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Big game hunting statisticsBig game hunting statisticsTextBear Hunting Statistics
Deer Hunting Statistics
Desert Bighorn Sheep Hunting Statistics
Elk Hunting Statistics
Moose Hunting Statistics
Mountain Goat Hunting Statistics
Mountain Lion Statistics
Pronghorn Hunting Statistics
Rocky Mountain Bighorn Sheep Hunting Statistics
Type:Text
Description:Big Game Draw & Hunting Statistics In an effort to assist Colorado's big game hunters applying for the draw, Colorado Parks and Wildlife provides the following draw and hunting season information. These reports show how many licenses were available in all big game management units throughout Colorado, how many hunters applied for those limited licenses, how many of those hunters were successful drawing and how many preference points it took to be successful. [show more]
Status and trends of moose populations and hunting opportunity in the western United StatesStatus and trends of moose populations and hunting opportunity in the western United StatesTextAlces alces shirasi
Colorado
Hunter harvest
Idaho
Montana
Nevada
Oregon
Population trends
Range
Shiras moose
Utah
Washington
Wyoming
Type:Text
Subject:Alces alces shirasi
Colorado
Hunter harvest
Idaho
Montana
Nevada
Oregon
Population trends
Range
Shiras moose
Utah
Washington
Wyoming
Description:We review the state of knowledge of moose (Alces alces shirasi) in the western US with respect to the species’ range, population monitoring and management, vegetative associations, licensed hunting opportunity and hunter harvest success, and hypothesized limiting factors. Most moose monitoring programs in this region rely on a mixture of aerial surveys of various formats and hunter harvest statistics. However, given the many challenges of funding and collecting rigorous aerial survey data for small and widespread moose populations, biologists in many western states are currently exploring other potential avenues for future population monitoring. In 2015, a total of 2,263 hunting permits were offered among 6 states, with 1,811 moose harvested and an average success rate per permit-holder of 80%. The spatial distribution of permits across the region shows an uneven gradient of hunting opportunity, with some local concentrations of opportunity appearing consistent across state boundaries. On average, hunting opportunity has decreased across 56% of the western US, remained stable across 17%, and increased across 27% during 2005–2015. Generally, declines in hunting opportunity for moose are evident across large portions (62–89%) of the “stronghold” states where moose have been hunted for the longest period of time (e.g., Idaho, Montana, Utah, and Wyoming). In contrast, increases in opportunity appear more common at peripheries of the range where populations have expanded, including most of Colorado, northeastern Washington, southern Idaho, and eastern Montana. There are many factors of potential importance to moose in this region, including parasites, predators, climate, forage quality, forage quantity, and humans. State wildlife agencies are currently conducting a variety of research focused on population vital rates, the development of monitoring techniques, forage quality, trace mineral levels, and evaluation of relative impacts among potential limiting factors. [show more]
Effects of willow nutrition and morphology on calving success of mooseEffects of willow nutrition and morphology on calving success of mooseTextAlces alces
Calving success
Colorado
Moose, nutrition
Reproduction
Salix
Willow
Type:Text
Subject:Alces alces
Calving success
Colorado
Moose, nutrition
Reproduction
Salix
Willow
Description:Across much of North America, populations of moose (Alces alces) are declining because of disease, predation, climate change, and anthropogenic-driven habitat loss. Contrary to this trend, populations of moose in Colorado, USA, have continued to grow. Studying successful (i.e., persistent or growing) populations of moose can facilitate continued conservation by identifying habitat features critical to persistence of moose. We hypothesized that moose using habitat with higher quality willow (Salix spp.) would have a higher probability of having a calf-at-heel (i.e., calving success). We evaluated moose calving success using repeated ground observations of collared individuals with calves in an occupancy model framework to account for detection probability. We then evaluated the impact of willow habitat quality and nutrition on moose calving success by studying 2 spatially segregated populations of moose in Colorado. Last, we evaluated correlations between willow characteristics (browse intensity, height, cover, leaf length, and species) and willow nutrition (dry matter digestibility [DMD]) to assess the utility of using those characteristics to assess willow nutrition. We found willow height and cover had a high probability of being positively associated with higher individual-level calving success. Willow DMD, browse intensity, and leaf length were not predictive of individual moose calving success; however, the site with higher mean DMD consistently had higher mean estimates of calving success for the same year. Our results suggest surveying DMD is likely not a useful metric for assessing differences in calving success of individual moose but may be of use at population levels. Further, the assessment of willow morphology and density may be used to identify areas that support higher levels of moose calving success. [show more]
Moose calf detection probabilities: quantification and evaluation of a ground-based survey techniqueMoose calf detection probabilities: quantification and evaluation of a ground-based survey techniqueTextAlces alces
Colorado
Detection probability
Ground-surveys
Moose
Occupancy models
Type:Text
Subject:Alces alces
Colorado
Detection probability
Ground-surveys
Moose
Occupancy models
Description:Survey data improve population management, yet those data often have associated bias. We quantified one source of bias in moose survey data (observer detection probability, p), by using repeated ground-observations of calves-at-heel of radio-collared moose in Colorado, USA. Detection probabilities, which varied both spatially and temporally, were estimated using an occupancy-modelling framework. We provide an efficient offset for modelled calf-at-heel occupancy (ψ) estimates that accommodates summer calf mortality. Detection probabilities were most efficiently modelled with seasonal variation, with the lowest probability of detecting calves-at-heel occurring during parturition (i.e. May) and later autumn periods (after August). Our most efficiently modelled detection probability estimate for summer was 0.80 (SE = 0.05). During the four years of this study, ψ estimates ranged from 0.54–0.84 (SE = 0.08–0.11). Accounting for 91.7% monthly calf survival corrected ψ estimates downward (ψ = 0.42–0.65). Our results suggest that repeated ground-based observations of individual cow moose, during summer months, can be can a cost-effective strategy for estimating a productivity parameter for moose. Ground survey results can be further improved by accounting for calf mortality. [show more]
Estimating the risk of elk-to-livestock brucellosis transmission in MontanaEstimating the risk of elk-to-livestock brucellosis transmission in MontanaTextBrucella abortus
Cervus canadensis
Cross-species pathogen spillover
Habitat selection
Human-wildlife conflict
Resource selection function
Wildlife disease
Type:Text
Subject:Brucella abortus
Cervus canadensis
Cross-species pathogen spillover
Habitat selection
Human-wildlife conflict
Resource selection function
Wildlife disease
Description:Wildlife reservoirs of infectious disease are a major source of human-wildlife conflict because of the risk of potential spillover associated with commingling of wildlife and livestock. In Montana, the presence of brucellosis (Brucella abortus) in free-ranging elk (Cervus canadensis) populations is of significant management concern because of the risk of disease transmission from elk to livestock. To help mitigate potential conflict, we identified how spillover risk changes through space and time using a combination of elk population, disease, and movement data. We developed resource selection functions using telemetry data from 223 female elk to predict the relative probability of female elk occurrence on a daily basis during the 15 February-30 June transmission risk period. We combined these spatiotemporal predictions with elk seroprevalence, demography, and abortion timing data to identify when and where abortions (the primary transmission route of brucellosis) were most likely to occur. Additionally, we integrated these predictions with spatiotemporal data on livestock distribution to estimate the daily risk of livestock encountering brucellosis-induced elk abortions. We estimated that a minimum of ~17,500 adult female elk lived within our study area, which resulted in a conservative estimate of ~525 brucellosis-induced abortions each year. We predicted that approximately half of the transmission events occurred on livestock properties and 98% of those properties were private ranchlands as opposed to state or federal grazing allotments. Our fine-resolution (250-m spatial, 1-day temporal), large-scale (17,732 km2) predictions of potential elk-to-livestock transmission risk provide wildlife and livestock managers with a useful tool to identify higher risk areas in space and time and proactively focus actions in these areas to separate elk and livestock to reduce spillover risk. [show more]
Modeling elk-to-livestock transmission risk to predict hotspots of brucellosis spilloverModeling elk-to-livestock transmission risk to predict hotspots of brucellosis spilloverTextBrucella abortus
Cervus canadensis
Cross-species pathogen spillover
Greater Yellowstone Ecosystem
Habitat selection
Human-wildlife conflict
Resource selection function
Wildlife disease
Type:Text
Subject:Brucella abortus
Cervus canadensis
Cross-species pathogen spillover
Greater Yellowstone Ecosystem
Habitat selection
Human-wildlife conflict
Resource selection function
Wildlife disease
Description:Wildlife reservoirs of infectious disease are a major source of human-wildlife conflict because of the risk of potential spillover associated with commingling of wildlife and livestock. In the Greater Yellowstone Ecosystem, the presence of brucellosis (Brucella abortus) in free-ranging elk (Cervus canadensis) populations is of significant management concern because of the risk of disease transmission from elk to livestock. We identified how spillover risk changes through space and time by developing resource selection functions using telemetry data from 223 female elk to predict the relative probability of female elk occurrence daily during the transmission risk period. We combined these spatiotemporal predictions with elk seroprevalence, demography, and transmission timing data to identify when and where abortions (the primary transmission route of brucellosis) were most likely to occur. Additionally, we integrated our predictions of transmission risk with spatiotemporal data on areas of potential livestock use to estimate the daily risk to livestock. We predicted that approximately half of the transmission risk occurred on areas where livestock may be present (i.e., private property or grazing allotments). Of the transmission risk that occurred in livestock areas, 98% of it was on private ranchlands as opposed to state or federal grazing allotments. Disease prevalence, transmission timing, host abundance, and host distribution were all important factors in determining the potential for spillover risk. Our fine-resolution (250-m spatial, 1-day temporal), large-scale (17,732 km2) predictions of potential elk-to-livestock transmission risk provide wildlife and livestock managers with a useful tool to identify higher risk areas in space and time and proactively focus actions in these areas to separate elk and livestock to reduce spillover risk. [show more]
Evaluation of techniques to reduce deer and elk damage to agricultural cropsEvaluation of techniques to reduce deer and elk damage to agricultural cropsTextCervus elaphus nelsoni
Crop damage
Electric fence
Elk
Mule deer
Odocoileus hemionus
Repellent
Sunflowers
Wildlife damage management
Winged fence
Type:Text
Subject:Cervus elaphus nelsoni
Crop damage
Electric fence
Elk
Mule deer
Odocoileus hemionus
Repellent
Sunflowers
Wildlife damage management
Winged fence
Description:Mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni) provide important recreational, ecological, and economic benefits, but can also cause substantial damage to agricultural crops. Cervid damage to agriculture creates challenges for wildlife agencies responsible for minimizing crop depredation while maintaining healthy deer and elk populations. Sunflower producers in southwestern Colorado, USA, have experienced high deer and elk damage and were interested in temporary methods to reduce damage that were cost-effective for rotational crops. To address this challenge, we investigated 3 temporary, non-lethal exclusion and repellent techniques for reducing deer and elk damage to sunflowers: 1) a polyrope electric fence, 2) the chemical repellent Plantskydd™, and 3) a winged fence. During July through October 2011 and 2012, we used a randomized block design to test the efficacy of these techniques by quantifying cervid damage to sunflowers and the number of deer and elk tracks traversing treatment and control plot boundaries. Using generalized linear mixed models we found that polyrope electric fences reduced deer and elk damage and presence within plots, while the repellent and winged fences did not reduce ungulate activity. Polyrope electric fences may be a suitable tool in areas where wildlife management agencies want to maintain deer and elk populations but reduce seasonal damage by cervids to high-value crops. In Colorado, use of an effective exclusion technique such as polyrope electric fence could also decrease the need for lethal depredation permits and damage compensation payments, and increase satisfaction among producers and the public. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [show more]
Interactions of Zooplankton, Mysis relicta, and Kokanees in Lake Granby, ColoradoInteractions of Zooplankton, <em>Mysis relicta</em>, and Kokanees in Lake Granby, ColoradoTextMysis relicta
Kokanee
Colorado
Habitat management
Type:Text
Subject:Mysis relicta
Kokanee
Colorado
Habitat management
Description:Abstract. In studies of zooplankton and kokanees Oncorhynchus nerka in Lake Granby, Colorado, conducted from 1981 to 1983, we investigated the suspected role of introduced Mysis relicta in the decline of the kokanee sport fishery and egg take. Mysis relicta entered surface watersat night and preyed on zooplankton, except when summer temperatures above 14°C excluded it from the epilimnion and created a temporary refuge for cladocerans. We attributed the disappearance of hypolimnetic Daphnia longiremis to predation by mysids, and the virtual elimination of Daphnia pulex (once the preferred item in the kokanee diet) to the effects of intense selective predation by abundant M. relicta and to kokanee overstocking. Daphnia galeata mendotae, historically the most abundant daphnid, has replaced D. pulex as the principal item in the kokanee diet. Premysid populations of Daphnia spp. appeared by late May and peaked by late July, whereas postmysid populations appeared in late June and peaked in late August or early September. Mysis relicta appeared more frequently in stomachs of large  kokanees ( 21)0 mm in total length) and sometimes contributed substantially to the biomass of the kokanee diet. However, actual numbers of mysids and their frequency of occurrence in individual kokanee stomachs remained low. The disappearance or persistence of Daphnia spp. in other Colorado waters containing mysids appears to be explained by thermal conditions. It is clear that the introduced M. relicta has not adequately substituted for the diminished daphnid populations that were used heavily by planktivorous fishes. [show more]
Abert's squirrel coloring pageAbert's squirrel coloring pageTextAbert's squirrel
Tassel-eared squirrel
Education
Wildlife
Type:Text
Subject:Abert's squirrel
Tassel-eared squirrel
Education
Wildlife
Description:Coloring pages for Abert's squirrel
Density estimation...Density estimation...TextAbundance
Density
Demographic closure
Sampling
Type:Text
Subject:Abundance
Density
Demographic closure
Sampling
Description:Abundance is commonly sought after as a state variable for the study of populations. However, density (number of animals per unit area) can be a more meaningful metric because it casts the state of a population into a common currency. For example, using closed capture models from Chapter 14, we estimate 500 animals at site A and 200 animals at site B. Thus one conclusion we may reach is that habitat management at site A has positively impacted the population there compared to site B. However, if we know site A is 250 hectares and B is 100 hectares, then we realize that each has 2.0 animals/hectare. That is, on a relative scale, the different management scheme at A had no effect compared to site B. Conversely, we may estimate abundance at 2 sites to be similar and conclude management actions, or habitat types, or harvest regulations, etc. are having a similar impact, but if the sites are different sizes, then the impacts are actually quite different on a relative scale and our conclusion is erroneous. Thus, while abundance can be a useful metric, estimating density can be helpful as well. [show more]