Alaskan Moose Research Articles

Predicting moose behaviors from tri-axial accelerometer data using a supervised classification algorithm

BackgroundMonitoring the behavior of wild animals in situ can improve our understanding of how their behavior is related to their habitat and affected by disturbances and changes in their environment. Moose (Alces alces) are keystone species in their boreal habitats, where they are facing environmental changes and disturbances from human activities. How these potential stressors can impact individuals and populations is unclear, in part due to our limited knowledge of the physiology and behavior of moose and how individuals can compensate for stress and disturbances they experience. We collected data from collar-mounted fine-scale tri-axial accelerometers deployed on captive moose in combination with detailed behavioral observations to train a random forest supervised classification algorithm to classify moose accelerometer data into discrete behaviors. To investigate the generalizability of our model to collared new individuals, we quantified the variation in classification performance among individuals.ResultsOur machine learning model successfully classified 3-s accelerometer data intervals from 12 Alaskan moose (A. a. gigas) and two European moose (A. a. alces) into seven behaviors comprising 97.6% of the 395 h of behavioral observations conducted in summer, fall and spring. Classification performance varied among behaviors and individuals and was generally dependent on sample size. Classification performance was highest for the most common behaviors lying with the head elevated, ruminating and foraging (precision and recall across all individuals between 0.74 and 0.90) comprising 79% of our data, and lower and more variable among individuals for the four less common behaviors lying with head down or tucked, standing, walking and running (precision and recall across all individuals between 0.28 and 0.79) comprising 21% of our data.ConclusionsWe demonstrate the use of animal-borne accelerometer data to distinguish among seven main behaviors of captive moose and discuss generalizability of the results to individuals in the wild. Our results can support future efforts to investigate the detailed behavior of collared wild moose, for example in the context of disturbance responses, time budgets and behavior-specific habitat selection.

Soft tissue sarcomas in 2 zoo-housed Alaskan moose.

Soft tissue sarcomas (STSs) are common well-described cutaneous neoplasms in many domestic species. Few cutaneous neoplasms have been reported in cervids, other than papilloma virus-induced benign cutaneous fibromas (BCFs). Two wild-caught Alaskan moose (Alces alces), housed at different North American zoos, were both presented with lameness and a mass. The gross appearance of each mass varied greatly; case 1 had a distinct, exophytic, ulcerated mass near the right carpal joint similar in appearance to a BCF, and case 2 had a pronounced swelling over the left hip. Based on histologic evaluation, both masses were diagnosed as STS. The clinical presentation of these masses included rapid growth and associated lameness; however, gross appearance was markedly different. Histopathology revealed characteristics typical of STS in other species, including spindle-shaped cells arranged in streaming sheets with ovoid nuclei. STS should be included as a differential diagnosis for moose with a cutaneous or subcutaneous soft tissue mass or swelling.

Night on Earth

Night on Earth

Behavioral modifications by a large-northern herbivore to mitigate warming conditions

BackgroundTemperatures in arctic-boreal regions are increasing rapidly and pose significant challenges to moose (Alces alces), a heat-sensitive large-bodied mammal. Moose act as ecosystem engineers, by regulating forest carbon and structure, below ground nitrogen cycling processes, and predator-prey dynamics. Previous studies showed that during hotter periods, moose displayed stronger selection for wetland habitats, taller and denser forest canopies, and minimized exposure to solar radiation. However, previous studies regarding moose behavioral thermoregulation occurred in Europe or southern moose range in North America. Understanding whether ambient temperature elicits a behavioral response in high-northern latitude moose populations in North America may be increasingly important as these arctic-boreal systems have been warming at a rate two to three times the global mean.MethodsWe assessed how Alaska moose habitat selection changed as a function of ambient temperature using a step-selection function approach to identify habitat features important for behavioral thermoregulation in summer (June–August). We used Global Positioning System telemetry locations from four populations of Alaska moose (n = 169) from 2008 to 2016. We assessed model fit using the quasi-likelihood under independence criterion and conduction a leave-one-out cross validation.ResultsBoth male and female moose in all populations increasingly, and nonlinearly, selected for denser canopy cover as ambient temperature increased during summer, where initial increases in the conditional probability of selection were initially sharper then leveled out as canopy density increased above ~ 50%. However, the magnitude of selection response varied by population and sex. In two of the three populations containing both sexes, females demonstrated a stronger selection response for denser canopy at higher temperatures than males. We also observed a stronger selection response in the most southerly and northerly populations compared to populations in the west and central Alaska.ConclusionsThe impacts of climate change in arctic-boreal regions increase landscape heterogeneity through processes such as increased wildfire intensity and annual area burned, which may significantly alter the thermal environment available to an animal. Understanding habitat selection related to behavioral thermoregulation is a first step toward identifying areas capable of providing thermal relief for moose and other species impacted by climate change in arctic-boreal regions.

Quantifying effects of environmental factors on moose harvest in Interior Alaska

Alaska moose (Alces alces) hunters have expressed concern that harvest has been challenged by warmer temperatures altering moose behavior and low water levels limiting boat access to hunting areas. The environmental impacts of these changes on moose harvest have not been quantified and are not well understood. Our objective was to assess how environmental conditions impact hunter harvest in Interior Alaska from 2000-2016. We split hunters into categories (local or non-local) and analyzed relationships during 5-day blocks that spanned the moose hunting season. The local harvest model associated high water level with increased harvest during block 4 (peak-harvest) of the hunting season (p = 0.006). A water level increase of 1 m increased daily harvest by 1.5 (p = 0.003). Non-local harvest was significantly different than null models for block 2 (p = 0.001), 3 (p = 0.048), and 4 (p = 0.001), and nearly in block 5 (p = 0.063). The non-local harvest model associated an increase in mean high temperature with reduced harvest in block 2 (p = 0.004) and block 5 (p = 0.037), and an increase in water level with increased harvest in block 3 (p = 0.083), 4 (p = 0.017), and block 5 (p = 0.092). These results reveal that local and non-local hunters are impacted differently by environmental conditions throughout the hunting season. We provided quantitative information on previously untested hypotheses regarding the impacts of dynamic environmental conditions on moose hunter harvest. Our findings provide wildlife managers with new insight on causes of variation in harvest among different user groups.

Solving optimal reactive power problem by Alaskan Moose Hunting, Larus Livens and Green Lourie Swarm Optimization Algorithms

Abstract In this paper real power loss reduction is done by Alaskan Moose Hunting Optimization (AMHO) algorithm, Larus Livens Optimization (LLO) algorithm, Green Lourie Swarm (GLS) algorithm, Green Lourie Swarm (GLS) algorithm are used to solve the reactive power problem. Projected algorithm AMHO is based on the procedure of the hunting the Alaskan Moose done by the hunter. Once the most excellent positions have been determined then every individual in the population will try to reach that most excellent position then subsequently the procedure of modernization will start. With respect to the Alaskan Moose position the hunter will adjust the position. Each hunter will move towards the most excellent position but when there is unsuccessful move done by the leader ( X leader ) , other hunters will remain in the current location. Then Larus Livens Optimization (LLO) algorithm is applied to solve the problem. Larus Livens are normally yellow footed, they normally migrate season to season and also they possess attacking mode behavior to get the food. In general Larus Livens are searcher and hunter. They eat reptiles, small fish and so on. They have ability to catch the fish and also earth worms which concealed below the earth. In the projected algorithm two deeds of Larus Livens are mainly utilized to model the exploration and exploitation. Through migration Larus Livens will move to other places it has been modeled as Exploration in the proposed algorithm. Attacking behavior of the Larus Livens has been imitated to model the exploitation. Then Green Lourie Swarm (GLS) algorithm is applied to solve the problem. Proposed GLS algorithm has been modeled based on the social behavior of the Green Lourie bird. GLS algorithm has been formulated based on the foraging behavior, vigilance behavior and flight behavior. In the algorithm Periodic mode has been implemented to enhance the diversity of the swarm. At first Proposed AMHO, LLO, GLS algorithms is evaluated in IEEE 30 bus system with considering voltage stability index and in standard IEEE 14, 30, 57, 300 bus test systems without considering the voltage stability index. Real power loss minimization, voltage deviation minimization, and voltage stability index augmentation has been achieved.

The Alces alces awards

The <i>Alces alces</i> awards

New roles in hemicellulosic sugar fermentation for the uncultivated Bacteroidetes family BS11

Ruminants have co-evolved with their gastrointestinal microbial communities that digest plant materials to provide energy for the host. Some arctic and boreal ruminants have already shown to be vulnerable to dietary shifts caused by changing climate, yet we know little about the metabolic capacity of the ruminant microbiome in these animals. Here, we use meta-omics approaches to sample rumen fluid microbial communities from Alaskan moose foraging along a seasonal lignocellulose gradient. Winter diets with increased hemicellulose and lignin strongly enriched for BS11, a Bacteroidetes family lacking cultivated or genomically sampled representatives. We show that BS11 are cosmopolitan host-associated bacteria prevalent in gastrointestinal tracts of ruminants and other mammals. Metagenomic reconstruction yielded the first four BS11 genomes; phylogenetically resolving two genera within this previously taxonomically undefined family. Genome-enabled metabolic analyses uncovered multiple pathways for fermenting hemicellulose monomeric sugars to short-chain fatty acids (SCFA), metabolites vital for ruminant energy. Active hemicellulosic sugar fermentation and SCFA production was validated by shotgun proteomics and rumen metabolites, illuminating the role BS11 have in carbon transformations within the rumen. Our results also highlight the currently unknown metabolic potential residing in the rumen that may be vital for sustaining host energy in response to a changing vegetative environment.

Harvest of female moose at high density: modelling the impacts of harvest on population size and biomass yield

Management of harvested moose Alces alces populations at or above ecological carry capacity risks habitat degradation, nutritional limitation, and increased population vulnerability during severe winters. Selective female harvests have the potential to curb population growth while providing hunting opportunities. Using a female‐only, stage‐structured population model parameterized from an Interior Alaska moose population, we examined numbers of harvested individuals and biomass yield associated with reducing a population from 14 500 to 10 000 individuals over 3, 5 and 8 years. We compared harvest of cow—calf pairs versus unaccompanied females. The higher potential for adult female survival compared with calf survival to impact population growth rate resulted in higher yields from cow—calf harvests. Achieving the population objective required the mean annual harvest of 889, 626 and 477 cow—calf pairs or 1161, 805 and 605 unaccompanied females, for the three harvest durations, respectively. Over a five‐year period, cow—calf harvests yielded approximately 56% more individuals and 17% greater biomass, an estimated difference of 130 metric tonnes. The two harvest scenarios resulted in similar stage distributions and population growth rates following the termination of harvest. While the cow—calf harvests can provide higher yields, they also require substantially higher hunter effort to achieve population objectives. The harvest of unaccompanied females will result in greater population reduction per individual harvested and will therefore be the preferable strategy when hunter effort is limited. In addition, the large harvest numbers necessary to achieve the modelled management goal, suggest that some moose populations may escape the range where they can be easily be controlled through female harvest, especially when harvest is limited by hunter interest or access.

Range Expansion of Moose in Arctic Alaska Linked to Warming and Increased Shrub Habitat.

Twentieth century warming has increased vegetation productivity and shrub cover across northern tundra and treeline regions, but effects on terrestrial wildlife have not been demonstrated on a comparable scale. During this period, Alaskan moose (Alces alces gigas) extended their range from the boreal forest into tundra riparian shrub habitat; similar extensions have been observed in Canada (A. a. andersoni) and Eurasia (A. a. alces). Northern moose distribution is thought to be limited by forage availability above the snow in late winter, so the observed increase in shrub habitat could be causing the northward moose establishment, but a previous hypothesis suggested that hunting cessation triggered moose establishment. Here, we use recent changes in shrub cover and empirical relationships between shrub height and growing season temperature to estimate available moose habitat in Arctic Alaska c. 1860. We estimate that riparian shrubs were approximately 1.1 m tall c. 1860, greatly reducing the available forage above the snowpack, compared to 2 m tall in 2009. We believe that increases in riparian shrub habitat after 1860 allowed moose to colonize tundra regions of Alaska hundreds of kilometers north and west of previous distribution limits. The northern shift in the distribution of moose, like that of snowshoe hares, has been in response to the spread of their shrub habitat in the Arctic, but at the same time, herbivores have likely had pronounced impacts on the structure and function of these shrub communities. These northward range shifts are a bellwether for other boreal species and their associated predators.

High-throughput DNA sequencing of the moose rumen from different geographical locations reveals a core ruminal methanogenic archaeal diversity and a differential ciliate protozoal diversity.

Moose rumen samples from Vermont, Alaska and Norway were investigated for methanogenic archaeal and protozoal density using real-time PCR, and diversity using high-throughput sequencing of the 16S and 18S rRNA genes. Vermont moose showed the highest protozoal and methanogen densities. Alaskan samples had the highest percentages of Methanobrevibacter smithii, followed by the Norwegian samples. One Norwegian sample contained 43 % Methanobrevibacter thaueri, whilst all other samples contained < 10 %. Vermont samples had large percentages of Methanobrevibacter ruminantium, as did two Norwegian samples. Methanosphaera stadtmanae represented one-third of sequences in three samples. Samples were heterogeneous based on gender, geographical location and weight class using analysis of molecular variance (AMOVA). Two Alaskan moose contained >70 % Polyplastron multivesiculatum and one contained >75 % Entodinium spp. Protozoa from Norwegian moose belonged predominantly (>50 %) to the genus Entodinium, especially Entodinium caudatum. Norwegian moose contained a large proportion of sequences (25–97 %) which could not be classified beyond family. Protozoa from Vermont samples were predominantly Eudiplodinium rostratum (>75 %), with up to 7 % Diploplastron affine. Four of the eight Vermont samples also contained 5–12 % Entodinium spp. Samples were heterogeneous based on AMOVA, principal coordinate analysis and UniFrac. This study gives the first insight into the methanogenic archaeal diversity in the moose rumen. The high percentage of rumen archaeal species associated with high starch diets found in Alaskan moose corresponds well to previous data suggesting that they feed on plants high in starch. Similarly, the higher percentage of species related to forage diets in Vermont moose also relates well to their higher intake of fibre.

Design and validation of four new primers for next-generation sequencing to target the 18S rRNA genes of gastrointestinal ciliate protozoa.

Four new primers and one published primer were used to PCR amplify hypervariable regions within the protozoal 18S rRNA gene to determine which primer pair provided the best identification and statistical analysis. PCR amplicons of 394 to 498 bases were generated from three primer sets, sequenced using Roche 454 pyrosequencing with Titanium, and analyzed using the BLAST database (NCBI) and MOTHUR version 1.29. The protozoal diversity of rumen contents from moose in Alaska was assessed. In the present study, primer set 1, P-SSU-316F and GIC758R (amplicon of 482 bases), gave the best representation of diversity using BLAST classification, and the set amplified Entodinium simplex and Ostracodinium spp., which were not amplified by the other two primer sets. Primer set 2, GIC1080F and GIC1578R (amplicon of 498 bases), had similar BLAST results and a slightly higher percentage of sequences that were identified with a higher sequence identity. Primer sets 1 and 2 are recommended for use in ruminants. However, primer set 1 may be inadequate to determine protozoal diversity in nonruminants. The amplicons created by primer set 1 were indistinguishable for certain species within the genera Bandia, Blepharocorys, Polycosta, and Tetratoxum and between Hemiprorodon gymnoprosthium and Prorodonopsis coli, none of which are normally found in the rumen.

Sufentanil Citrate Immobilization of Alaskan Moose Calves

Free-ranging Alaskan moose calves (Alces alces gigas) were immobilized with 0.12 mg/kg sufentanil (S; n=16), 0.12 mg/kg sufentanil plus 0.27 mg/kg xylazine (SX; n=11), or 0.007 mg/kg carfentanil plus 0.36 mg/kg xylazine (CX; n=13). Immobilants were antagonized with 1.2 mg/kg naltrexone (S) or 1.2 mg/kg naltrexone plus 2.4 mg/kg tolazoline (SX, CX). There were no differences in induction (P ≥ 0.29) or processing (P ≥ 0.44) times between groups. Moose given either S or SX had significantly shorter recovery times than moose given CX (P=0.001) and recovery times from S were shorter than from SX (P=0.02). Oxygen saturation values for all groups averaged 85 ± 8%, but were significantly higher (P=0.048) for CX (89 ± 7%) than for S (82 ± 8%). Based on these data, sufentanil at 0.1 mg/kg or sufentanil at 0.1 mg/kg plus xylazine at 0.25 mg/kg could provide effective remote immobilization for Alaskan moose calves and could be substituted for carfentanil or thiafentanil should the need arise.

Vocalizations by Alaskan moose: female incitation of male aggression

Evidence of female fomentation of male–male aggression as a mechanism of mate choice is rare, especially in mammals. Female choice of mates in polygynous species may be masked by intense male competition or by males attempting to restrict female choice. We studied protest moans of female Alaskan moose Alces alces gigas in interior Alaska, USA, from 1987 to 1990, to determine if moans incited male–male aggression. Alaskan moose exhibit a mating system in which one dominant male (the harem master) herds, defends, courts, and attempts to mate with females in his harem. Protest moans were given by females only in response to courtship. We hypothesized that if protest moans were related to females reducing harassment and exercising mate choice, females should give protest moans more frequently when courted by small males and less often when courted by large males, and that rates of male–male aggression would be elevated following protest moans. Harems were composed of one large male, with a mean of 4.4 females (median = 3 females); 10% of 132 harems included ≥10 females. The temporal pattern of protest moans from late August through November was associated with, but tended to lag behind, mating behavior. The rate of protest moans given by females decreased with increasing size of males courting them. Male–male aggression was significantly less during periods without protest moans than during periods in which protest moans occurred. These results indicate that female moose gave protest moans to reduce harassment by smaller males, and assure a mating opportunity with the most dominant male. Such a subtle mechanism of indirect mate choice by females may occur in other vertebrates in which choice is limited by a mating system in which male–male combat and male dominance over females reduces opportunities for female choice. The importance of female choice may be undervalued in studies of sexual selection in mammals.

Molecular identification of Taenia spp. in wolves ( Canis lupus), brown bears ( Ursus arctos) and cervids from North Europe and Alaska

Taenia tapeworms of Finnish and Swedish wolves ( Canis lupus) and Finnish brown bears ( Ursus arctos), and muscle cysticerci of Svalbard reindeer ( Rangifer tarandus platyrhynchus), Alaskan Grant's caribou ( Rangifer tarandus granti) and Alaskan moose ( Alces americanus) were identified on the basis of the nucleotide sequence of a 396 bp region of the mitochondrial cytochrome c oxidase subunit 1 gene. Two species were found from wolves: Taenia hydatigena and Taenia krabbei. The cysticerci of reindeer, caribou and one moose also represented T. krabbei. Most of the cysticercal specimens from Alaskan moose, however, belonged to an unknown T. krabbei-like species, which had been reported previously from Eurasian elks ( Alces alces) from Finland. Strobilate stages from two bears belonged to this species as well. The present results suggest that this novel Taenia sp. has a Holarctic distribution and uses Alces spp. as intermediate and ursids as final hosts.

Browse biomass removal and nutritional condition of moose Alces alces

AbstractWe present methodology for assessing browse removal to help evaluate resource limitation among moose Alces alces populations in large, potentially remote areas of boreal forest. During 2000‐2007, we compared proportional removal (ratio of browse consumption to browse production) in eight areas of Interior Alaska, USA, with multi‐year twinning rates of the respective moose populations. Several prior studies concluded that twinning rate provided an index of the nutritional condition of moose. We theorized that a plant‐based sampling of proportional use of browse by moose in late winter would inversely correlate with the nutritional condition of moose. We sampled willow Salix spp., quaking aspen Populus tremuloides, balsam poplar P. balsamifera and Alaska paper birch Betula neoalaskana, i.e. plants with current annual growth (CAG) between 0.5 and 3.0 m above ground. We estimated the biomass of CAG and biomass removed by moose based on bite diameters and diameter‐mass regressions specific to each browse species. Mean browse removal by moose varied among study areas from 9 to 43% of CAG. Moose twinning rate (range: 7‐64%) was inversely correlated with proportional browse removal by moose (Spearman's rho = −0.863, P &lt; 0.005). Proportional browse removal appeared useful in linking foraging ecology and population dynamics of moose in Alaska, and the technique may be used to quantify resource limitation in moose populations inhabiting boreal forest in a broader geographic region.

Sex and scale: implications for habitat selection by Alaskan mooseAlces alces gigas

AbstractWe examined the roles of sex and spatial scale in habitat selection by Alaskan mooseAlces alces gigas. We GPS‐collared 11 female and seven male adult moose in the Tongass National Forest, Alaska, USA, during 2002‐2004. We predicted that adult male and female moose would be spatially separated outside of the mating season, consistent with hypotheses attributing sexual segregation among sexually dimorphic ruminants to allometric differences in body and gastrointestinal size, and resulting differential needs for nutrient requirements by the sexes (the gastrocentric hypothesis), and varying risks of predation (the predation hypothesis) between sexes, especially for females with young. We predicted that habitat selection would be similar between sexes during the mating season, but dissimilar and occur at different scales during periods of late gestation and lactation. We expected that during segregation, females would select for a higher percentage of forested cover and a higher edge density than males to reduce predation risk on their young. Furthermore, we examined whether differences in scale of habitat selected between the sexes was related to home‐range size. Multi‐response Permutation Procedures (MRPP) analysis indicated that the spatial distributions of adult males and females differed, particularly near or during parturition. The sexes selected habitats similarly during the mating season (rut), when sexes generally were aggregated, whereas sexes exhibited differential habitat selection during spring, when sexes were segregated. Habitat selection by both sexes was best explained by vegetation and landscape composition tabulated within 1,000‐m radii centered on GPS locations of moose. The sexes did not differ in the scale at which they selected habitats. Mean size of the annual home range was 76 km2for females and 125 km2for males, but size of home range was not related to scale of habitat selection by moose. Our results indicate that females were likely selecting habitat with high‐quality forage while minimizing predation risk during periods of sexual segregation, whereas males were selecting habitat that allowed high forage intake, which together provide support for both the gastrocentric and the predation hypotheses.

Population Structure and Genetic Diversity of Moose in Alaska

Moose (Alces alces) are highly mobile mammals that occur across arboreal regions of North America, Europe, and Asia. Alaskan moose (Alces alces gigas) range across much of Alaska and are primary herbivore consumers, exerting a prominent influence on ecosystem structure and functioning. Increased knowledge gained from population genetics provides insights into their population dynamics, history, and dispersal of these unique large herbivores and can aid in conservation efforts. We examined the genetic diversity and population structure of moose (n = 141) with 8 polymorphic microsatellites from 6 regions spanning much of Alaska. Expected heterozygosity was moderate (H(E) = 0.483-0.612), and private alleles ranged from 0 to 6. Both F(ST) and R(ST) indicated significant population structure (P < 0.001) with F(ST) < 0.109 and R(ST) < 0.125. Results of analyses from STRUCTURE indicated 2 prominent population groups, a mix of moose from the Yakutat and Tetlin regions versus all other moose, with slight substructure observed among the second population. Estimates of dispersal differed between analytical approaches, indicating a high level of historical or current gene flow. Mantel tests indicated that isolation-by-distance partially explained observed structure among moose populations (R(2) = 0.45, P < 0.01). Finally, there was no evidence of bottlenecks either at the population level or overall. We conclude that weak population structure occurs among moose in Alaska with population expansion from interior Alaska westward toward the coast.

Palmated antlers of moose may serve as a parabolic reflector of sounds

It has been postulated that the excellent sense of hearing in moose is mostly due to: (1) the large surface of the external ear, (2) better stereophony due to the large distance between ears, (3) independently movable, extremely adjustable pinna, and (4) the amplification of sounds reflected by the palms of the antlers. The last factor, possible reflection of sounds into pinna by the palm of the antlers, was tested in this study on a large antler trophy of Alaskan moose. The reception of a standard tone, broadcast from the frontally placed speaker, was recorded by a sound level meter located in an artificial moose ear. Three locations of the ear, as positioned relative to the speaker, e.g., frontward, sideward, and backward, were tested. The weakest reception was recorded in the backward position of the ear. If the sound pressure measured in the frontward position was set as 100%, the sound pressure in the backward position was 79%. The strongest reception was recorded when the artificial ear was positioned toward the center of the antler palm. In this position, the sound pressure was 119% relative to the frontward position. These findings strongly indicate that the palm of moose antlers may serve as an effective, parabolic reflector which increases the acoustic pressure of the incoming sound.

Ranking Alaska Moose Nutrition: Signals to Begin Liberal Antlerless Harvests

Abstract: We focused on describing low nutritional status in an increasing moose (Alces alces gigas) population with reduced predation in Game Management Unit (GMU) 20A near Fairbanks, Alaska, USA. A skeptical public disallowed liberal antlerless harvests of this moose population until we provided convincing data on low nutritional status. We ranked nutritional status in 15 Alaska moose populations (in boreal forests and coastal tundra) based on multiyear twinning rates. Data on age‐of‐first‐reproduction and parturition rates provided a ranking consistent with twinning rates in the 6 areas where comparative data were available. Also, short‐yearling mass provided a ranking consistent with twinning rates in 5 of the 6 areas where data were available. Data from 5 areas implied an inverse relationship between twinning rate and browse removal rate. Only in GMU 20A did nutritional indices reach low levels where justification for halting population growth was apparent, which supports prior findings that nutrition is a minor factor limiting most Alaska moose populations compared to predation. With predator reductions, the GMU 20A moose population increased from 1976 until liberal antlerless harvests in 2004. During 1997‐2005, GMU 20A moose exhibited the lowest nutritional status reported to date for wild, noninsular, North American populations, including 1) delayed reproduction until moose reached 36 months of age and the lowest parturition rate among 36‐month‐old moose (29%, n = 147); 2) the lowest average multiyear twinning rates from late‐May aerial surveys (x = 7%, SE = 0.9%, n = 9 yr, range = 3‐10%) and delayed twinning until moose reached 60 months of age; 3) the lowest average mass of female short‐yearlings in Alaska (x̄ = 155 ± 1.6 [SE] kg in the Tanana Flats subpopulation, up to 58 kg below average masses found elsewhere); and 4) high removal (42%) of current annual browse biomass compared to 9‐26% elsewhere in boreal forests. When average multiyear twinning rates in GMU 20A (sampled during 1960‐2005) declined to &lt;10% in the mid‐ to late 1990s, we began encouraging liberal antlerless harvests, but only conservative annual harvests of 61‐76 antlerless moose were achieved during 1996‐2001. Using data in the context of our broader ranking system, we convinced skeptical citizen advisory committees to allow liberal antlerless harvests of 600‐690 moose in 2004 and 2005, with the objective of halting population growth of the 16,000‐17,000 moose; total harvests were 7‐8% of total prehunt numbers. The resulting liberal antlerless harvests served to protect the moose population's health and habitat and to fulfill a mandate for elevated yield. Liberal antlerless harvests appear justified to halt population growth when multiyear twinning rates average ≤10% and ≥1 of the following signals substantiate low nutritional status: &lt;50% of 36‐month‐old moose are parturient, average multiyear short‐yearling mass is &lt;175 kg, or &gt;35% of annual browse biomass is removed by moose.