Browsing by Author "Pejchar, Liba, committee member"
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Item Open Access An evidence-based approach to evaluating the outcomes of conservation education(Colorado State University. Libraries, 2015) Thomas, Rebecca E. W., author; Teel, Tara, advisor; Bruyere, Brett, advisor; Gavin, Michael, committee member; Pejchar, Liba, committee memberThis dissertation responds to a need for theoretically-driven and applied approaches to conservation education that address modern-day conservation challenges. The two primary objectives of this dissertation are addressed in the form of two individual articles. First, Article 1 utilizes a systematic review approach to investigate evaluation of conservation education on a global scale in order to better understand 1) the temporal and spatial trends in conservation education program evaluations over the last 25 years (e.g., whether the frequency of program evaluations has changed both within and outside of the United States); 2) patterns that are evident in the types of conservation and/or social issues addressed through these programs; 3) metrics considered to indicate effectiveness of conservation education programs; and 4) which outcomes of these programs are evaluated (e.g., to what extent do evaluations focus on cognitive targets as well as behavioral, social or ecological outcomes) as well as the methods that have been used to draw conclusions about these outcomes. Findings indicated that evaluation of conservation education programs has increased over the last 25 years in countries around the world. Increasingly, conservation education programs are being developed in response to ecological and social issues, yet metrics to indicate effectiveness are rooted in cognition and behavior change. Three primary needs in the field of conservation education program evaluation emerged from this study and can inform the future direction of the field. First, there is a need to think more holistically about the outcomes of conservation education programs. Secondly, there is a need to consider the ways in which these outcomes are evaluated and reported. Finally, there is a need for longitudinal evaluation, particularly when attempting to capture ecological outcomes that may not be immediately apparent. Article 2 utilizes an applied, person-centered interview approach to address a need for more rigorous and culturally relevant evaluation of conservation education program outcomes that is focused on benefits beyond rote knowledge gain and considers community perspectives on metrics or indicators of program success in a rural community in Hawai'i. The study upon which this article is based sought to compare past and present learning about nature in terms of knowledge acquisition and the knowledge itself. Secondly, the study aimed to set the stage for the development of a culturally relevant and comprehensive quantitative evaluation instrument that could be used to document long-term outcomes of conservation education programs that seek to facilitate sharing of local environmental knowledge in Hawai'i.Item Open Access Breeding waterfowl productivity in a flood-irrigated agricultural landscape(Colorado State University. Libraries, 2023) Setash, Casey M., author; Koons, David N., advisor; Pejchar, Liba, committee member; Gammonley, James H., committee member; Sueltenfuss, Jeremy P., committee memberSimilar to agricultural production, the sustainable management of waterfowl populations across the western United States inherently depends on limited water availability. Both endeavors are increasingly challenged by municipal demands for water, drought, and changes in the seasonality of precipitation. Healthy wetlands for wildlife can be sustained in conjunction with the needs of agricultural producers on working lands, but the multifaceted importance of water management is rarely quantified. Information pertaining to the multiple benefits of water management practices might bring to light the larger societal importance of sound water management. This may allow natural resource managers to allocate resources more efficiently and effectively by directing them towards the practices with demonstrated advantages for both wildlife and agricultural producers. The North Platte Basin in north-central Colorado (hereafter North Park) is a model system to evaluate benefits and trade-offs of hydrological manipulations that benefit both agricultural producers and fish and wildlife. Not only are waterfowl and water management already being conducted by federal and state agencies and NGOs like Ducks Unlimited, but North Park is also representative of many working lands throughout the Intermountain West. Agricultural producers in North Park flood irrigate rather than using center-pivot irrigation, which strongly affects on hydrological regimes, water tables, wetlands, and stream flows. Flood irrigation more closely resembles natural stream and river flood regimes and is thought to be more beneficial for wildlife, water table recharge, and evaporative cooling of return flow water. As water resources become diverted for urban municipal uses and the increasing frequency of drought reduces water availability in the semi-arid West, it is believed that the North Platte Basin may begin to play a significant role in the production of waterfowl on a statewide or even a flyway scale. As private land becomes an increasingly important component of waterfowl habitat and water resources become limiting, a strong foundational knowledge regarding how flood-irrigated systems impact wetland-dependent species will therefore be imperative to properly manage waterfowl populations in coordination with agricultural production. We first sought to evaluate the efficacy of flood-irrigated agricultural lands as nesting habitat for breeding waterfowl in the context of land-use intensity. The debate over the best agricultural practices for biological conservation typically focuses on land sharing and land sparing production strategies. One end of the spectrum posits that high-intensity agriculture and the smaller footprint associated with it allows for other land parcels to be spared for biodiversity and therefore provides more suitable habitat, whereas others argue that agricultural lands should be cultivated at a low intensity and interspersed with wildlife habitat, therefore sharing the land with wildlife. We evaluated the demographic consequences of land-sharing and land-sparing practices on breeding bird nest site selection and nest survival, focusing specifically on waterfowl in a flood-irrigated hay agricultural system. We specifically assessed the habitat features related to both shared and spared lands driving nest site selection at two scales and how those same features scaled up to impact nest survival. Nests were located disproportionately closer to uncut irrigated meadows and farther from harvested hay meadows relative to available points, but closer to irrigation ditches. Nests closer to irrigation ditches, uncut irrigated meadows, and open water also experienced higher nest survival. This system is representative of many agricultural systems around the globe and illustrates the ways agricultural practices can shape habitat selection have reproductive consequences for wildlife. After evaluating the importance of wetlands associated with flood irrigation for nesting, we focused our efforts on elucidating their contributions as foraging habitat. Food availability varies considerably over space and time in wetland systems, and consumers must be able to track those changes during energetically-expensive events like breeding. Resource tracking has been studied frequently among herbivores, but rarely receives attention among consumers of macroinvertebrates. We evaluated the change in resource energy density across habitat types and time, and the ability of waterfowl to track macroinvertebrate resources across wetland types and over the course of the breeding season in a high-elevation, flood-irrigated system. We also assessed whether the density of energy resulting from macroinvertebrates explained more of the variation in waterfowl abundance across habitats, or whether the consistency (i.e., temporal evenness) of the resource played a larger role using a pseudo-R2 metric. Energy density varied widely across wetland types, but was highest in basin wetlands (i.e., ponds) and was higher in wetlands with higher temperatures, specific conductivity, and lower dissolved oxygen. Both breeding pair abundance and duckling abundance were positively associated with energy density and resource consistency (R2 = 0.06 for pair abundance and 0.31 for duckling abundance), but energy density explained more of the variation in both waterfowl responses (R2 = 0.77 for pair abundance and 0.58 for duckling abundance). These results have the potential to not only elucidate mechanisms of habitat selection among waterfowl, but also indicate where and when water resources should be allocated as climate conditions become increasingly arid. The technological tools we used initially to evaluate waterfowl use of flood-irrigated habitats (i.e., Global Positioning System [GPS] tags) have become a common tool in ecological studies of animal behavior and demography despite previous research indicating negative impacts on vital rates across a variety of taxa. We therefore focused next on evaluating the impacts of GPS tags on our focal waterfowl species and others across the life-history spectrum. Researchers face tradeoffs when deciding whether they are an appropriate tool because GPS tags may impact vital rates, but they provide detailed data on movements and behavior that often cannot be obtained in other ways. Using band recovery data from hunter harvests, we evaluated the strength of effects induced by GPS tags on annual mortality of adult females across 13 waterfowl species, and whether species with a slower life-history strategy might be more resilient to GPS tag effects than their fast-lived counterparts. Hazard ratios, indicating the risk of death for individuals wearing GPS tags compared to those wearing only metal bands, ranged from 0.92 - 4.38 and the mean difference in survival between marker types across species was 0.31, but these results are averaged across the study period. The magnitude of tag effects remained constant across life-history tempo, indicating that slower-lived species were not able to buffer the effect of wearing GPS tags. When scaling effect sizes up to a currency of fitness, slower-lived species exhibited a similar handicap of wearing GPS tags compared to species with a faster life-history strategy, and the effects were notable. Our results highlight that even small impacts to important vital rates can affect inference pertaining to survival and mortality as well as fitness from birds affixed with GPS tags. The results of this study revealed considerable survival effects across species, although time trends illustrated decreasing effect sizes for most species over time. Results emphasize the importance of testing for such effects in future research as technology advances. Finally, we used components of each previous chapter to characterize the population of breeding ducks in this system and the demographic consequences of environmental conditions. Waterfowl populations in the Intermountain West rely upon water availability and are not as frequently studied as populations within North American core breeding areas like the Prairie Pothole Region. Different species experience different environmental conditions during peak nest initiation depending on their breeding phenology, especially in variable environments like those associated with high-elevation systems. We fit species-specific integrated population models to evaluate the demographic drivers of mallard and gadwall populations breeding in a high-elevation intermountain basin in Colorado representative of many Intermountain West habitats from 2018-2022. Each species initiated nests at opposite ends of the phenological spectrum, allowing us to assess the effects of environmental conditions on demography. Both mallard and gadwall annual after-hatch-year (AHY) female survival probabilities were comparable to estimates from other regions (hatch-year [HY] mallards = 0.48 [SD = 0.09] to 0.53 [SD = 0.07], AHY mallards = 0.53 [SD = 0.07] to 0.57 [SD = 0.05], HY gadwall = 0.44 [SD = 0.13] to 0.52 [SD = 0.14], AHY gadwall = 0.56 [SD = 0.11] to 0. 66 [SD = 0.12]). Annual recruitment, a metric of the number of females produced per breeding pair, was similar among gadwall (0.62 [SD = 0.80] to 1.04 [SD = 1.04]) and mallards (0.40 [SD = 0.48] to 1.59 [SD = 0.95]), but realized population growth rate (λ) did not vary as much for gadwall (0.93 [SD = 0.56] to 1.21 [SD = 0.59]) as it did for mallards (0.76 [SD = 0.24] to 1.55 [SD = 0.24]). Recruitment of both species exhibited quadratic relationships with spring growing degree days, indicating recruitment was higher during springs with intermediate temperatures, and spring snow-water equivalent metrics in the surrounding mountains positively impacted HY and AHY mallard survival in addition to HY gadwall survival. The results of this study emphasize the need for continued monitoring of waterfowl outside of traditional survey areas and provide insight into water management strategies to target important vital rates as climate and land use change.Item Open Access Demographic consequences of agricultural practices on a long-lived avian predator(Colorado State University. Libraries, 2022) Vennum, Christopher Ryan, author; Koons, David N., advisor; Pejchar, Liba, committee member; Kendall, Bill, committee member; Boone, Randall, committee memberTo view the abstract, please see the full text of the document.Item Open Access Effects of birdwatchers on sandhill crane (Grus canadensis) behavior at spring stopover sites in the San Luis Valley, Colorado(Colorado State University. Libraries, 2012) Wilkins, Kate, author; Moore, John, advisor; Bowser, Gillian, advisor; Angeloni, Lisa, committee member; Pejchar, Liba, committee memberHuman recreational activities can disturb wildlife by causing animals to alter feeding patterns, or change feeding locations. Migratory birds in particular can be susceptible to disturbance since they have limited time for resting, feeding and courtship along their migratory routes. Sandhill cranes (Grus canadensis) are an iconic and charismatic species that stop in Colorado's San Luis Valley during each spring and fall migration, which has led to an annual spring bird watching festival at the Monte Vista National Wildlife Refuge. The goal of this research was to understand how birdwatchers drawn by the festival affect the behavior of sandhill cranes in this important migration stopover site. For the purposes of this research, "birdwatchers" are defined as any person present in the pullouts where we conducted observations of crane behavior. The behavior of sandhill cranes was observed using focal animal sampling techniques during March 2010 and 2011 at sites both on and off the Monte Vista National Wildlife Refuge. The number of birdwatchers at a particular site did not affect the time cranes spent in vigilance postures; however, cranes spent more time vigilant on the Monte Vista National Wildlife Refuge than on privately owned lands, where there were fewer observers. Overall, the results of this study suggest that the birdwatchers during the festival had minimal impact on sandhill crane behavior on the refuge, including open lands managed as agricultural fields. The results of this research can inform adaptive management approaches to balance bird watching opportunities and the needs of charismatic migratory species.Item Open Access Gap analysis of India's Western Ghats protected area network: insights from new and understudied endemic species' distributions(Colorado State University. Libraries, 2018) Miltenberger, Oliver, author; Leisz, Stephen, advisor; Evangelista, Paul, committee member; Pejchar, Liba, committee memberProtected areas are a crucial tool to meet conservation goals of the 21st century, especially in biodiverse regions threatened by land use change. This study makes use of nine years of field data collected on over 300 understudied plants and amphibians endemic to the UNESCO-recognized biodiversity hotspot of the Western Ghats of India to produce a gap analysis of its protected area network. The gap analysis updates previous analyses to reassess network coverage and to improve biodiversity distribution estimates. Software for Assisted Habitat Modeling (SAHM) queries possible species distribution models (SDMs) and predictor variables for thirty-five of these species sub-grouped by range strategies. This generates parsimonious sets of predictor variables as well as performance assessments of SDMs, which then populate batch-run distribution Maximum Entropy models (Maxent). These distributions are overlain in various ensembles to produce clade and biodiversity specific insights about high and low-occurrences areas for these species. Hotspot assessments of the region are generated using ensembled distributions and are compared to the current protected area network to identify gaps in coverage for high-occurrences of these species' distributions. Most high species co-occurrences for both amphibian and plant distributions are covered by the network with the exception of three regions for amphibians and six regions for plants, two of which overlap between clades. Previous studies largely or exclusively used secondary-data for their assessments while the majority of species in this study have never been modeled or included in gap analyses. This study's assessment adds new ecological information to individual species and novel contributions to conservation planning in a threatened biodiversity hotspot. This study recommends inclusion of the seven identified high-occurrences areas in future conservation efforts for the Western Ghats and prioritization of the two areas identified as gaps in protection for both clades.Item Open Access Gunnison sage-grouse demography and conservation(Colorado State University. Libraries, 2012) Davis, Amy Jane, author; Doherty, Paul F., advisor; Phillips, Michael L., committee member; Kendall, William, committee member; Pejchar, Liba, committee member; Webb, Colleen, committee memberTo view the abstract, please see the full text of the document.Item Open Access Interactions between Bromus tectorum, grasshoppers, and native plants in sagebrush steppe communities(Colorado State University. Libraries, 2014) Cumberland, Catherine, author; Paschke, Mark, advisor; Cooper, David, committee member; Jonas, Jayne, committee member; Pejchar, Liba, committee memberInvasion by the exotic grass Bromus tectorum L. (cheatgrass) has produced widespread, persistent changes in the Intermountain West. As a result of this and other disturbances, sagebrush shrubland is among North America's most imperiled ecosystems. Restoration of B. tectorum-infested areas has often been unsuccessful, and there is a need to understand the factors limiting revegetation success. There is evidence that B. tectorum is a superior competitor for space and resources. But it's also possible that B. tectorum dominance is enhanced by native herbivores through the mechanism of apparent competition: species competing indirectly through shared natural enemies. If an invasive exotic is a less preferred food source for herbivores than native plants, per capita feeding impacts may increase on natives, thus facilitating exotic proliferation. In sagebrush shrubland, grasshoppers are often the dominant herbivores. Their feeding patterns have been shown to limit and structure plant distributions. The objective of this study was to elucidate whether grasshoppers may be promoting B. tectorum spread through herbivore-mediated apparent competition. Using native plants commonly seeded in sagebrush restoration projects and the native generalist grasshopper Melanoplus bivittatus in laboratory trials and greenhouse experiments, I tested how grasshopper herbivory affects native plants in comparison to B. tectorum. Grasshoppers significantly increased mortality rates for most native plants but had minimal impact on B. tectorum mortality. Certain native species were much more highly preferred and / or impacted by herbivory, including the keystone shrub Artemisia tridentata (big sagebrush). However, several native species were either less preferred or more tolerant of herbivory than B. tectorum, and could therefore be good restoration candidates where grasshoppers are common. In addition, my results suggest B. tectorum could promote population increase in certain grasshopper species, particularly agricultural and rangeland pests. Study results could provide guidance regarding seed mixes and possible control of insect herbivores to improve restoration success in B. tectorum-invaded areas.Item Open Access Post-fire vegetation and bird habitat use in piñon-juniper woodlands(Colorado State University. Libraries, 2022) Woolet, Jamie, author; Stevens-Rumann, Camille, advisor; Coop, Jonathan, committee member; Pejchar, Liba, committee memberGlobal climate change has caused fire activity and behavior to shift from historical norms due to hotter and drier conditions. Although the ecological effects of changing fire regimes have been explored in many systems, the resilience of some forest types, such as piñon-juniper, are often overlooked. Piñon-juniper is a dominant forest type in the western US and provides breeding habitat for many obligate or semi-obligate bird species. Similarly, this system is supported by a critical mutualism, where the regeneration and infilling of these trees is reliant on several bird species that disperse piñon pine and juniper seeds. This study aimed to assess woodland resilience by evaluating post-fire forest structure and the associated avian communities one-year and 20+ years post-fire. More specifically, seedling regeneration and the habitat use of piñon-juniper obligate bird species, semi-obligates, piñon seed dispersers, and juniper seed dispersers were compared across burned, refugia, and unburned patches. Replicate patches of each habitat type were selected within three fire locations, and 3-4 bird point count stations and 1 forest inventory plot were established in each patch. No tree regeneration was observed 1-year post-fire, and after 25 years, there were few juniper seedlings and no piñon seedlings observed in burned plots. Seedling regeneration and forest structure in refugia and unburned plots were not different, regardless of fire age. Results from occupancy models indicated that Woodhouse's Scrub-jay, a piñon seed disperser, used all habitats equally. American Robin had the highest habitat use in the recent burned patches. Obligate and semi-obligate bird species had differing responses to habitat types, with the habitat use of Ash-throated Flycatcher and Spotted Towhee not differing across habitat types, Virginia's Warbler having the highest habitat use in old burn and refugia patches, the Gray Vireo, Black-throated Gray Warbler, and Gray Flycatcher having highest habitat use in unburned, refugia, and recent burn patches, and the Blue-grey Gnatcatcher having the highest habitat use in the old burn. While there is a need for longer term studies, our work highlights that even 25 years post-fire, little tree recovery is observed and the associated bird species continue to differ, emphasizing the potential transition or long recovery time in these sensitive areas.Item Unknown Songbird trend estimation and density-habitat relationships to inform and prioritize conifer management in the sagebrush and pinyon-juniper ecotone(Colorado State University. Libraries, 2022) Van Lanen, Nicholas J., author; Aldridge, Cameron L., advisor; Pejchar, Liba, committee member; Koons, David N., committee member; Bailey, Larissa L., committee memberTo view the abstract, please see the full text of the document.Item Unknown The economic consequences of private lands conservation using conservation easements in Colorado(Colorado State University. Libraries, 2019) Swartzentruber, Ryan, author; Seidl, Andrew, advisor; Jablonski, Becca B. R., committee member; Pejchar, Liba, committee memberConservation easements have been used across the United States to preserve natural amenities and compensate landowners for the public goods they provide. From the Farm and Ranch Land Protection Program to the Grassland Reserve Program, Colorado conserves 2.4 million acres of land (Colorado Natural Heritage Program and the Geospatial Centroid, 2018) This thesis explores the economic implications of Federal conservation easements through the Agricultural Conservation Easement Program in Colorado. Using Input-Output modeling I found that conservation easements contributed $176 million to Colorado's economic activity. Further Multi-Region Input-Output models showed that conservation easements support rural counties between $106 million and $112 million more than two counterfactuals I considered: decreasing federal income tax and a zero counterfactual. Further, using benefit transfer analysis, I estimated that all conservation easements in Colorado provide between $40 and $47 billion in ecosystem service benefits to Coloradoans. Using econometric meta-analysis techniques, I estimated that Coloradoans are willing to pay $4.3 billion for all the conserved lands in Colorado. I propose an alternative payment methodology which incentivizes landowners to enroll environmentally important lands rather than using development opportunity costs to determine payments.Item Open Access The physiological condition of orphaned African elephants (Loxodonta africana)(Colorado State University. Libraries, 2021) Parker, Jenna Marie, author; Wittemyer, George, advisor; Crooks, Kevin, committee member; Hobbs, Tom, committee member; Pejchar, Liba, committee memberTo view the abstract, please see the full text of the document.Item Unknown The roles of phenotypic plasticity and adaptation in morphology and performance of an invasive species in a novel habitat(Colorado State University. Libraries, 2020) Jardeleza, Marcel Kate Guarin, author; Hufbauer, Ruth A., advisor; Pearse, Ian S., committee member; Pejchar, Liba, committee member; Ghalambor, Cameron K., committee memberInvasive species spread and thrive across widely variable habitats. Their success in novel environments may be influenced by phenotypic plasticity, which occurs when a genotype can produce multiple phenotypes in response to different environments, or local adaptation, the production of traits that are advantageous under the local environmental conditions regardless of their effects in other habitats. One indication of these non-mutually exclusive processes comes in the form of geographic or elevational clines in phenotypes and genotypes. Drosophilla suzukii is an outstanding example of an invasive species that has established across many diverse environments and exhibits an elevational cline in wing size. In my thesis, with collaborators Jonathan Koch, Ian Pearse, Cameron Ghalambor, and Ruth Hufbauer, I evaluated the degree to which plasticity and genetic differentiation determine differences in wing sizes, and whether plasticity appears to be adaptive or not. I first characterized an elevational cline in wing size in D. suzukii on Hawaii and also evaluated its relative abundance by elevation. I then conducted a reciprocal temperature experiment to understand the mechanisms driving the cline. We found that wing size increased with elevation and that D. suzukii was significantly more abundant in higher elevation sites compared to lower elevation sites. Temperature may be the key driver of wing size variation, with wing size increasing as temperature decreased along the elevational gradient. In the reciprocal temperature experiment, I found that temperature had a strong effect on development time and cooler temperatures took longer to emerge compared to warmer temperatures. The reciprocal temperature experiment further revealed strong phenotypic plasticity. When flies from high and low elevation were reared at a cool temperature comparable to that found at high elevation, they produced larger wings. When reared at a warm temperature comparable to that found at low elevation, they produced smaller wings, which is the same pattern of variation observed in field populations. Additionally, I found significant differences in the number of flies that emerged from the two experimental temperatures. Flies from low and high elevation sites produced similar numbers of offspring at the cool temperature, while high elevation flies produced significantly more offspring at the warm temperature compared to the low elevation flies, despite that temperature being their home temperature. My study revealed strong plasticity in wing size, but no indication of local adaptation. If the wing phenotypes observed in high and low elevation populations in the field represent fit phenotypes, then this plasticity is adaptive. The flies may be exhibiting an "all-purpose genotype" where a fit phenotype is produced across the environmental conditions and there is no selection for adaptation to occur. As evidence continues to mount in support of the highly plastic responses of D. suzukii to temperature, particularly with respect to wing size, and the possible adaptiveness of this response, future studies need to make the direct connection between wing plasticity and adaptation. How an invasive organism responds to different environments determines the extent of its novel range and the places that it will impact. Hawaiian populations of D. suzukii exhibit substantial phenotypic variation in wing size, development time, and offspring production with some genetic component to that plasticity.