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ID: Dual Disease Resistance in Rainbowy Trout Fact Sheet
Dual Disease Resistance in Rainbowy Trout Fact Sheet
Type: 
Subjects: 
Item 

        Dual Disease Resistance in Rainbowy Trout Fact Sheet    

                                    

ID: Dual resistance to Flavobacterium psychrophilum and Myxobolus cerebralis in rainbow trout (Oncorhynchus mykiss, Walbaum)
Dual resistance to Flavobacterium psychrophilum and Myxobolus cerebralis in rainbow trout (Oncorhynchus mykiss, Walbaum)
Type: Article
Subjects: Bacterial coldwater disease
<em>Flavobacterium psychrophilum</em>
<em>Myxobolus cerebralis</em>
Rainbow trout


Whirling disease
Item 

        Dual resistance to Flavobacterium psychrophilum and Myxobolus cerebralis in rainbow trout (Oncorhynchus mykiss, Walbaum)    
Type:Article
Subject:Bacterial coldwater disease
<em>Flavobacterium psychrophilum</em>
<em>Myxobolus cerebralis</em>
Rainbow trout


Whirling disease

                    Description:Aquatic pathogens are a major concern for fish hatchery production, fisheries management, and conservation, and disease control needs to be addressed. Two important salmonid pathogens are Myxobolus cerebralis and Flavobacterium psychrophilum that cause whirling disease and bacterial coldwater disease (BCWD), respectively. Innate disease resistance is a potential option for reducing disease-related mortality in hatchery-reared rainbow trout (Oncorhynchus mykiss, Walbaum). Two experiments were conducted to assess pathogen resistance of first-generation (F1) rainbow trout created by crossing M. cerebralis- and F. psychrophilum-resistant strains. In the first experiment, we exposed two rainbow trout strains and one F1 cross to six treatments: control (no exposure), mock injection, F. psychrophilum only, M. cerebralis only, F. psychrophilum then M. cerebralis, and M. cerebralis then F. psychrophilum. Results indicated that the F1 cross was not resistant to either pathogen. In the second experiment, we exposed five rainbow trout strains and four rainbow trout crosses to F. psychrophilum. The second experiment indicated that at least one rainbow trout cross was F. psychrophilum-resistant. Achieving dual resistance may be possible using selective breeding but only some multigenerational strains are suitable candidates for further evaluation. [show more]                

ID: EBSCO Discovery Quick Guide
EBSCO Discovery Quick Guide
Type: 
Subjects: 
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        EBSCO Discovery Quick Guide    

                    Description:EBSCO Discovery Service (EDS) features at a glance.                

ID: Education, outreach, and partnerships 2020 annual report
Education, outreach, and partnerships 2020 annual report
Type: Text
Subjects: Education and interpretation
Outreach
Partnerships
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        Education, outreach, and partnerships 2020 annual report    
Type:Text
Subject:Education and interpretation
Outreach
Partnerships

                    Description:Colorado Parks and Wildlife (CPW) employs some of the most talented staff committed to inspiring future generations and connecting people to meaningful outdoor experiences. Whether it’s leading a guided hike, presenting to a local school group, teaching hunting or fishing skills, or working events with valued partners, CPW staff and volunteers continuously demonstrate their dedication to one of the most important sentiments in our mission: educate and inspire current and future generations to serve as active stewards of Colorado’s natural resources. How we accomplish this vision, along with connecting to our Strategic Goals, manifests across the state and across disciplines, in a myriad of ways. One only needs to peruse the next few pages of this report to see that. [show more]                

ID: Effectiveness of a redesigned vaginal implant transmitter in mule deer
Effectiveness of a redesigned vaginal implant transmitter in mule deer
Type: Article
Subjects: Birth site
Capture
Colorado
Fawn
Fetus
Mule deer
Neonate
<em>Odocoileus hemionus</em>
Parturition
Vaginal implant transmitter (VIT)
Item 

        Effectiveness of a redesigned vaginal implant transmitter in mule deer    
Type:Article
Subject:Birth site
Capture
Colorado
Fawn
Fetus
Mule deer
Neonate
<em>Odocoileus hemionus</em>
Parturition
Vaginal implant transmitter (VIT)

                    Description:Our understanding of factors that limit mule deer (Odocoileus hemionus) populations may be improved by evaluating neonatal survival as a function of dam characteristics under free-ranging conditions, which generally requires that both neonates and dams are radiocollared. The most viable technique facilitating capture of neonates from radiocollared adult females is use of vaginal implant transmitters (VITs). To date, VITs have allowed research opportunities that were not previously possible; however, VITs are often expelled from adult females prepartum, which limits their effectiveness. We redesigned an existing VIT manufactured by Advanced Telemetry Systems (ATS; Isanti, MN) by lengthening and widening wings used to retain the VIT in an adult female. Our objective was to increase VIT retention rates and thereby increase the likelihood of locating birth sites and newborn fawns. We placed the newly designed VITs in 59 adult female mule deer and evaluated the probability of retention to parturition and the probability of detecting newborn fawns. We also developed an equation for determining VIT sample size necessary to achieve a specified sample size of neonates. The probability of a VIT being retained until parturition was 0.766 (SE = 0.0605) and the probability of a VIT being retained to within 3 days of parturition was 0.894 (SE = 0.0441). In a similar study using the original VIT wings (Bishop et al. 2007), the probability of a VIT being retained until parturition was 0.447 (SE = 0.0468) and the probability of retention to within 3 days of parturition was 0.623 (SE = 0.0456). Thus, our design modification increased VIT retention to parturition by 0.319 (SE = 0.0765) and VIT retention to within 3 days of parturition by 0.271 (SE = 0.0634). Considering dams that retained VITs to within 3 days of parturition, the probability of detecting at least 1 neonate was 0.952 (SE = 0.0334) and the probability of detecting both fawns from twin litters was 0.588 (SE = 0.0827). We expended approximately 12 person-hours per detected neonate. As a guide for researchers planning future studies, we found that VIT sample size should approximately equal the targeted neonate sample size. Our study expands opportunities for conducting research that links adult female attributes to productivity and offspring survival in mule deer. [show more]                

ID: Effects of Brown Trout Removal on Reestablishing Populations of Rainbow Trout
Effects of Brown Trout Removal on Reestablishing Populations of Rainbow Trout
Type: 
Subjects: 
Item 

        Effects of Brown Trout Removal on Reestablishing Populations of Rainbow Trout    

                    Description:Led by:Dr. Eric R. FethermanStudy area:Gunnison River, Cache la Poudre River, and Yampa River Project status:Completed
Research Objectives
To determine the effects of brown trout removal on reestablishing populations of rainbow trout.
To improve rainbow trout retention and survival following reintroduction. ​
Project Description
Rainbow trout populations experienced significant population declines following the establishment of whirling disease to Colorado in the 1980s. Brown trout, however, evolved with the parasite that causes whirling disease in their European home range, so they developed a resistance to the disease. As a result, brown trout populations exhibited increases in many rivers across the state as they filled the open niches left behind by rainbow trout.
Fishery managers stock whirling disease resistant rainbow trout​(known as the Hofer) in many of the state's waters to supplement and recover populations lost to the disease. However, increased numbers of brown trout result in greater predation on and competition with the stocked rainbows, reducing the survival and retention of rainbow trout populations. 
As a result, CPW initiated several experiments on the Gunnison and Cache la Poudre Rivers to examine the effects of brown trout removal on fry and adult rainbow trout retention and survival following reintroduction to these rivers. 
In the Gunnison River (Gunnison Gorge National Conservation Area near Montrose, Colo.), researchers conducted two experiments. Two 1-mile sections of the river were used for the experiments. In both, brown trout fry were removed from one half of the 1-mile study section, and rainbow trout were introduced after the removal. The results from these experiments suggested that rainbow trout fry exhibited higher survival and retention rates in the sections from which brown trout fry had been removed compared to those sections in which brown trout fry had not been removed.  
The largest of the brown trout removal experiments occurred in the Cache la Poudre River, northwest of Fort Collins, Colo. The study, a cooperative research project between Colorado State University and Colorado Parks and Wildlife, was designed to determine if adult brown trout removal and relocation could be used to reestablish wild rainbow trout populations. During the experiments, researchers examined the interactions between brown trout and stocked rainbow trout, including the potential for competition, predation, emigration, survival and growth.
Movement and survival data suggest that brown trout removal and relocation had a positive short-term effect. Rainbow trout displayed higher survival and lower emigration rates in the removal section in the months following the removal. On average, rainbow trout grew 1.5 inches in the two months following their introduction. However, rainbow trout emigration and survival decreased as time went on, suggesting that brown trout removal and relocation did not increase long-term survival or retention of rainbow trout.​
CPW initiated an experiment in the Yampa River in 2017 to determine the effects of large-scale brown trout removal on wild and stocked fingerling and catchable rainbow trout survival. Brown trout removal occurred across four years and over a nearly seven mile stretch of the Yampa River between Stagecoach Reservoir and Lake Catamount. Because this is a closed system between two reservoirs and the removals occurred over a greater distance than in the Cache la Poudre River, brown trout removal appeared to be more effective at reducing the number of brown trout adults in the system, and thereby competition and predation on wild and stocked rainbow trout. Results are pending, but preliminary estimates suggest that both rainbow trout retention and survival increased in the Yampa River as a result of the brown trout removals.
CPW will continue to conduct research on the interactions between brown trout and rainbow trout. Using this research, CPW hopes to reestablish rainbow trout populations in Colorado's rivers. ​
Associated Publications
Fetherman, E. R., D. L. Winkelman, L. L. Bailey, G. J. Schisler, and K. Davies. 2015. Brown trout removal effects on short-term survival and movement of Myxobolus cerebralis­­-resistant rainbow trout. Transactions of the American Fisheries Society 144:610-626.​
Fetherman, E. R., and G. J. Schisler. 2013. Sport Fish Research Studies. Federal Aid Project F394-R12. Federal Aid in Fish Restoration Job Progress Report. Colorado Parks and Wildlife. Aquatic Research Section. Fort Collins, CO. 132.Read an overview of Colorado's research on whirling disease in the Whirling Disease Fact Sheet.
 [show more]                

ID: Effects of Habitat Treatments on Mule Deer Survival and Health During the Winter
Effects of Habitat Treatments on Mule Deer Survival and Health During the Winter
Type: 
Subjects: 
Item 

        Effects of Habitat Treatments on Mule Deer Survival and Health During the Winter    

                    Description:Led By: Eric BergmanStudy Area: Uncompahgre Plateau and adjacent valleys in southwest Colorado Project Status: Completed Research Objectives:To evaluate the impacts of large-scale vegetation habitat treatment on mule deer survival and health during the winter.
To develop habitat management strategies for the benefit of deer
To put research results into context with historical records and recent declines in mule deer herd populations.
Project Description: Mule deer populations in Colorado have shown dramatic fluctuations since the 1960s. Beginning in the 1990s, some western Colorado mule deer herds demonstrated the most recent decline. For many decades, wildlife managers have used habitat management as a way to increase the health and survival of mule deer, but the effect of these efforts had not yet been evaluated. Evaluating these efforts was the focus of this 4-year study to measure the health and survival of mule deer herds during the winter months in areas treated with different levels of habitat management. In the course of this study, researchers monitored fawn survival, mule deer body conditions, and population densities in areas with different levels of habitat management. Habitat treatment varied from mechanical disturbance in the form of hydro-axe clearing and roller-chopping of late seral stage pinyon-juniper forests, chemical control of weeds, and reseeding with desirable mule deer browse species. The results of this study will help managers select the most effective habitat treatments to apply to mule deer winter ranges. Associated PublicationsBergman, E.J., C.J. Bishop, D.J. Freddy, G.C. White and P.F. Doherty. 2014. Habitat management influence overwinter survival of mule deer fawns in Colorado. Journal of Wildlife Management 78(3):448–455.
Bergman, E.J. 2013. Evaluation of winter range habitat treatments on overwinter survival, density, and body condition of mule deer. Dissertation, Colorado State University, Fort Collins, Colorado, USA, 137pp.
Watkins, B.E., C.J. Bishop, E.J. Bergman, B. Hale, B.F. Wakeling, A. Bronson, L.H. Carpenter, and D.W. Lutz.  2007. Habitat guidelines for mule deer: Colorado Plateau shrubland and forest ecoregion. Mule Deer Working Group, Western Association of Fish and Wildlife Agencies, Cheyenne, Wyoming, USA. 72pp.
Bergman, E.J., P.F. Doherty, G.C. White, and D.J. Freddy. 2014. Habitat and herbivore density: response of mule deer to habitat management. The Journal of Wildlife Management 79:60–68.
Bergman, E.J., P.F. Doherty, G.C. White, and A.A. Holland. 2015. Density dependence in mule deer: a review of evidence. Wildlife Biology 21:18–29.
Bergman, E.J., P.F. Doherty,  C.J. Bishop, L.L. Wolfe, and B. Banulis. 2014. Herbivore body condition response in altered environments: mule deer and habitat management. PloS one 9: e106374.
ResourcesWest Slope Mule Deer Strategy [show more]                

ID: Effects of helicopter capture and handling on movement behavior of mule deer
Effects of helicopter capture and handling on movement behavior of mule deer
Type: Article
Subjects: Animal handling
Animal movement
Capture effects
Colorado
GPS radio collar
Helicopter net gunning
Live capture
Mule deer
<em>Odocoileus hemionus</em>
Item 

        Effects of helicopter capture and handling on movement behavior of mule deer    
Type:Article
Subject:Animal handling
Animal movement
Capture effects
Colorado
GPS radio collar
Helicopter net gunning
Live capture
Mule deer
<em>Odocoileus hemionus</em>

                    Description:Research on wildlife movement, physiology, and reproductive biology often requires capture and handling of animals. Such invasive treatment can alter behavior, which may bias results or invalidate assumptions regarding representative behaviors. To assess the impacts of handling on mule deer (Odocoileus hemionus), a focal species for research in North America, we investigated pre- and post-recapture movements of collared individuals, and compared them to deer that were not recaptured (controls). We compared pre- and post-recapture movement rates (m/hr) and 24-hour straight-line displacement among recaptured and control deer. In addition, we examined the time it took recaptured deer to return to their pre-recapture home range. Both daily straight-line displacement and movement rate were marginally elevated relative to monthly averages for 24 hours following recapture, with non-significant elevation continuing for up to 7 days. Comparing movements averaged over 30 days before and after recapture, we found no differences in displacement, but movement rates demonstrated seasonal effects, with faster movements post- relative to pre-recapture in March and slower movements post- relative to pre-recapture in December. Relative to control deer movements, recaptured deer movement rates in March were higher immediately after recapture and lower in the second and third weeks following recapture. The median time to return to the pre-recapture home range was 13 hours, with 71% of deer returning in the first day, and 91% returning within 4 days. These results indicate a short period of elevated movements following recaptures, likely due to the deer returning to their home ranges, followed by weaker but non-significant depression of movements for up to 3 weeks. Censoring of the first day of data post-capture from analyses is strongly supported, and removing additional days until the individual returns to its home range will control for the majority of impacts from capture. [show more]                

ID: Effects of male-biased harvest on mule deer: Implications for rates of pregnancy, synchrony, and timing of parturition
Effects of male-biased harvest on mule deer: Implications for rates of pregnancy, synchrony, and timing of parturition
Type: Article
Subjects: Male/female ratio
Mule deer
<em>Odocoileus hemionus</em>
Rates of pregnancy
Sex ratio
Synchrony
Timing of parturition
Ungulate management
Item 

        Effects of male-biased harvest on mule deer: Implications for rates of pregnancy, synchrony, and timing of parturition    
Type:Article
Subject:Male/female ratio
Mule deer
<em>Odocoileus hemionus</em>
Rates of pregnancy
Sex ratio
Synchrony
Timing of parturition
Ungulate management

                    Description:Evaluating how management practices influence the population dynamics of ungulates may enhance future management of these species. For example, in mule deer (Odocoileus hemionus), changes in male/female ratio due to male-biased harvest may alter rates of pregnancy, timing of parturition, and synchrony of parturition if inadequate numbers of males are present to fertilize females during their first estrous cycle. If rates of pregnancy or parturition are influenced by decreased male/female ratios, recruitment may be reduced (e.g., fewer births, later parturition resulting in lower survival of fawns, and a less synchronous parturition that potentially increases susceptibility of neonates to predation). Our objectives were to compare rates of pregnancy, synchrony of parturition, and timing of parturition between exploited mule deer populations with a relatively high (Piceance, CO, USA; 26 males/100 females) and a relatively low (Monroe, UT, USA; 14 males/100 females) male/female ratio. We determined rates of pregnancy via ultrasonography and timing of parturition via vaginal implant transmitters. We found no differences in rates of pregnancy (98.6% and 96.6%; z = −0.821; P = 0.794), timing of parturition (estimate = 1.258; SE = 1.672; t = 0.752; P = 0.454), or synchrony of parturition (F = 1.073 P = 0.859) between Monroe Mountain and Piceance Basin, respectively. The relatively low male/female ratio on Monroe Mountain was not associated with a protracted period of parturition. This finding suggests that relatively low male/female ratios typical of heavily harvested populations do not influence population dynamics because recruitment remains unaffected. [show more]                

ID: Effects of willow nutrition and morphology on calving success of moose
Effects of willow nutrition and morphology on calving success of moose
Type: Article
Subjects: Alces alces
Calving success
Colorado
Moose, nutrition
Reproduction
Salix
Willow
Item 

        Effects of willow nutrition and morphology on calving success of moose    
Type:Article
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]                