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ID: Developing Cost-Effective Strategies for Managing Moose in Colorado
Developing Cost-Effective Strategies for Managing Moose in Colorado
Type: 
Subjects: 
Item 

        Developing Cost-Effective Strategies for Managing Moose in Colorado    

                    Description:Led ByEric Bergman
Study AreaNorthwest Colorado (Rabbit Ears mountain range); Northeast Colorado (Laramie River drainage); Southwest Colorado (Upper portions of the Rio Grande River and near Lake City)
Project StatusCompleted
Research Objectives
To develop alternative cost-effective strategies for harvest and management of moose populations.
To incorporate moose life-history characteristics into management plans.
To compare moose survival rates across the state.
To collect data on moose disease and health.
Project Description
With limited budgets, wildlife managers must often prioritize management funding based on details such as:
​Species abundance​​
The a​mount of revenue generated by a species
The endangered or threatened status of a species
Moose are less abundant in Colorado than elk and deer, thus funding for moose management tends to be lower in comparison. In addition, moose populations are more difficult to estimate because most of Colorado's moose herds live in forests, making aerial observation difficult. As a result, reliable moose population data are limited. Without these data, wildlife managers cannot make fully informed licensing decisions. 
Fortunately, other factors besides population abundance can inform wildlife managers about moose population status. For example, reduced pregnancy and survival rates can indicate low food availability due to increased herd sizes. Using these other factors, researchers will develop population models that wildlife managers can use to manage moose populations in the state.Related Publications:Bergman, Eric J. 2013-2022. Evaluation and incorporation of life history traits, nutritional status, and browse characteristics in Shira's moose management in Colorado. (Annual federal aid progress reports combined into one document)
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ID: Development of distribution models for management of greater sage-grouse in North Park Colorado
Development of distribution models for management of greater sage-grouse in North Park Colorado
Type: Text
Subjects: Greater sage-grouse
<em>Centrocercus urophasianus</em>
Wildlife management
Item 

        Development of distribution models for management of greater sage-grouse in North Park Colorado    
Type:Text
Subject:Greater sage-grouse
<em>Centrocercus urophasianus</em>
Wildlife management

                    Description:Rangewide declines of greater sage-grouse and recent energy development within sagebrush habitat has led to concern for conservation of greater sage-grouse (Centrocercus urophasianus) (GRSG) populations across Colorado, including in North Park, which supports approximately 20% of the state’s GRSG. Seasonal variations in habitat use by GRSG can provide important information for biologists and managers on the ground. These habitats have been mapped at the statewide level at a large scale, but have not been completed specifically for the North Park population. Investigating the smaller scale seasonal habitat selection of GRSG in North Park is important as no data from North Park was used in the statewide analysis. Since GRSG habitat use is known to be influenced by both landscape-scale and local-scale factors, data specific to North Park can be used to refine the statewide models at a more local scale. [show more]                

ID: Development of landscape scale resource selection models for the management of Gunnison sage-grouse in the Gunnison Basin population
Development of landscape scale resource selection models for the management of Gunnison sage-grouse in the Gunnison Basin population
Type: Text
Subjects: Gunnison sage-grouse
<em>Centrocercus minimus</em>
Wildlife management
Item 

        Development of landscape scale resource selection models for the management of Gunnison sage-grouse in the Gunnison Basin population    
Type:Text
Subject:Gunnison sage-grouse
<em>Centrocercus minimus</em>
Wildlife management

                    Description:Gunnison sage-grouse (Centrocercus minimus) have declined substantially from their historica range and were listed as threatened by the U. S. Fish and Wildlife Service in November of 2014. GUSG are distributed into seven isolated populations in Colorado and one population, Gunnison Basin (GB) comprises 85-09% of all GUSG in the state. Concern over the small population size and isolated and fragmented nature of many of the smaller populations has led to interest in the habitat use of GUSG. Much of the information that has been used on GUSG habitat selection has come from studies pertaining to Greater Sage-grouse. Currently the USFWS have designated most of the Gunnison basin as critical habitat, but there may be some variability to the quality and use of that critical habitat which could refine those maps for better management of the species. To successfully manage and understand the Gunnison sage-grouse, we must identify the habitat that is most important to the birds using data driven models. Colorado Parks and Wildlife has collected radio-telemetry data from almost 200 birds from 2004-2010 which could be used to model habitat selection with a robust dataset specific to the Gunnison sage-grouse in the Gunnison basin. [show more]                

ID: Development of landscape scale resource selection models using interpolated layers from micro-scale vegetation measurements in North Park, Colorado
Development of landscape scale resource selection models using interpolated layers from micro-scale vegetation measurements in North Park, Colorado
Type: Text
Subjects: Wildlife management
Wildlife habitat improvement
Item 

        Development of landscape scale resource selection models using interpolated layers from micro-scale vegetation measurements in North Park, Colorado    
Type:Text
Subject:Wildlife management
Wildlife habitat improvement

                    Description:State agencies have long used micro-scale vegetation measurements to assess relationships between species and how they chose their habitat. Often species select small scale habitat based on vegetation structure, the height and density of certain vegetation, and the availability of forage species. With the onset of remote sensing and the ability to predict species’ distributions based on relatively easy and inexpensive methods, micro-scale measurements have had reduced value when describing a species’ habitat selection. There is also the problem of how to translate micro-scale measurements at a small scale to landscape level resource selection models. There is a long history of using interpolation methods to predict vegetation characteristics across space, but these predictive surfaces have rarely been applied to spatial models of species habitat. [show more]                

ID: Differential impacts of spruce beetle outbreaks on snowshoe hares and red squirrels in the southern Rocky Mountains
Differential impacts of spruce beetle outbreaks on snowshoe hares and red squirrels in the southern Rocky Mountains
Type: Article
Subjects: Colorado
<em>Dendroctonus rufipennis</em>
Density
<em>Lepus americanus</em>
<em>Tamiasciurus hudsonicus</em>
Spruce beetle
Snowshoe hare
American red squirrel
Distance sampling
Item 

        Differential impacts of spruce beetle outbreaks on snowshoe hares and red squirrels in the southern Rocky Mountains    
Type:Article
Subject:Colorado
<em>Dendroctonus rufipennis</em>
Density
<em>Lepus americanus</em>
<em>Tamiasciurus hudsonicus</em>
Spruce beetle
Snowshoe hare
American red squirrel
Distance sampling

                    Description:Spruce beetles (Dendroctonus rufipennis) have impacted millions of acres of Engelmann spruce (Picea engelmannii) – subalpine fir (Abies lasiocarpa) forest in North America over the past decade, resulting in the most extensive outbreak in recorded history. This dramatic alteration of forest composition and structure has precipitated numerous changes to forest ecology and ecosystem services. Among the least studied of these changes are impacts to wild mammals, including snowshoe hares (Lepus americanus) and red squirrels (Tamiasciurus hudsonicus). We sampled a chronosequence of spruce-fir stands along a gradient of ‘years elapsed since spruce beetle outbreak’ (YSO) in order to estimate impacts to abundance of these two species in the southern Rocky Mountains. Snowshoe hare abundance was not related to YSO, at least in the first decade post-outbreak. Instead, hare abundance during this period was positively related to horizontal cover, especially that due to stem density of small diameter subalpine fir. Notably, snowshoe hare abundance was negatively related to stem density of small diameter Engelmann spruce, suggesting that elements of horizontal cover may not be uniformly beneficial to hares. Hare abundance was also negatively related to ground cover, which could help explain the lack of relationship to YSO, assuming reduction in overstory canopy would lead to increases in ground cover. Red squirrel abundance was negatively related to YSO and outbreak severity (i.e., basal area of large diameter dead trees). This was likely due to diminished cone crops in impacted areas, which red squirrels cache and rely on heavily to sustain them through the winter. Basal area of remaining large live fir trees was not related to squirrel abundance, suggesting that regeneration of spruce and associated cone crops may be necessary for recovery of red squirrels, which may take several decades. [show more]                

ID: Diseases at Feeders
Diseases at Feeders
Type: Fact Sheet
Subjects: Birds -- Diseases
Bird feeders
Salmonella infections
Trichomoniasis
Conjunctivitis
Trichomoniasis
Item 

        Diseases at Feeders    
Type:Fact Sheet
Subject:Birds -- Diseases
Bird feeders
Salmonella infections
Trichomoniasis
Conjunctivitis
Trichomoniasis

                    Description:Fact sheet: Many diseases are spread at bird feeders including salmonellosis, trichomoniasis, finch conjunctivitis, avian pox, and others.                

ID: Div report 4 cover
Div report 4 cover
Type: 
Subjects: 
Item 

        Div report 4 cover    

                                    

ID: Diverse university students across the United States reveal promising pathways to hunter recruitment and retention
Diverse university students across the United States reveal promising pathways to hunter recruitment and retention
Type: Article
Subjects: Decision-making
Forest landowners
Behavior change model
Landowner behavior
Item 

        Diverse university students across the United States reveal promising pathways to hunter recruitment and retention    
Type:Article
Subject:Decision-making
Forest landowners
Behavior change model
Landowner behavior

                    Description:Declining participation in hunting, especially among young adult hunters, affects the ability of state and federal agencies to achieve goals for wildlife management and decreases revenue for conservation. For wildlife agencies hoping to engage diverse audiences in hunter recruitment, retention, and reactivation (R3) efforts, university settings provide unique advantages: they contain millions of young adults who are developmentally primed to explore new activities, and they cultivate a social atmosphere where new identities can flourish. From 2018 to 2020, we surveyed 17,203 undergraduate students at public universities across 22 states in the United States to explore R3 potential on college campuses and assess key demographic, social, and cognitive correlates of past and intended future hunting behavior. After weighting to account for demographic differences between our sample and the larger student population, 29% of students across all states had hunted in the past. Students with previous hunting experience were likely to be white, male, from rural areas or hunting families, and pursuing degrees related to natural resources. When we grouped students into 1 of 4 categories with respect to hunting (i.e., non-hunters [50%], potential hunters [22%], active hunters [26%], and lapsed hunters [3%]), comparisons revealed differences based on demographic attributes, beliefs, attitudes, and behaviors. Compared to active hunters, potential hunters were more likely to be females or racial and ethnic minorities, and less likely to experience social support for hunting. Potential hunters valued game meat and altruistic reasons for hunting, but they faced unique constraints due to lack of hunting knowledge and skills. Findings provide insights for marketing and programming designed to achieve R3 objectives with a focus on university students. [show more]                

ID: Does a population of cougars exist in Michigan?
Does a population of cougars exist in Michigan?
Type: Article
Subjects: Cougar
Michigan
DNA
Distribution
Item 

        Does a population of cougars exist in Michigan?    
Type:Article
Subject:Cougar
Michigan
DNA
Distribution

                    Description:After analyzing DNA obtained from fecal samples gathered in Michigan,  href="https://bioone.org/journals/the-american-midland-naturalist/volume-158/issue-2/0003-0031(2007)158%5B467%3ADAPOCE%5D2.0.CO%3B2/Does-a-Population-of-Cougars-Exist-in-Michigan/10.1674/0003-0031(2007)158%5B467:DAPOCE%5D2.0.CO;2.short#i0003-0031-158-2-467-Swanson1">Swanson and Rusz (2006) claimed that 83% of identified scats were from cougars, indicating to them that a population of these large carnivores existed in the state. In this paper, we identify problems with their methodology, suggest that they unreasonably extrapolated their conclusions and point out that their results are improbable, especially in light of no other evidence in the scientific literature suggesting the existence of a population of cougars in Michigan. [show more]                

ID: Dr. George J. Schisler
Dr. George J. Schisler
Type: 
Subjects: 
Item 

        Dr. George J. Schisler    

                    Description:Aquatic Research Section LeaderContact Information

Colorado Parks and Wildlife317 West Prospect StreetFort Collins, CO 80526Phone: (970) 472-4361Fax: (970) 472-4457Email:  href="mailto:[email protected]">[email protected]Google Scholar Profile​
ResearchGate Profile​
Education
Ph.D., Fishery and Wildlife Biology — Colorado State University, 1999
M.S., Fishery and Wildlife Biology — Colorado State University, 1995
B.S., Biology and Fishery Science — University of Alaska, 1992
Current or Recent Positions
Aquatic Research Chief — Colorado Parks and Wildlife, 2011-Present
Aquatic Research Scientist — Colorado Parks and Wildlife, 2001-2011
Post-Doctorate Fellow — Colorado State University, 1999-2000
Research Associate — Colorado Cooperative Fish and Wildlife Research Unit, 1993-1999
Current or Recent Research Projects
Directs statewide aquatic research activities involving all aspects of native and non-native aquatic wildlife. Supervises a staff of 14 research scientists, hatchery technicians, and support staff. Ongoing research studies include evaluations of various strains of whirling disease resistant rainbow trout for hatchery production re-establishment in the wild.   
Areas of Interest/Expertise
My research interest areas include salmonid reproduction and strain selection, salmonid disease studies, the economic impacts of fisheries in Colorado, and angler creel and mail-in surveys. 
Publications
Erickson, T.A., G.J. Schisler, and E.R. Fetherman. 2023. Poststocking survival and myxospore evaluation of whirling disease‐resistant rainbow trout strains. North American Journal of Fisheries Management. 43(2):586-599.
Americus, B., G. J. Schisler,  J.L. Bartholomew, and S.D. Atkinson. 2021. Myxobolus cerebralis causes presporogonic mortality in juvenile mountain whitefish. Journal of Aquatic Animal Health. 33(2):116-122.

Nehring, G. J. Schisler, L. Chiaramonte, A. Horton, and B. Poole. 2016. Accelerated deactivation of Myxobolus cerebralis myxospores by susceptible and non-susceptible Tubifex tubifex. Diseases of Aquatic Organisms. 121(1):37-47.
Purdy, P., E.A. Barbosa, C. J. Praamsma, and G. J. Schisler. 2016. Modification of trout sperm membranes associated with activation and cryopreservation. Implications for fertilizing potential. Cryobiology 73(1):73-79.
Nehring, R. B., G. Schisler, L. Chiaramonte, A. Horton, and B. Poole. 2015. Assessment of the long-term viability of the myxospores of Myxobolus cerebralis as determined by production of the actinospores by Tubifex tubifex. Journal of Aquatic Animal Health. 27(1):50-56.
​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., D. L. Winkelman, M. R. Baerwald, and G. J. Schisler. 2014. Survival and reproduction of Myxobolus cerebralis resistant rainbow trout in the Colorado River and increased survival of age-0 progeny. PLoS ONE. 9(5):e96954.
​Fetherman, E.R., D. L. Winkelman, G. J. Schisler, and M. F. Antolin. 2012. Genetic basis of differences in myxospore count between whirling disease-resistant and –susceptible strains of rainbow trout. Diseases of Aquatic Organisms. 102:97-106.
Baerwald, M. R., Petersen, J. L., Hedrick, R. P., Schisler, G. J., and B. May. 2011. A major effect quantitative trait locus for whirling disease resistance identified in rainbow trout Oncorhynchus mykiss. Heredity. 106:920-926.
Fetherman, E. R., D. L. Winkelman, G. J. Schisler, and C. A. Myrick. 2011. The effects of Myxobolus cerebralis on the physiological performance of whirling disease resistant and susceptible strains of rainbow trout. Journal of Aquatic Animal Health. 23:169-177.
Schisler, G. J., N. K. M. Vieira, and P. G. Walker. 2008. Application of Household Disinfectants to Control New Zealand Mudsnails. North American Journal of Fisheries Management. 28:1172–1176.
Schisler, G. J., K. A. Myklebust, and R. P. Hedrick. 2006. Inheritance of Myxobolus cerebralis resistance among F1-generation crosses of whirling disease resistant and susceptible rainbow trout strains. Journal of Aquatic Animal Health. 18:109–115.
Schisler, G. J., and E. P. Bergersen. 2002. Evaluation of risk of high elevation Colorado waters to the establishment of Myxobolus cerebralis​. Pages 33-41 in J. L. Bartholomew and J. C. Wilson, editors. Whirling disease: reviews and current topics. American Fisheries Society, Symposium 29, Bethesda, Maryland.
Schisler, G. J., E. P. Bergersen, P. G. Walker, J. Wood, and J. K. Epp. 2001. C​omparison of single-round polymerase chain reaction (PCR) and pepsin-trypsin digest (PTD) methods for detection of Myxobolus cerebralis. Diseases of Aquatic Organisms. 45:109-114.
Schisler, G. J. and E. P. Bergersen. 2000. Effects of multiple stressors on morbidity and mortality of fingerling rainbow trout infected with Myxobolus cerebralis. Transactions of the American Fisheries Society. 129:859-865.
Schisler, G. J., E. P. Bergersen, and P. G. Walker. 1999. Evaluation of chronic gas supersaturation on growth, morbidity, and mortality of fingerling rainbow trout infected with Myxobolus cerebralis. North American Journal of Aquaculture. 61:175- 183.
Schisler, G. J., P. G. Walker, L. A. Chittum, and E. P. Bergersen. 1999. Gill ectoparasites of juvenile rainbow trout in the Upper Colorado River. Journal of Aquatic Animal Health. 11:170-174.
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