Browsing by Author "Kanno, Yoichiro, committee member"
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Item Open Access Assessing the swimming and jumping performance of Wyoming fishes with implications for fishway design(Colorado State University. Libraries, 2024) Garvey, Chase, author; Myrick, Christopher A., advisor; Kanno, Yoichiro, committee member; Wohl, Ellen, committee memberTo successfully begin to solve the complex problems facing native fish conservation efforts, we need to seek a deeper understanding of the fish that inhabit the communities that we hope to conserve. With regards to the issue facing the fragmentation of our lotic ecosystems, and the effects that dams and similar structures can have on fish communities, fishways are a common tool used to restore the connectivity of streams by allowing the uninhibited passage of fish. In these experiments we studied the swimming and jumping abilities of Hornyhead Chub (Nocomis biguttatus), Bigmouth Shiner (Notropis dorsalis), Iowa Darter (Etheostoma exile), and Brook Stickleback (Culaea inconstans) in order to provide fisheries managers with criteria for fishway design that will allow the passage of desirable target species, and potentially block the spread of invasive Brook Stickleback. We did this by testing the jumping abilities of each species at various temperatures using artificial waterfalls. After testing groups of fish at various waterfall heights, we used logistic regression to predict the probability of individual fish passage under various conditions. To test the swimming ability of each species, we used swim tunnels to determine the maximum swimming velocity of each species, and estimate their endurance at various swimming velocities. Our results show that a vertical barrier greater than 15 cm will block the upstream movement of nearly all individual Hornyhead Chub. Heights greater than 8.4 cm will block the upstream passage of Bigmouth Shiner, and barriers taller than 6.0 cm will block the upstream passage of Iowa Darter and Brook Stickleback. Given this information, if vertical drops and pool designs were to be incorporated into fishways designed for these species, drops between fishway pools should remain within these thresholds if successful passage is to be achieved. The results of the swimming performance experiments show that each species' swimming abilities are unique relative to their raw maximum swimming abilities and overall endurance. The problem facing engineers and biologists is that many different species that make up these communities are unique, and have characteristics that pose specific challenges or advantages to assisting their movements. Additionally, fisheries scientists must remain cognizant that fishways that allow native fish movement will likely allow the movement of non-target species (including potential invasives) present in the same systems. Managers must balance the trade-offs between restoring native ecosystems and protecting areas that have not been invaded.Item Open Access Decreasing stream habitat for Greenback cutthroat trout under future climate projections in headwater streams of the southern Rocky Mountains, Colorado(Colorado State University. Libraries, 2022) Ma, Chenchen, author; Morrison, Ryan R., advisor; Nelson, Peter, committee member; Kanno, Yoichiro, committee memberHeadwaters are vital to the abundance and diversity of biota as they produce various temperatures, light, hydrologic regimes, water chemistry, substrate type, food resources, and species pools. Many studies have shown that headwater streams are especially vulnerable to changing climate, and coldwater fish are especially sensitive to the fluctuations in streamflow and water temperature during summertime low flows. Though previous studies have provided insights on how changes in climate and alterations in stream discharge may affect the habitat requirements for native cutthroat trout species, the suitable physical habitats have not been evaluated under future climate projections for the threatened Greenback Cutthroat Trout (GBCT) occupying the headwater regions in the Southern Rocky Mountains. Thus, this study used field data collected in the summers of 2019 and 2020 from selected headwater streams across the Front Range in the Southern Rocky Mountains to construct one-dimensional hydraulic models (HEC-RAS) to evaluate streamflow and physical habitat under four future climate projections. A principal component analysis (PCA) was then performed to demonstrate the importance of each morphological feature of these streams. Results illustrate high variations in both predicted streamflow reductions and physical habitat for all future climate projections. The projected mean summer streamflow shows much greater decline compared to the projected mean August flow. Moreover, sites located at higher elevations with larger substrate (D50 and D84) and steeper slopes may experience greater reductions in physical habitat under mean summer future climate projections. Future climate change studies on cold-water fisheries need to take multiple influential factors into account instead of heavily focusing on the thermal characteristics. Reintroduction and management efforts for GBCT should be tailored to the individual headwater stream with adequate on-site monitoring that can be applied in a more holistic manner as well.Item Open Access Developing rock ramp fishway criteria for fishes of regional conservation concern(Colorado State University. Libraries, 2024) Paik, Kira, author; Myrick, Christopher A., advisor; Kanno, Yoichiro, committee member; Wohl, Ellen, committee memberRivers and streams in the United States have been greatly fragmented by the construction of instream structures such as dams, diversions, and culverts to meet the growing needs of human populations. Many of these structures inhibit upstream movement by fish species, negatively affecting abundance as well as overall survival. Conservation efforts are looking at restoring connectivity through the installation of fish passage structures or fishways. To improve effectiveness and functionality of these fish passage structures, the swimming abilities of the target species should be considered when creating the design. Rock ramp fishways are becoming increasingly utilized because they can allow passage of a large assortment of species with variable swimming abilities and are highly customizable. Creating cast concrete fishways in this style can also help to reduce the cost of construction of passage structures. We evaluated the passage success of five fish species of conservation concern using an experimental rock ramp fishway at slopes of 2-10%, in 2% increments. This study focused on species of national or regional conservation concern including Topeka Shiner Notropis topeka, Suckermouth Minnow Phenacobius mirabilis, Rio Grande Chub Gila pandora, Rio Grande Sucker Catostomus plebeius, and Mottled Sculpin Cottus bairdii. Our results showed that decreased slope and distances would lead to higher passage success for the five species. For the entire length of the fishway (6.1 m), all species had very high passage probabilities (> 0.9) at the lowest slopes 2 and 4%, and for all species except the Topeka Shiner, the 6% slope also had high passage probabilities (> 0.8). At 8% and 10% slopes, passage success for these species decreased drastically (< 0.31) and would not be recommended for longer fishways (> 2.03 m between resting areas). Based on these results, managers designing fishways for these species should be able to pick ideal combinations of slope and length to successfully allow passage of an acceptable proportion of the fish to attain management goals.Item Open Access Enrichment as a conservation tool to enhance behavior, morphology, gene expression, and survival in Arkansas darters(Colorado State University. Libraries, 2023) Kopack, Christopher J., author; Angeloni, Lisa, advisor; Fetherman, Eric, advisor; Ghalambor, Cameron, committee member; Kanno, Yoichiro, committee memberConservation practitioners often rely on captive breeding programs to supplement wild populations at risk of extinction. While population augmentation has been successful for some taxa, the use of hatchery fish to supplement wild populations can be severely impacted by predation. Elevated predation on hatchery fish may arise because hatchery environments often differ starkly from wild environments, constraining the ability of hatchery fish to phenotypically match the environments in which they are targeted for release. Phenotypic mismatch caused by differences between hatchery and wild environments can limit efforts to conserve fish species at risk of extinction when hatchery-reared fish are used to augment wild populations. Phenotypes adapted to or induced by hatchery environments are thought to be maladapted for life in the wild. Thus, enriching the hatchery environment (abiotically and biotically) to make it more similar to the wild may induce phenotypes, including behavior, morphology, and gene expression profiles, that are better suited to the environments fish will experience after release. Chapter One explores how hatchery-reared fish respond to novel predators and whether those responses can be enhanced to improve survival. Identifying the presence of innate predator recognition and the capacity for learning to recognize predators can inform conservation management practices. We assessed antipredator behavior (time spent moving and distance from a predator) and the efficacy of predator training for three populations of a species of conservation concern, the Arkansas darter (Etheostoma cragini), which is vulnerable to predation by esocid predators like the introduced northern pike (Esox lucius). Arkansas darters demonstrated an innate ability to recognize and respond to a novel esocid predator. Their behavior also changed in response to predator cues (training), though the direction of response to cues was opposite our prediction. Populations differed in their response to the predator treatment, highlighting the potential value of managing populations separately. Our results suggest that antipredator behavior is innate and that exposure to predator cues does affect behavior. This study demonstrates the importance of evaluating enrichment practices and incorporating behavioral observations into conservation programs to guide population-specific management decisions. In Chapter Two, we used a factorial approach to assess whether abiotic enrichment and biotic enrichment (predator recognition training) increase survival of Arkansas darters during encounters with a novel predator. We also assessed the effects of abiotic enrichment on the expression of behavioral and morphological phenotypes across three populations. Morphology and behavior differed among populations and between abiotic treatments, and populations responded differently to the abiotic treatments. Furthermore, we found that in combination with predator training, abiotic enrichment increased the probability of surviving a first encounter with a predator. We therefore recommend conservation practitioners incorporate abiotic enrichment and predator recognition training in the hatchery, as any increase in survival is expected to benefit efforts to conserve this species. In Chapter Three, we took a molecular approach (TagSeq) to elucidate how abiotic enrichment and biotic enrichment impacts the whole-brain gene expression of Arkansas darters, comparing the effects in two hatchery populations to a wild reference population. Although, we found no effect of biotic enrichment on gene expression, we did find that abiotic enrichment has the potential to reduce phenotypic mismatch between hatchery and wild fish, indicating that enrichment may aid current conservation efforts. Overall, these studies suggest a potential role for enrichment in the conservation of imperiled fish, and they highlight the value of a phenotypic approach to managing populations.Item Open Access Genetic background and experience affect courtship behavior in male Trinidadian guppies (Poecilia reticulata)(Colorado State University. Libraries, 2023) Phipps, Nathan M., author; Hoke, Kim, advisor; Angeloni, Lisa, committee member; Kanno, Yoichiro, committee memberAn animal's behavior may be shaped by its genetics and life experience, but the extent to which each of these factors contributes to determining behavioral phenotypes is an outstanding question in biology. Mating behaviors are of particular interest due to their importance in determining fitness. We sought to investigate the genetic architecture of mating behaviors and their plasticity in response to mating experience. Trinidadian guppies (Poecilia reticulata) occur in streams with either high or low predation rates. This genetic background has shaped the evolution of many behavioral phenotypes, including those involved in male courtship strategy. We observed male guppies from high predation, low predation, and intercross populations in their first encounter with a female, then later repeated the encounter to observe how experience affects mating behaviors. We recorded occurrences of three behaviors – sigmoids, forced copulation attempts, and gonopodial swings – to determine how they are affected by sexual experience and genetic background. We found that the frequencies of sigmoids and gonopodial swings vary depending on genetic background and experience. Our findings support existing literature demonstrating that mating behaviors respond plastically to experience. We also found that intercross guppies matched the gonopodial swing and sigmoid frequency phenotypes of the QH genetic line, suggesting that these behaviors may be controlled by loci that are dominant in the high-predation population.Item Open Access How does rock-ramp fishway surface texture affect the passage success of small-bodied Great Plains fishes?(Colorado State University. Libraries, 2021) Brittain, Cole, author; Myrick, Christopher A., advisor; Kanno, Yoichiro, committee member; Angeloni, Lisa, committee memberThe waterways of the North American Great Plains have experienced extensive fragmentation from instream structures and intermittency caused by excessive dewatering. The modifications to these waterways include numerous barriers that prevent the upstream movement of fish. State and federal resource management agencies have turned to fish passage structures to restore connectivity. However, the passage efficiency of current structures may be limited for native small-bodied fish species by a lack of information on how fish swimming behavior and performance are affected by the key fishway design parameters of slope, length, and texture. Recent research has provided more information on fishway slope and length, and identified texture of the surface between the larger roughness elements as an area needing more investigation. We evaluated the effects of four surface textures (smooth; 1 – 2 mm diameter coarse sand; 6 – 10 mm diameter pea gravel, and; 19 – 31 mm diameter small cobble) on the passage success of three native small-bodied fish species, Arkansas Darter (Etheostoma cragini), Flathead Chub (Platygobio gracilis), and Stonecat (Noturus flavus) using a 6.1-m long experimental rock ramp fishway set at a 6% slope. Our results demonstrated that passage success for the Arkansas Darter increased from 0% on the smooth substrate to 32.2% for the small cobble substrate. A similar pattern was observed for the Stonecats, with an increase in passage success from 31.1% on the smooth substrate to 86.7% on the small cobble substrate. Flathead Chub passage success was independent of substrate treatment and exceeded 90% in all cases. Our study suggests that the use of more highly textured substrates is a viable option for increasing the passage success of small-bodied fishes that otherwise do not perform well on rock ramp fishways.Item Open Access Linking organismal physiology and the landscape to predict vulnerability to climate change(Colorado State University. Libraries, 2023) Cicchino, Amanda Stephanie, author; Funk, W. Chris, advisor; Ghalambor, Cameron, committee member; Kanno, Yoichiro, committee member; Hoke, Kim, committee member; Landguth, Erin, committee memberGlobal temperatures continue to increase at unprecedented rates, both in mean and in variance. Thus, a major challenge for scientists of the 21st century is to predict whether species will persist through these changes. One way to partly assess vulnerability to climate change is to investigate the relationships between the environment and traits that are either particularly sensitive to temperature or may confer resilience against thermal changes. In ectotherms, external temperatures dictate their physiology, thus thermal physiological traits may be key to understanding ectothermic persistence. Although population variation is integral to the evolvability of thermal physiological traits, most studies using these traits to infer vulnerability extrapolate data from one or few populations to represent the species. Furthermore, many studies also use coarse metrics of environmental temperatures which may not fully capture the variation experienced by the organism. Here, using a cold-water frog system, I demonstrate the relationships between thermal physiological traits and local environmental temperatures among populations. In my first chapter, I provide a brief overview of ectothermic physiology, environmental thermal landscapes, and the ecology of the two species of tailed frogs that I investigated. In my second chapter, I show that populations of tailed frogs vary in their critical thermal limit (CTmax) plasticity, which impacts species-level assessments of vulnerability. I also demonstrate the methodological impacts of ignoring acute responses to temperature when estimating plasticity in this trait. For my third chapter, I demonstrate relationships between CTmax and local thermal environments, including temporal and spatial variability in temperature, among populations of tailed frogs. These results show that tailed frogs have limited opportunity for behavioural avoidance of warm temperatures, and that populations of one tailed frog species show a positive relationship between CTmax and maximum stream temperature while populations of the other species does not. In my fourth chapter, I test the critical assumption that CTmax is related to fitness, specifically mortality in ecologically relevant temperatures. My results show that populations with higher estimates of CTmax experience less mortality from thermal stress in temperatures experienced in nature, demonstrating the link between CTmax and fitness. Lastly, in my fifth chapter, I return to the plasticity in CTmax results and demonstrate the relationship between this trait and local thermal environments, showing that populations experiencing greater temperature fluctuations have greater estimates of plasticity in CTmax. Overall, these results underscore the importance of sampling widely among populations when inferring vulnerability to climate changes from physiological traits. The population variation in CTmax and its plasticity that I uncovered demonstrate the differing trends in vulnerability to climate change for the two species investigated. This work also highlights the importance of quantifying local thermalscapes and highlight how similar environments can differentially shape physiological tolerance and patterns of vulnerability among populations, in turn impacting vulnerability to future warming.Item Open Access Rites of passage: determining the efficacy of different fish passage designs along the northern Colorado Front Range(Colorado State University. Libraries, 2022) Jones, Rachel, author; Myrick, Christopher, advisor; Kanno, Yoichiro, committee member; Wohl, Ellen, committee memberAs historical instream barriers continue to be used and new man-made structures have the potential to further fragment river habitat, eastern Colorado fish communities face mounting challenges to survive in abbreviated river segments. Instream barriers are myriad in shape (dams, diversions, culverts, grade control, etc.) and serve a wide variety of economic and social necessities, often preventing their removal. In an attempt to restore longitudinal connectivity at instream barriers, fish passage structures of various types have recently been installed across the northern Colorado Front Range where rivers transition from high gradient mountain streams to low gradient eastern plains streams (often referred to as the transition zone). These structures are often designed with small-bodied native Plains fish species in mind. Frequently, little to no post-installation monitoring is performed for these fishways, so little is known of their comparative success. The goal of this study was to assess the passage success of the resident fish fauna at different passage structures to better understand how structure type and design affect efforts to restore connectivity. The study used long-term monitoring and short-term enclosure studies with stationary PIT tag antenna arrays that recorded movements of a free-ranging community of PIT-tagged fishes. A cast concrete rock ramp on the Cache La Poudre River and a grouted boulder wingwall bypass passage structure on the St. Vrain River were continuously monitored for nearly two years, offering insights into passage success, differences in functionality between the fishways, and the variable movement patterns of the local fish communities. Successful fishway passage was observed at both sites by numerous species over a variety of conditions, with the rock ramp passing 71% of tagged species with an overall passage rate of 55% for individuals, and the wingwall bypass passing 61% of tagged species at an overall individual passage rate of 62%. The long-term monitoring study is described in Chapter 1 of this thesis. Short-term enclosure experiments were used to evaluate both fish passage success at a given passage and to evaluate the method's capability to provide a rapid initial assessment of fishway performance. These trials added an additional pool-and-weir style passage to the two sites used in the long-term monitoring component of the study. Similar to the long-term monitoring study, the rock ramp and wingwall bypass structures both allowed passage of a majority of species, 63% and 70%, respectively, tested during the enclosure study producing overall passage rates of 49% and 64%, respectively. Conversely, fish passage at the pool-and-weir structure was largely non-existent (passage rate of 17%), suggesting it is not a satisfactory alternative for systems where the goal is to provide passage for non-jumping native fish species. The results from this study are described in detail in Chapter 2. Given the differing effects of design features and slopes on passage success for the types tested, this project suggests that future fish passage projects in these systems consider rock ramp-style structures, with specific attention to low gradients and nature-like designs where possible. In addition, long-term monitoring should be considered paramount for post-installation monitoring as it provided the greatest insight into fish passage performance. Many species, not constrained by limited time and conditions, demonstrated higher rates of passage. Greater detail of movement patterns and preferences throughout time was also obtained. However, the short-term enclosure trial process, with some refinements, can provide a valuable initial assessment of fishway functionality following construction.Item Open Access Temporal demography of lesser scaup: a species in decline(Colorado State University. Libraries, 2020) Navarre, Kelsey, author; Koons, David, advisor; Kanno, Yoichiro, committee member; Aldridge, Cameron, committee memberA central goal of wildlife management and conservation is to determine which demographic parameters have the greatest influence on population growth rate to focus management actions for species of concern. Understanding how environmental conditions influence intra- and interannual variation in demographic parameters, and in turn population growth rates, requires long-term studies. This allows researchers to account for temporal covariation in demographic parameters that may have a greater influence on population dynamics than direct variation in the demographic parameter. One such species that could benefit from a better understanding of temporal variation and covariation in demographic parameters is lesser scaup (Aythya affinis, hereafter scaup), which has declined continentally since the early 1980's. I contributed to and utilized a long-term study of scaup demography at Red Rock Lakes National Wildlife Refuge in southwestern Montana, USA to 1) explore how environmental conditions influenced intra- and inter- annual variation in clutch size and nest survival, and 2) incorporate temporal (co)variation in demographic parameters into population models to decouple the influence of parameter variation, versus covariation, on population growth rate. To address my first objective, I considered an array of environmental covariates that were hypothesized to influence inter-annual variation in clutch size and nest survival such as water levels, water level phenology, and water temperature. In addition, I considered intra-annual covariates that could influence these vital rates, such as nest initiation date and day of the breeding season, which could serve as proxies for seasonal changes in resources, predators, or both. Clutch size varied much more within years across nest initiation dates (3.18-10.05), than it did across years (7.51 – 8.38). Given the constrained range of clutch sizes across years, none of the environmental covariates exhibited significant relationships with clutch size. In contrast, nest survival varied little intra-annually (e.g. 2018 nest survival 0.38 ± 0.03), but greatly interannually (0.27 – 0.58). Water level phenology did influence nest survival, such that years when maximum lake levels were reached late in the breeding season relative to mean nest initiation date, had the highest nest survival rates. To address my second objective, I incorporated results from my first chapter along with annual estimates of female breeding propensity, duckling survival, first-winter survival of females, adult female seasonal survival, process variance of each vital rate, and correlation between each pair of vital rates into a time-variant population model and conducted a prospective and retrospective perturbation analysis of population growth rates. The population model revealed that the study population is declining by approximately 6% each year. Results from the prospective perturbation analysis indicated that breeding season and non-breeding season adult survival had the highest stochastic elasticities (0.84 and 0.82 respectively), and thus had the greatest potential to influence the stochastic population growth rate. Whereas, retrospective analyses indicated that fluctuations in duckling survival made the largest contribution to realized population growth rates in the past (64%). Additionally, covariation in demographic rates explained 37% of variation in realized growth rates compared to 63% being attributable to direct temporal variation in the vital rates. These findings collectively suggest efforts to manage water phenology at Red Rock Lakes National Wildlife Refuge could positively influence nest survival and efforts should focus on finding ways to increase duckling survival to have the greatest impact on population growth rate. More broadly, covariation in demographic rates can explain a large proportion of variation in population growth rate and should be incorporated into population models of declining species to more accurately determine points in the life cycle that truly drive population dynamics, and therefore provide sound information to managers aiming to conserve the species.