13–141 min. Over the entire study, cumulative grooming-rubbing in daylight hours for moose with 21,000–42,000 larvae equaled 6–28 d (μ = 12.7), and from February to April moose with 42,000 ticks groomed and rubbed on average ≥5.0–7.5 min/h. The removal of ticks was high (77–96%) indicating that grooming and rubbing are positive behavioral responses with respect to reducing the impact of winter ticks.

Broad scale analyses of winter population survey data collected between 1985 and 2015 were conducted to provide a synthesis of the current status and historical performance of 14 moose (Alces alces) populations residing in the Boreal Plain Ecozone of Saskatchewan and western Manitoba. Population time series models indicated a broad scale decline averaging 30% in moose populations across the Boreal Plain Ecozone since 2000 relative to the long-term (1985 to 2015) cumulative mean population size. Demographic patterns and rates of population change were variable among and within populations across years. We found an inverse relationship between adult sex ratio (bull:cow) and population density (R² = 0.48, P < 0.001), which suggests negative population growth (λ < 1.0) when the adult sex ratio falls below a density-dependent threshold for population growth. Winter calf recruitment (calves/cow) was positively correlated (R² = 0.12, P = 0.027) with adult sex ratio. Stable or increasing populations (λ ≥ 1.0) tended to have lower adult sex ratios relative to winter calf recruitment ratios than declining populations. Population state and vital rate relationships are useful to assess population performance and guide science-based moose management strategies in a Management-by-Objective decision-analytic framework.

Soil fungi were cultured from 24 wallows and proximal control sites in Maine and New Hampshire, USA during the autumn moose (Alces alces) breeding season of 2016 to investigate the presence of soil fungi pathogenic to winter tick larvae (Dermacentor albipictus). Twenty genera of fungi were isolated, and all are considered common in a forested ecosystem. The predominant genera isolated in wallows were pathogenic to winter tick larvae and included Aspergillus spp. (in particular A. flavus), Beauveria bassiana, Mortierella spp., Mucor spp., Paecilomyces spp., Penicillium spp., and Trichoderma spp. Wallow soils had specific characteristics and differed from proximal control sites by having: 1) lower fungal diversity, 2) a higher frequency of primary colonizers including Mortierella spp., Mucor spp., Penicillium spp., and Trichoderma spp., and 3) a more variable total amount of fungi indicative of changing (disturbed) soil conditions. We conclude that wallows are sites of soil disturbance that concentrate fungi known to be pathogenic to larval winter ticks. Fungi acquired by breeding moose using wallows might subsequently act as an on-host mechanism of tick control.

We studied age-related antler characteristics of moose (Alces alces) in Alaska Game Management Unit 20A (during 2007–2010) because of concerns about poor antler development given the population’s high density and unusually low nutritional status. A comparative study was conducted in and near our study area in the early 1970s, when moose density was lower and nutritional status was moderate. Poor antler development was an important concern for 2 reasons: 1) low annual recruitment of bull moose into the harvestable 50-inch (127-cm) antler class in the study area might restrict local harvest when the “Intensive Management” harvest objective was to specifically reduce moose density, and 2) retarded antler growth in yearling and 2-year-old bulls could bias bull:cow and yearling:cow ratios. Regression analysis of antler spread over age indicated that average antler spreads of 50 inches (127 cm) occurred when bulls reached an estimated age of 6.0 years. When using corrected annuli counts of known-age animals, bulls reached antler spreads of 50 inches (127 cm) at 5.6 years of true age in the 1970s versus 6.2 years in this study. We surmised that the difference of

I simulated selective harvest strategies of moose (Alces alces) using antler point restrictions and protection of cows with calves to assess the impact of these strategies on population age structure and potential harvest efficiency (proportion of allowed shooting opportunities). The post-hunt, adult bull:cow ratio was held constant throughout the simulations, but age structure of the bull cohort was allowed to vary. The simulation showed that protecting bulls with few antler points (

High calf mortality attributed to winter tick (Dermacentor albipictus) parasitism occurs in moose (Alces alces) populations along their southern range in the northeastern United States. We analyzed habitat use of cow and calf moose during the critical drop-off and questing periods in the winter tick life cycle to determine a potential relationship between tick density and habitat. We measured habitat use using geospatial analyses of locational data from > 200 radio-marked animals at 3 sites in New Hampshire and Maine. Moose selected for optimal habitat, defined as 4–16 year-old forest openings, regardless of season or site; this was the only land cover type used more than available (1.1–2.1X availability in home range, 1.2–3.1X availability in core range). Further, the proportional availability of optimal habitat within overlapping portions of seasonal home and core ranges exceeded the absolute proportion of optimal habitat within any one range. Temporal use of optimal habitat, which is available in relatively low proportion (15–20%) across the landscape, likely exceeds the geospatial estimates of use because moose spend 30–40% of daily activity foraging. We conclude that disproportionally abundant densities of winter ticks exist in this preferred cover type because of its selective use during the drop-off and questing periods of winter ticks.

Licenced harvest of moose (Alces alces) in British Columbia, Canada declined by approximately half over the 20-year period from 1996–2015. To better understand changes in moose populations coinciding with this period of declining harvest, we modelled population dynamics within 31 Game Management Zones (GMZs). We used aerial survey data (180 density and 159 composition surveys) combined with licensed harvest to develop 4 competing statistical models to assess population dynamics based on constant parameters and temporal trends in calf:cow ratios at 6 months, juvenile survival from 6–18 months, or cow survival. The models indicated that moose populations declined (λ < 1) in 7 GMZs (23%) from 1996–2005 and in 22 GMZs (71%) from 2006–2015. Over the 20-year period, the best model was fit with declining trends in calf:cow ratios in 8 GMZs, declining juvenile survival in 6 GMZs, and declining cow survival in 8 GMZs. Population growth rate was slightly reduced in those GMZs where licenced antlerless (cow and calf) hunting occurred but was not considered the primary factor causing population decline. Total licenced bull harvest influenced bull:cow ratios that were significantly lower in 2006–2015 (mean = 37:100) than 1995–2005 (mean = 48:100); significant predictive relationships existed between harvest rates and bull:cow ratios. Provincial moose numbers and harvest were highly correlated (r = 0.81) suggesting that declining harvest was a reaction to declining population trends. We found that the provincial moose population increased 6% from 1996–2005, subsequently declined 32% from 2006–2015, and declined 29% overall during the 20-year study period.

Understanding reproductive parameters of a population is vital to management, especially during periods of population fluctuation. Therefore, our objective was to provide the first estimates of reproductive parameters such as pregnancy rates, litter size, fecundity rates, conception dates, and fetal sex ratios for a moose (Alces alces) population in North Dakota, USA. Between 1978 and 1986, the North Dakota Game and Fish Department necropsied 54 hunter-killed cow moose which were all harvested after the rut (10 November to 12 December). Pregnancy rates for calves (n = 7), yearlings (1.5-years-old, n = 6), and adults (> 2.5-years-old, n = 41) were 0%, 100% and 95%, respectively. Mean conception date was 2 October. Overall, mean litter size was 1.76 fetuses, twinning rate was 73.3%, and mean fecundity was 1.66 fetuses and 0.85 female fetuses/cow. Fetal sex ratio did not differ from the expected 50:50 ratio, but the odds of producing at least one male calf increased with dam age, but not dam weight or litter size. This population displayed reproductive parameters consistent with an irruptive and expanding moose population.

Both declining and increasing moose (Alces alces) populations have been reported across North America over the last decade. We surveyed all jurisdictions with extant moose populations to determine the extent of these population trends. In 2014–2015, the North American moose population was estimated at ~1,000,000 animals distributed in 30 jurisdictions, which is unchanged since the turn of the century. Populations occurred in 12 Canadian provinces or territories, and in at least 18 states. In the past 5 years, moose density is believed to be increasing in 9, relatively stable in 8, and declining in 11 jurisdictions; estimates of change were unavailable in 2 jurisdictions. In 2014–2015, an estimated 425,537 licensed moose hunters harvested 82,096 moose in 23 jurisdictions. Hunter numbers increased by 39,118, whereas total harvest remained virtually unchanged from a decade earlier. Harvests by Indigenous and subsistence users, although largely unquantified, are believed substantial and important to quantify in certain jurisdictions. A variety of active and passive harvest strategies used to manage moose are discussed.

An isolate of the soil fungus Scopulariopsis brevicaulis was identified from the surface of female winter ticks (Dermacentor albipictus) collected from recently dead moose (Alces alces) calves in New Hampshire in the northeastern United States. It was the sole isolate, and it matched with 98% nucITS similarity (molecular systematics Blast match) to S. brevicaulis species from soil and other tick species. Inoculation of tick larvae and eggs with 108 spores/mL + 0.05% Tween (aqueous inoculum) resulted in mortality, reduced survival time, and recovery of S. brevicaulis from within tick tissues. Rapid water loss and death from dehydration were the pathogenic consequences of the fungal infection. Three entomopathogenic fungal isolates from laboratory culture (Beauveria bassiana, B. caledonica, and Metarhizium anisopliae) inoculated concurrently at the same dose, were slightly less pathogenic to eggs than larvae of winter ticks. We conclude that S. brevicaulis imposes a limitation on the freeliving stages of the winter tick population in specific environmental conditions, but commercial fungal treatments as used in local situations to control ticks, are impractical as a means of controlling winter tick density across moose habitats.

The health status of animals may be inferred from the patterns of hormonal concentrations and other chemical characteristics in blood samples. Baseline endocrine data representing the nutritional and reproductive condition of moose are currently unknown. In this study, we examined the seasonal patterns of 3 nutritional hormones (leptin, ghrelin, insulin-like growth factor-1) in 3 captive, non-pregnant female moose (Alces alces) fed a maintenance diet from November to August. Plasma concentrations for leptin, ghrelin, and IGF-1 averaged 1.36 ± 0.81 ng/mL, 0.229 ± 0.110 ng/mL, and 114.0 ± 30.5 ng/mL, respectively; only ghrelin displayed a seasonal change. Plasma ghrelin concentration was significantly elevated (P < 0.001) during winter months suggesting it may be sensitive to seasonal changes and indicative of nutritional status.

Sources of natural variability of blood analytes related to physiological development pose both challenges and opportunities to deriving and interpreting the most useful nutritional and health-related information from blood profiles of free-ranging animals. Preliminary evidence suggests accurate interpretation of blood profiles may be particularly important relative to newborns given their high probability of death. Our goal was to establish hematological and serum reference values for free-ranging moose (Alces alces) neonates. Sixteen neonates (8 females, 8 males) were captured and blood was sampled during 8–12 May 2013. Mean age was 2.9 days old (range = 1.4–6.0); mean body mass and hind foot length were 16.8 kg (13.8–20.5) and 46.8 cm (45.0–49.0). We present mean, 95% confidence interval and range of values for 15 hematological and 24 serum characteristics, including metabolites,chemistries, electrolytes, enzymes, and metabolic and stress hormones. We observed significant (r2 = 0.423–0.747, P ≤ 0.016) positive relationships between body mass and red blood cell and white blood cell counts, hemoglobin, and packed cell volume. Hind foot length was positively related (r2 = 0.369, P = 0.028) only to red blood cell counts. No serum constituents were affected by body size metrics, but sex influenced (P ≤ 0.052) several whole blood and serum characteristics. At the individual level, blood profiles facilitated discrimination of one individual neonate in poor nutritional condition that was not evident in the original physical examination at capture. As wildlife researchers and veterinarians increasingly assess the nutritional and health status of free-ranging moose and other species by clinical biochemistry and laboratory methods, cumulative banks of blood reference values will aid in data interpretation.

Habitat selection is a central component of the ecology of individual animals as it affects body condition, survivorship, and reproductive output. We instrumented male and female moose (Alces alces) in north-central Alaska with GPS radio-collars to assess factors we hypothesized were important to their habitat selection. Using synoptic modeling techniques, we found that models with more covariates were better predictors of moose habitat selection than more simplistic models. As expected, moose selected for habitats with high canopy cover and/or that typically have abundant forage such as 11-30 year old burned areas. However, we detected differences in habitat selection between sexes, seasons (i.e., winter versus summer), during winters of varying severity, and females with differing maternal status. During winter males moved to lower elevation areas, presumably to avoid greater snow depths, whereas females remained at relatively similar elevations. Females selected burned habitat and areas that received higher amounts of solar radiation. We found that all moose selected for lower elevation habitats closer to rivers during moderate and severe winters, but elevation was not a strong influence during mild winters. We found that females with calves avoided riparian habitats and selected areas with more forested habitat than females without calves during both summer and winter. This suggests a trade-off between maximizing forage intake and reducing predation risk for their offspring. Our and similar data are useful to improve moose management strategies and provide a benchmark against which the impacts of climate change and industrial development are assessed in this rapidly-changing region.

Provincial population and harvest estimates of moose in British Columbia, Canada were assessed over a 28-year period from 1987 to 2014. The population generally remained stable, whereas the licensed hunter harvest declined gradually by about half despite constant hunter effort. The annual population estimate ranged from a low of 157,000 moose in 1994 to a high of 190,000 in 2011, with an overall mean of 172,000 ± 9900 (SD). In 2014, the relative status of hunted populations within 7 wildlife administrative units was 1 increasing, 3 stable, and 3 in decline. The mean annual licensed harvest was 10,038 ± 2137 (SD) moose, and the mean harvest rate was 6 ± 1.3% (SD). In December 2013, British Columbia initiated a 5-year (2013–2018) research project to identify factors contributing to the decline of the moose population and licensed harvest.

Neonatal moose (Alces alces) may be prone to maternal abandonment induced by capture activities. We observed unexpectedly high levels of abandonment during the first year of our study of calf survival and cause-specific mortality in northeastern Minnesota. In response, we crafted a capture-induced abandonment contingency plan to reduce calf deaths caused by such abandonment. Locations and movements of dams relative to calves were used to gauge whether abandonment was occurring and to trigger retrieval of live calves. The Minnesota Zoo and a private facility accepted abandoned calves in viable condition. As undesirable as it is to remove calves from the population and landscape, we found it preferable to leaving them to succumb to starvation, hypothermia, or predation. We believe variations of this plan may be used in other study areas to mitigate neonate mortality due to capture-induced abandonment.

The giant liver fluke, Fascioloides magna, is a possible contributing factor to moose (Alces alces) declines in North America, but evidence linking F. magna infection directly to moose mortality is scarce. This review identifies knowledge gaps about the transmission and impact of F. magna infection on moose and proposes new directions for research and management of this parasite. We suggest that the importance of intermediate snail hosts has been largely neglected in current management discussions and warrants greater emphasis. The intermediate hosts responsible for F. magna transmission likely vary by region and recent genetic evidence suggests that F. magna was restricted to several isolated refugia during cervid extirpation events in North America. This distributional history represents several coevolutionary and pathological implications for definitive hosts of F. magna. We suggest that F. magna infections are most ecologically significant as they relate to sublethal impacts and multiple parasitic infections. In assessing infection risk on landscapes, most models rely heavily on monitoring white-tailed deer (Odocoileus virginianus), but this approach only measures risk indirectly. The reliability and accuracy of models would probably improve if snail habitat in ephemeral wetlands was included as a predictor variable.

A total of 961 harvested and 241 unharvested moose (Alces alces) carcasses and parts from throughout Sweden were examined for Elaphostrongylus alces from 1985 to 1989. When available, the central nervous system and skeletal muscles were searched for adult nematodes, and lungs and feces were examined for first-stage larvae. The parasite was distributed throughout Sweden with highest prevalence (56%) in the central region and lowest in the south (13%). Prevalence was highest in calves and old moose (>9 years) and lowest in middle-aged animals (5–9 years), with no statistical difference between sexes, although prevalence trended higher in young males. Body condition and abundance of Elaphostrongylus alces were negatively correlated, and condition was poorer in unharvested than harvested moose. A short (39–73 days) prepatent period was documented, and calves as young as 1.5 months were infected. These results indicate the importance of continued surveillance of Elaphostrongylus alces, particularly because a warming climate will likely increase abundance of intermediate mollusk hosts and possibly cause increased infection of moose.

The National Wildlife Refuge System in the United States includes about 150 million acres of lands and waters within 550 refuges managed for conservation. A variety of laws, regulations, and management polices help ensure these areas will be preserved for future generations. In a web-based survey, 35 refuges reported having established populations of moose (Alces alces) within their boundaries with nearly 40 million acres of moose habitat, 99% in Alaska. The 4 recognized subspecies of moose in North America were represented on refuges found in 12 states. Approximately 39,000 moose were reported inhabiting refuges in the USA; about 38,000 in Alaska. Only 9 refuges used management practices specifically to benefit moose, primarily prescribed or wildland fire. Moose populations on refuges varied greatly and refuge managers reported numerous concerns including climate change, illegal harvest, habitat loss or degradation, parasites, disturbance, moose-vehicle collisions, predators, and both recreational and subsistence hunting. Future management implications of these issues are discussed.

We studied variation in nucleotide sequences of the mitochondrial cytochrome-b gene to assess the phylogeny of moose (Alces alces) in general, and the position of North American moose within that phylogeny in particular. We combined North American, Asian, and European haplotypes generated for this study with 3 Eurasian haplotypes obtained from GenBank. No nucleotide variation occurred within moose from North America, whereas 3 haplotypes were present in European moose and 4 haplotypes in Asian moose. Clade structure was consistent over 6 most-parsimonious trees, with Asian haplotypes composing 1 clade, and North American and European haplotypes composing a second, albeit poorly supported clade. Low diversity of nucleotides in cytochrome-b indicated a recent ancestry among moose worldwide. Existence of 1 North American haplotype is strong evidence of a single, recent entry into the New World via the Bering land bridge, rather than multiple entries through >1 corridors. Furthermore, no phylogenetic support existed for the theory of distinct lineages of European versus Asian-North American moose.