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Item Spatial Risk Effects From Lions Compound Impacts of Prey Depletion on African Wild Dogs(Wiley, 2024-10) Goodheart, Ben; Creel, Scott; Schuette, Paul; Droge, Egil; Becker, Justine A.; Banda, Kambwiri; Kusler, Anna; Matsushima, Stephi; Banda, Kachama; Kabwe, Ruth; Donald, Will; Reyes de Merkle, Johnathan; Kaluka, Adrian; Chifunte, Clive; Becker, Matthew S.Prey depletion threatens many carnivore species across the world and can especially threaten low-density subordinate competitors, particularly if subordinates are limited to low densities by their dominant competitors. Understanding the mechanisms that drive responses of carnivore density to prey depletion is not only crucial for conservation but also elucidates the balance between top-down and bottom-up limitations within the large carnivore guild. To avoid predation, competitively subordinate African wild dogs typically avoid their dominant competitors (lions) and the prey rich areas they are associated with, but no prior research has tested whether this pattern persists in ecosystems with anthropogenically-reduced prey density, and reduced lion density as a result. We used spatial data from wild dogs and lions in the prey-depleted Greater Kafue Ecosystem to test if wild dogs continue to avoid lions (despite their low density), and consequently avoid habitats with higher densities of their dominant prey species. We found that although lion density is 3X lower than comparable ecosystems, wild dogs continue to strongly avoid lions, and consequently avoid habitats associated with their two most important prey species. Although the density of lions in the GKE is low due to prey depletion, their competitive effects on wild dogs remain strong. These effects are likely compounded by prey-base homogenization, as lions in the GKE now rely heavily on the same prey preferred by wild dogs. These results suggest that a reduction in lion density does not necessarily reduce competition, and helps explain why wild dogs decline in parallel with their dominant competitors in ecosystems suffering from anthropogenic prey depletion. Protecting prey populations within the few remaining strongholds for wild dogs is vitally important to avoid substantial population declines. Globally, understanding the impacts of prey depletion on carnivore guild dynamics should be an increasingly important area of focus for conservation.Item A Latitudinal Gradient of Reference Genomes(Wiley, 2024-10) Linck, Ethan B.; Cadena, Carlos DanielGlobal inequality rooted in legacies of colonialism and uneven development can lead to systematic biases in scientific knowledge. In ecology and evolutionary biology, findings, funding and research effort are disproportionately concentrated at high latitudes, while biological diversity is concentrated at low latitudes. This discrepancy may have a particular influence in fields like phylogeography, molecular ecology and conservation genetics, where the rise of genomics has increased the cost and technical expertise required to apply state-of-the-art methods. Here, we ask whether a fundamental biogeographic pattern—the latitudinal gradient of species richness in tetrapods—is reflected in the available reference genomes, an important data resource for various applications of molecular tools for biodiversity research and conservation. We also ask whether sequencing approaches differ between the Global South and Global North, reviewing the last 5 years of conservation genetics research in four leading journals. We find that extant reference genomes are scarce relative to species richness at low latitudes and that reduced representation and whole-genome sequencing are disproportionately applied to taxa in the Global North. We conclude with recommendations to close this gap and improve international collaborations in biodiversity genomics.Item The value of long-term ecological research for evolutionary insights(Springer Science and Business Media LLC, 2024-08) Cocciardi, Jennifer M. et al.; Borokini, Israel T.Scientists must have an integrative understanding of ecology and evolution across spatial and temporal scales to predict how species will respond to global change. Although comprehensively investigating these processes in nature is challenging, the infrastructure and data from long-term ecological research networks can support cross-disciplinary investigations. We propose using these networks to advance our understanding of fundamental evolutionary processes and responses to global change. For ecologists, we outline how long-term ecological experiments can be expanded for evolutionary inquiry, and for evolutionary biologists, we illustrate how observed long-term ecological patterns may motivate new evolutionary questions. We advocate for collaborative, multi-site investigations and discuss barriers to conducting evolutionary work at network sites. Ultimately, these networks offer valuable information and opportunities to improve predictions of species’ responses to global change.Item Multiscale habitat suitability modeling for a threatened raptor offers insight into ecological model transferability(Elsevier BV, 2024-10) Nayeri, Danial; Cushman, Samuel; Ganey, Joseph; Hysen, Logan; Szykman Gunther, Micaela; Willey, David; Yi Wan, HoHabitat fragmentation and loss are major threats to species conservation worldwide. Studying species-habitat relationships is a crucial first step toward understanding species habitat requirements, which is necessary for conservation and management planning. However, some species inhabit a range of habitat types, potentially making the use of range-wide habitat models inappropriate due to non-stationarity in species-habitat preferences. The Mexican spotted owl (Strix occidentalis lucida) (MSO) is a species that inhabits both forests and rocky canyonlands, two habitats with large differences in environmental conditions. It is unclear whether the species uses habitat differently in these two habitat types or if previously-built habitat models for forest-dwelling owls can be used to understand MSO habitat use in rocky canyonlands. To explore this, we developed the first scale-optimized habitat suitability model for this subspecies of spotted owl in rocky canyonlands using an ensemble framework. We then compared our results with a previously-built habitat model for MSO in forested areas. In the rocky canyonland model, slope (800 m scale), cumulative degree days (1200 m scale), insolation (1000 m scale), and monsoon precipitation (100 m scale) were the most important environmental covariates. In contrast, in the forest model, percent canopy cover (100 m scale), percent mixed-conifer (5000 m scale), and slope (500 m scale) were the most important environmental covariates. The rocky canyonland model performed well, while the forest model performed poorly when projected to rocky canyonlands and predicted low suitability across the entire study area, including areas with known nesting locations. These results support the non-stationarity in habitat use for MSOs between rocky canyonland and forest habitats. Hence, when transferring habitat suitability models from one region to another, it is necessary to evaluate the transferability of the model by accounting for non-stationarity in species-habitat preferences.Item Dynamics of a plant–pollinator network: extending the Bianconi–Barabási model(Springer Science and Business Media LLC, 2024-06) Castillo, William J.; Burkle, Laura A.; Dormann, Carsten F.We study the dynamical assembly of weighted bipartite networks to understand the hidden mechanisms of pollination, expanding the Bianconi–Barabási model where nodes have intrinsic properties. Allowing for a non-linear interaction rate, which represents the seasonality of flowers and pollinators, our analysis reveals similarity of this extended Bianconi–Barabási model with field observations. While our current approach may not fully account for the diverse range of interaction accretion slopes observed in the real world, we regard it as an important step towards enriching theoretical models with biological realism.Item Climate change vulnerability of Arctic char across Scandinavia(Wiley, 2024-07) Muhlfeld, Clint C.; Cline, Timothy J.; Finstad, Anders G.; Hessen, Dag O.; Perrin, Sam; Thaulow, Jens; Whited, Diane; Asbjørn Vøllestad, LeifClimate change is anticipated to cause species to shift their ranges upward and poleward, yet space for tracking suitable habitat conditions may be limited for range-restricted species at the highest elevations and latitudes of the globe. Consequently, range-restricted species inhabiting Arctic freshwater ecosystems, where global warming is most pronounced, face the challenge of coping with changing abiotic and biotic conditions or risk extinction. Here, we use an extensive fish community and environmental dataset for 1762 lakes sampled across Scandinavia (mid-1990s) to evaluate the climate vulnerability of Arctic char (Salvelinus alpinus), the world's most cold-adapted and northernly distributed freshwater fish. Machine learning models show that abiotic and biotic factors strongly predict the occurrence of Arctic char across the region with an overall accuracy of 89 percent. Arctic char is less likely to occur in lakes with warm summer temperatures, high dissolved organic carbon levels (i.e., browning), and presence of northern pike (Esox lucius). Importantly, climate warming impacts are moderated by habitat (i.e., lake area) and amplified by the presence of competitors and/or predators (i.e., northern pike). Climate warming projections under the RCP8.5 emission scenario indicate that 81% of extant populations are at high risk of extirpation by 2080. Highly vulnerable populations occur across their range, particularly near the southern range limit and at lower elevations, with potential refugia found in some mountainous and coastal regions. Our findings highlight that range shifts may give way to range contractions for this cold-water specialist, indicating the need for pro-active conservation and mitigation efforts to avoid the loss of Arctic freshwater biodiversity.Item Dynamics of a plant–pollinator network: extending the Bianconi–Barabási model(Springer Science and Business Media LLC, 2024-06) Castillo, William J.; Burkle, Laura A.; Dormann, Carsten F.We study the dynamical assembly of weighted bipartite networks to understand the hidden mechanisms of pollination, expanding the Bianconi–Barabási model where nodes have intrinsic properties. Allowing for a non-linear interaction rate, which represents the seasonality of flowers and pollinators, our analysis reveals similarity of this extended Bianconi–Barabási model with field observations. While our current approach may not fully account for the diverse range of interaction accretion slopes observed in the real world, we regard it as an important step towards enriching theoretical models with biological realism.Item Prioritizing Imperiled Native Aquatic Species for Conservation Propagation(1944-687X, 2023-10) Webb, Molly A.H.; Guy, Christopher S.; Treanor, Hilary B.; Wilson, Krissy W.; Mellon, Cassie D.; Abate, Paul; Crockett, Harry J.; Hofmeier, Jordan; Pasbrig, Chelsey; Isakson, PatrickNative aquatic species are in decline, and hatcheries can play an important role in stemming these losses until larger ecological issues are addressed. However, as more federal and state agencies face budget uncertainty and the number of imperiled species increases, it is necessary to develop a tool to prioritize species for conservation propagation. Our objective was to create prioritized lists of aquatic species that may benefit from conservation propagation for five states in the United States. Biologists developed an influence diagram and provided information for multiple attributes affecting prevalence of species. The influence diagram and information for each species was used in a Bayesian belief network to generate a score to prioritize propagation of a species and the feasibility of propagation. When all taxa were ranked together within a state, mussels, amphibians, and a crustacean were included among fishes in the top species that may benefit from propagation. We recognize that propagation is one tool for conservation of imperiled species and that additional factors will need to be addressed to ensure species persistence. Nevertheless, we contend our quantitative approach provides a useful framework for prioritizing conservation propagation.Item Diverse habitats shape the movement ecology of a top marine predator, the white shark Carcharodon carcharias(Wiley, 2024-04) Jewell, Oliver J. D.; Chappel, Taylor K.; Jorgensen, Salvador J.; Kanive, Paul; Moxely, Jerry H.; Tweedley, James R.; Anderson, Scot; Block, Barbara A.; Gleiss, Adrian C.An animal's movement is influenced by a plethora of internal and external factors, leading to individual- and habitat-specific movement characteristics. This plasticity is thought to allow individuals to exploit diverse environments efficiently. We tested whether the movement characteristics of white sharks Carcharodon carcharias differ across ontogeny and among habitats along the coast of Central California. In doing so, we elucidate how changes in internal state (physiological changes coinciding with body size) and external environments (differing seascapes and/or diel phases) shape the movement of this globally distributed predator. Twenty-one white sharks, from small juveniles to large adults, were equipped with motion-sensitive biologging tags at four contrasting seascapes: two islands, a headland, and an inshore cove. From multisensor biologging data, 20 metrics characterizing movement (i.e., depth use, vertical velocities, activity, turning rates, and bursting events) were derived and subjected to multivariate analyses. Movement characteristics were most different across seascapes, followed by ontogeny and diel phase. Juvenile sharks, which were only encountered at the cove, displayed the most distinct movement characteristics. Sharks at this seascape remained close to the shore traveling over smaller areas, shallower depth ranges, and with lower levels of tail beat frequencies, when corrected for size, than sub-adult and adult sharks tagged elsewhere. Distinct tortuous daytime versus linear nighttime horizontal movements were recorded from sharks at island seascapes but not from those at the headland or inshore cove. At the offshore islands, the linear nighttime swimming patterns coincided with repeated dives to and from deeper water. The availability of prey and access to deeper water are likely drivers of the differences in movement characteristics described, with varying demographics of pinniped prey found at the subadult and adult aggregation areas and juvenile sharks being piscivorous and their habitat neither adjacent to pinniped haul out areas nor deeper water. This study demonstrates plasticity in the movements of a top predator, which adapts its routine to suit the habitat it forages within.Item Exotic Grass Invasion Increases Forage Productivity and Reduces Diversity of a High Altitude Mesic Grassland(Montana State University, 2021-02) Weaver, T; Bao, SMesic temperate rangeland, e.g. from the North American mixed grass prairie, Rocky Mountain grasslands and southern hemisphere continents is being invaded by the exotic rhizomatous grasses, Poa pratensis and Bromus inermis. To project the effects of their invasion on one grassland, we compared community properties in- and outside of clones invading a level environmentally homogeneous meadow representative of our high altitude fescue grasslands. Yields increased from native vegetation dominated by Festuca idahoenis (Feid, x= 96 gm/m2) through exotic vegetation dominated by Poa (x= 158 gm/m2) to Brome (x= 258 gm/m2) with little difference in forage quality (protein content). Some, e.g. a grazier, might therefore view the change as beneficial. Measurement of community composition in the three communities showed a considerable impoverishment of the native fescue (Feid) community by exotic invasion, an impoverishment understated by measured reduction in species richness [i.e. from Feid (16-12 species per 1.13m2) through Poa (11) to Brome (4 ); species evenness (Simpson) [i.e. from 88-84 to 81 to 42 ]; and life-form evenness (%forb) [i.e, Feid (42-34%) through Poa (23%) to Brome (5%). The impoverishment probably resulted first, from competitive exclusion of natives by lack of soil resources captured by exotics (whose entry surely demonstrated a superior capacity to acquire water and nutrients) and second, for natives associated with taller Brome, from a reduction of ground-level light, a deficiency confirmed by etiolation of the natives. Conservationists will surely decry the losses. Due to the inexorable rhizomatous spread of Poa and Brome and the resultant impossibility of controlling them, we deduce that managers should accept the foresee-able [vegetation] type-conversion and develop methods for managing/using the new vegetation- - a resigned reaction paralleling the response necessary for other anthropogenic factors: urbanization, N-supplementation, pollution and climate change. We expect parallel responses in other mesic grasslands. Sampling and statistics completed 2014- 20l5. 1st draft reviewed 2016.