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Type:Article
Subject:Animal movement
Kullback–Leibler
Telemetry data
Description:A common population characteristic of interest in animal ecology studies pertains to the selection of resources. That is, given the resources available to animals, what do they ultimately choose to use? A variety of statistical approaches have been employed to examine this question and each has advantages and disadvantages with respect to the form of available data and the properties of estimators given model assumptions. A wealth of high resolution telemetry data are now being collected to study animal population movement and space use and these data present both challenges and opportunities for statistical inference. We summarize traditional methods for resource selection and then describe several extensions to deal with measurement uncertainty and an explicit movement process that exists in studies involving high-resolution telemetry data. Our approach uses a correlated random walk movement model to obtain temporally varying use and availability distributions that are employed in a weighted distribution context to estimate selection coefficients. The temporally varying coefficients are then weighted by their contribution to selection and combined to provide inference at the population level. The result is an intuitive and accessible statistical procedure that uses readily available software and is computationally feasible for large datasets. These methods are demonstrated using data collected as part of a large-scale mountain lion monitoring study in Colorado, USA. [show more]
Type: Article
Subjects: Animal movement
Hierarchical model
Individual variation
Population-level
Predation
Telemetry
Wildland-urban interface
Type:Article
Subject:Animal movement
Hierarchical model
Individual variation
Population-level
Predation
Telemetry
Wildland-urban interface
Description:

Background

While many species have suffered from the detrimental impacts of increasing human population growth, some species, such as cougars (Puma concolor), have been observed using human-modified landscapes. However, human-modified habitat can be a source of both increased risk and increased food availability, particularly for large carnivores. Assessing preferential use of the landscape is important for managing wildlife and can be particularly useful in transitional habitats, such as at the wildland-urban interface. Preferential use is often evaluated using resource selection functions (RSFs), which are focused on quantifying habitat preference using either a temporally static framework or researcher-defined temporal delineations. Many applications of RSFs do not incorporate time-varying landscape availability or temporally-varying behavior, which may mask conflict and avoidance behavior.

Methods

Contemporary approaches to incorporate landscape availability into the assessment of habitat selection include spatio-temporal point process models, step selection functions, and continuous-time Markov chain (CTMC) models; in contrast with the other methods, the CTMC model allows for explicit inference on animal movement in continuous-time. We used a hierarchical version of the CTMC framework to model speed and directionality of fine-scale movement by a population of cougars inhabiting the Front Range of Colorado, U.S.A., an area exhibiting rapid population growth and increased recreational use, as a function of individual variation and time-varying responses to landscape covariates.

Results

We found evidence for individual- and daily temporal-variability in cougar response to landscape characteristics. Distance to nearest kill site emerged as the most important driver of movement at a population-level. We also detected seasonal differences in average response to elevation, heat loading, and distance to roads. Motility was also a function of amount of development, with cougars moving faster in developed areas than in undeveloped areas.

Conclusions

The time-varying framework allowed us to detect temporal variability that would be masked in a generalized linear model, and improved the within-sample predictive ability of the model. The high degree of individual variation suggests that, if agencies want to minimize human-wildlife conflict management options should be varied and flexible. However, due to the effect of recursive behavior on cougar movement, likely related to the location and timing of potential kill-sites, kill-site identification tools may be useful for identifying areas of potential conflict.

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Type:Article
Subject:Anthropogenic disturbance
Canada lynx
Ski resorts
Snowmobiles
Space use
Winter recreation
Description:Winter recreation is a widely popular activity and is expected to increase due to changes in recreation technology and human population growth. Wildlife are frequently negatively impacted by winter recreation, however, through displacement from habitat, alteration of activity patterns, or changes in movement behavior. We studied impacts of dispersed and developed winter recreation on Canada lynx (Lynx canadensis) at their southwestern range periphery in Colorado, USA. We used GPS collars to track movements of 18 adult lynx over 4 years, coupled with GPS devices that logged 2,839 unique recreation tracks to provide a detailed spatial estimate of recreation intensity. We assessed changes in lynx spatial and temporal patterns in response to motorized and nonmotorized recreation, as well as differences in movement rate and path tortuosity. We found that lynx decreased their movement rate in areas with high-intensity back-country skiing and snowmobiling, and adjusted their temporal patterns so that they were more active at night in areas with high-intensity recreation. We did not find consistent evidence of spatial avoidance of recreation: lynx exhibited some avoidance of areas with motorized recreation, but selected areas in close proximity to nonmotorized recreation trails. Lynx appeared to avoid high-intensity developed ski resorts, however, especially when recreation was most intense. We conclude that lynx in our study areas did not exhibit strong negative responses to dispersed recreation, but instead altered their behavior and temporal patterns in a nuanced response to recreation, perhaps to decrease direct interactions with recreationists. However, based on observed avoidance of developed recreation, there may be a threshold of human disturbance above which lynx cannot coexist with winter recreation. [show more]
Type: Article
Subjects: Anthropogenic disturbances
Behavior
Colorado
Intermountain West
Mule deer
Natural-gas development

<em>Odocoileus hemionus</em>
Resource selection
Spring migration
Type:Article
Subject:Anthropogenic disturbances
Behavior
Colorado
Intermountain West
Mule deer
Natural-gas development

<em>Odocoileus hemionus</em>
Resource selection
Spring migration
Description:The disruption of traditional migratory routes by anthropogenic disturbances has shifted patterns of resource selection by many species, and in some instances has caused populations to decline. Moreover, in recent decades populations of mule deer (Odocoileus hemionus) have declined throughout much of their historic range in the western United States. We used resource-selection functions to determine if the presence of natural-gas development altered patterns of resource selection by migrating mule deer. We compared spring migration routes of adult female mule deer fitted with GPS collars (n = 167) among four study areas that had varying degrees of natural-gas development from 2008 to 2010 in the Piceance Basin of northwest Colorado, USA. Mule deer migrating through the most developed area had longer step lengths (straight-line distance between successive GPS locations) compared with deer in less-developed areas. Additionally, deer migrating through the most developed study areas tended to select for habitat types that provided greater amounts of concealment cover, whereas deer from the least developed areas tended to select habitats that increased access to forage and cover. Deer selected habitats closer to well pads and avoided roads in all instances except along the most highly developed migratory routes, where road densities may have been too high for deer to avoid roads without deviating substantially from established migration routes. These results indicate that behavioral tendencies toward avoidance of anthropogenic disturbance can be overridden during migration by the strong fidelity ungulates demonstrate towards migration routes. If avoidance is feasible, then deer may select areas further from development, whereas in highly developed areas, deer may simply increase their rate of travel along established migration routes. [show more]
Type: Article
Subjects: Anthropogenic disturbances
Colorado
Mule deer
Natural gas development
<em>Odocoileus hemionus</em>
Population dynamics
Predation
Survival
Type:Article
Subject:Anthropogenic disturbances
Colorado
Mule deer
Natural gas development
<em>Odocoileus hemionus</em>
Population dynamics
Predation
Survival
Description:Recent natural gas development has caused concern among wildlife managers, researchers, and stakeholders over the potential effects on wildlife and their habitats. Specifically, understanding how this development and other factors influence mule deer (Odocoileus hemionus) fawn (i.e., 0–6 months old) mortality rates, recruitment, and subsequently population dynamics have been identified as knowledge gaps. Thus, we tested predictions concerning the relationship between natural gas development, adult female, fawn birth, and temporal (weather) characteristics on fawn mortality in the Piceance Basin of northwestern Colorado, USA, from 2012–2014. We captured and radio-collared 184 fawns and estimated apparent cause-specific mortality in areas with relatively high or low levels of natural gas development using a multi-state model. Mean daily predation probability was similar in the high versus low development areas. Predation was the leading cause of fawn mortality in both areas and decreased from 0–14 days old. Black bear (Ursus americanus; 22% of all mortalities, n = 17) and cougar (Felis concolor; 36% of all mortalities, n = 6) predation was the leading cause of mortality in the high and low development areas, respectively. Predation of fawns was negatively correlated with the distance from a female's core area to a producing well pad on winter or summer range. Contrary to expectations, predation of fawns was positively correlated with rump fat thickness of adult females. Well pad densities and development activity were relatively low during our study, indicating that the observed intensity of development did not appear to influence daily predation probability. Our results suggest maintaining development activity thresholds at levels we observed to potentially minimize the effects of development on fawn mortality. However, we caution that higher development intensity and drilling activity in flatter, less rugged areas with less concealment cover could influence fawn mortality. Managers should maintain low development densities in areas where topography and vegetation offer less concealment. Overall, region-specific data (e.g., development intensity, topography, predator assemblages, and associated predation risk) are needed to better understand the effects of natural gas development on fawn mortality. [show more]
Type: Fact Sheet
Subjects: Aquatic animals -- Effect of water pollution on -- Colorado
Metals -- Toxicology -- Colorado
Type:Fact Sheet
Subject:Aquatic animals -- Effect of water pollution on -- Colorado
Metals -- Toxicology -- Colorado
Description:Experiments conducted by Colorado Parks and Wildlife suggest the current water quality standard for iron (Fe) is two to four times higher than it should be to protect Colorado's aquatic life.
Type: Brochure
Subjects: Aquatic invasive species
AIS
Boating
Inspection
Type:Brochure
Subject:Aquatic invasive species
AIS
Boating
Inspection
Description:The better prepared you and your boat are for an inspection, the faster it will go!
Type:Text
Subject:Aquatic nuisance species

ANS
Boating
Inspections
Zebra mussels
Quagga mussels
Description:The State of Colorado has implemented a partnership based, multi-jurisdictional, mandatory watercraft inspection and decontamination program to prevent the spread of Aquatic Nuisance Species (ANS). The purpose of the State of Colorado Containment Manual for Watercraft Inspection and Decontamination Stations (Manual) is to provide standard containment protocols across jurisdictions within Colorado, and potentially across the West. This Manual details the watercraft inspection and decontamination (WID) containment procedures to contain and prevent the overland spread of aquatic nuisance species. These procedures apply to all aquatic nuisance species, both plant and animal, but are strongly focused on zebra and quagga mussels (ZQM). [show more]
Type: Text
Subjects: Aquatic nuisance species

ANS
Fishing
Type:Text
Subject:Aquatic nuisance species

ANS
Fishing
Description:Aquatic Nuisance Species (ANS) are a significant and rapidly growing threat to Colorado’s water supply and to boating and fishing recreation. ANS are invasive animals, plants, and disease-causing pathogens that are “out of place” in Colorado’s rivers, lakes, streams, and wetlands. They are introduced accidentally or intentionally outside of their native range. Because they are not native to Colorado habitats, they have no natural competitors and predators. Without these checks and balances, the invaders are able to reproduce rapidly and out-compete native species for space and nutrients. ANS have harmful effects on natural resources, water supply systems and recreational opportunities. Once introduced, most invasive species cannot be eradicated and cost millions of dollars to manage. Preventing the introduction and spread of ANS is critical! [show more]
Type: Text
Subjects: Aquatic nuisance species

ANS
Fishing
Type:Text
Subject:Aquatic nuisance species

ANS
Fishing
Description:Live aquatic bait, such as minnows, crayfish, leeches, and mud puppies, can ruin fishing and introduce diseases to the fish already in the lake. Mussels and their microscopic larvae or plants can be transported in water held in the bait buckets or live wells. Once the boat is transported to another body of water, the Aquatic Nuisance Species (ANS) can be deposited into the new water. Anglers and boaters must take care not to move plants, animals, or water to a new lake or stream. [show more]