Policy News

Details on Colorado Proposition 127: Prohibit Bobcat, Lynx, and Mountain Lion Hunting

Colorado Ballot Initiative #91 full text

Colorado Proposition 127, November 2024  summary and analysis 

 

Select Abstracts from Recent Publications

 

Public perspectives on hunting mountain lions and black bears in Colorado

B Ghasemi, R Niemiec, and KR Crooks. 2024. Conservation Science and Practice. Wiley Online Library

Abstract - Regulated hunting of large carnivores as a management tool is a contentious topic. We report the results of two public mail‐back surveys conducted using stratified random sampling to assess Colorado residents' opinions about hunting mountain lions (ML; n = 462) and black bears (BB; n = 458). After weighting the samples to be representative of state population demographics (i.e., age, gender, level of urbanization, geographical region, and hunting participation), we found that the approval of legal and regulated hunting of MLs and BBs was polarized and varied among stakeholder groups and hunting purposes. Most residents, to varying extents, disapproved of hunting for trophy (ML 77.9%; BB 85.6%), hide or fur (80.6%; 75.2%), and recreation (62.7%; 67.0%). Over three‐fourths disapproved of hunting MLs with dogs (88.2%) and electronic calls (75.2%). Moreover, hierarchical regression results revealed that men, hunters, and those who identified as Republican or Republican‐leaning showed more support for hunting. Also, mutualism wildlife value orientation was negatively related to hunting approval, whereas domination value orientation was positively linked. Understanding public perspectives on these issues can enable the social context of wildlife management to be considered in decision‐making, thereby improving large carnivore management outcomes.

Effects of hunting on mating, relatedness, and genetic diversity in a puma population

J. A. Erwin, et al. 2023. Molecular Ecology DOI: 10.1111/mec.17237

Abstract – Hunting mortality can affect population abundance, demography, patterns of dispersal and philopatry, breeding, and genetic diversity. We investigated the effects of hunting on the reproduction and genetic diversity in a puma population in western Colorado, USA. We genotyped over 11,000 single nucleotide polymorphisms (SNPs), using double-digest, restriction site-associated DNA sequencing (ddRADseq) in 291 tissue samples collected as part of a study on the effects of hunting on puma population abundance and demography in Colorado from 2004 to 2014. The study was designed with a reference period (years 1–5), during which hunting was suspended, followed by a treatment period (years 6–10), in which hunting was reinstated. Our objectives were to examine the effects of hunting on: (1) paternity and male reproductive success; (2) the relatedness between pumas within the population, and (3) genetic diversity. We found that hunting reduced the average age of male breeders. The number of unique fathers siring litters increased each year without hunting and decreased each year during the hunting period. Mated pairs were generally unrelated during both time periods, and females were more closely related than males. Hunting was also associated with increased relatedness among males and decreased relatedness among females in the population. Finally, genetic diversity increased during the period without hunting and decreased each year when hunting was present. This study demonstrates the utility of merging demographic data with large-scale genomic datasets in order to better understand the consequences of management actions. Specifically, we believe that this study highlights the need for long-term experimental research in which hunting mortality is manipulated, including at least one non-harvested control population, as part of a broader adaptive, zone management scheme.

Ravines as conservation strongholds for small wildcats under pressure from free-ranging dogs and cats in Mediterranean landscapes of Chile.

Beltrami, E. et al. 2023. Studies on Neotropical Fauna and Environment 58_138-154

Abstract – The Chilean Mediterranean ecosystem is threatened by anthropogenic pressures, such as habitat loss by intensive agriculture and urban sprawl. Abandoned dogs (Canis lupus familiaris) and cats (Felis silvestris catus) pose conservation challenges for Chilean wildlife including the pampas cat (Leopardus colocolo) and the güiña (Leopardus guigna). We used camera trap data to investigate influences of natural and anthropogenic landscape features on spatiotemporal trends of these species. We also used co-occurrence modeling and kernel density estimation to investigate spatial and temporal patterns overlap of wildcats, free-ranging (FR) dogs, and FR-cats. FR-dogs showed the highest detection and site use probabilities, while güiñas had the lowest across 80 camera trap sites. Top models showed no spatial avoidance between species and co-occurrence of wildcats was positively influenced by forest habitat. However, FR-dogs negatively affected detection of wildcats. Ravines surrounded by forest positively influenced güiña and pampas cat detection probabilities when dominant species were not present. FR-dogs and wildcats had significantly different temporal activity patterns and low overlap coefficients, while wildcats and FR-cats showed high overlap in activity patterns. We suggest changing current policies to control domestic animals and strategic planning in agricultural areas of central Chile to better conserve native wildcat species.

Simulated effects of roadkill and harvest on the viability of a recovering bobcat population

Dyck, M.A. et al. 2023. Journal of Wildlife Management  87:e22460

Abstract – Bobcats (Lynx rufus) were extirpated from many midwestern states in the mid-1800s owing to habitat loss and overharvesting. Recently, bobcats have recolonized Ohio, USA, and neighboring states and given their furbearer status elsewhere, there is interest in opening a harvest season; however, demographic factors and viability of this population are currently unknown. We developed a spatial population simulation model to assess the long-term viability of the bobcat population in Ohio in the face of 2 human-induced factors limiting population growth: potential harvest and road mortality. We combined habitat suitability and road mortality risk data with vital rates for bobcats from Ohio and other populations to simulate possible scenarios for Ohio's population. Our baseline scenario simulations showed no risk of extinction for Ohio's bobcat population in the next 40 years, but population trajectories were lower and exhibited greater uncertainty when we modeled the population with a lower maximum density of animals per cell. At low harvest intensity (αh = 0.05), the bobcat population also exhibits low risk of extinction. When harvest intensity increases (αh = 0.1, 0.15) or when adults (≥2 yr) are targeted by harvest, simulations show declining populations, greater uncertainty in projections, and possible risk of extirpation. Our models indicated that if harvest and road mortality are additive, then the bobcat population could withstand marginal increases in road mortality (αr = 0.1) at low harvest intensity (αh = 0.05). Future increases in road mortality with higher harvest intensity (αh = 0.1, 0.15) were unsustainable. Our results can be used by wildlife managers to assist with decisions on population-level management. This simulation model can easily be adapted for other large mammals and can be modified to assess a variety of ecological and anthropogenic influences to wildlife populations.

Rain, recreation and risk: Human activity and ecological disturbance create seasonal risk landscapes for
the prey of an ambush predator

H.N. Abernathy et al. 2023. Journal of Animal Ecology 92:1840-1855

Abstract –

1. Predation risk and prey responses exhibit fluctuations in space and time. Seasonal ecological disturbances can alter landscape structure and permeability to influence predator activity and efficacy, creating predictable patterns of risk for prey (seasonal risk landscapes). This may create corresponding seasonal shifts in antipredator behaviour, mediated by species ecology and trade-offs between risk and resources. Yet, how human recreation interacts with seasonal risk landscapes and antipredator behaviour remains understudied.
2. In South Florida, we investigated the impact of a seasonal ecological disturbance, specifically flooding, which is inversely related to human activity, on interactions between Florida panthers (Puma concolor coryi) and white-tailed deer (Odocoileus virginianus). We hypothesized that human activity and ecological disturbances would interact with panther-deer ecology, resulting in the emergence of two distinct seasonal landscapes of predation risk and the corresponding antipredator responses.
3. We conducted camera trap surveys across southwestern Florida to collect detection data on humans, panthers and deer. We analysed the influence of human site use and flooding on deer and panther detection probability, co-occurrence and diel activity during the flooded and dry seasons.
4. Flooding led to decreased panther detections and increased deer detections, resulting in reduced deer-panther co-occurrence during the flooded season. Panthers exhibited increased nocturnality and reduced diel activity overlap with deer in areas with higher human activity. Supporting our hypothesis, panthers' avoidance of human recreation and flooding created distinct risk schedules for deer, driving their antipredator behaviour. Deer utilized flooded areas to spatially offset predation risk during the flooded season while increasing diurnal activity in response to human recreation during the dry season.
5. We highlight the importance of understanding how competing risks and ecological disturbances influence predator and prey behaviour, leading to the generation of seasonal risk landscapes and antipredator responses. We emphasize the role of cyclical ecological disturbances in shaping dynamic predator–prey interactions. Furthermore, we highlight how human recreation may function as a ‘temporal human shield,’ altering seasonal risk landscapes and antipredator responses to reduce encounter rates between predators and prey.