64 research outputs found
Grassland bird surveys 2013-2014
No full textProjects derived from point counts, transects, and behavioral surveys conducted by Bridge, Ross, and Contina in 2013-2014 in Oklahoma grasslands
Grassland bird surveys 2013-2014
No full textProjects derived from point counts, transects, and behavioral surveys conducted by Bridge, Ross, and Contina in 2013-2014 in Oklahoma grasslands
Optimizing stable isotope sampling design in terrestrial movement ecology research
No full textThe recognition of adequate sampling designs is an interdisciplinary topic that has gained popularity over the last decades. In ecology, many research questions involve sampling across extensive and complex environmental gradients. This is the case for stable isotope analyses, which are widely used to characterize large-scale movement patterns and dietary preferences of organisms across taxa. Because natural-abundance stable isotope variation in the environment is incorporated into inert animal tissues, such as feathers or hair, it is possible to draw inferences about the type of food and water resources that individuals consumed and the locations where tissues were synthesized. However, modern stable isotope research can benefit from the implementation of robust statistical analyses and well-designed sampling approaches to improve geographic assignment interpretation. We employed hydrogen stable isotope simulations to study inferences regarding the probability of origin of migratory individuals and reveal gaps in sampling efforts while highlighting uncertainties of assignment model extrapolations. We present an integrative approach that explores multiple sampling strategies across species with different geographic ranges to understand advantages and limitations of animal movement inferences based on stable isotope data. We show the characteristics of different sampling strategies through geographic and isotopic gradients and establish a set of diagnostic tools that uncover the attributes of these gradients and evaluate uncertainties of model results. Our analysis demonstrates that sampling regimes should be evaluated in relation to specific research questions and study constraints, and that adopting a single method across species ranges can lead to a costly but less effective sampling strategy
CONSERVATION, ECOLOGY, AND EVOLUTION OF MIGRATORY BEHAVIOR IN THE PAINTED BUNTING (Passerina ciris)
No full textIn animal migration studies, determining the migratory connectivity of different species is a crucial step to understand the ecology and evolution of complex behavioral traits as well as to implement effective conservation management plans of declining species. Intrinsic markers, such as stable isotopes and genetic markers, in conjunction with miniaturized light-level geolocator devices, provide high resolution tools to study the ecology and evolution of migration in birds smaller than 20 grams and offer insight on the breeding population of origin of those individuals trapped and sold in the international pet trade market. For example, from 2005 to 2009, CITES documented more than 317,000 live birds sold annually within an industry estimated to be worth billions of US dollars per year. In this context, migratory species can be particularly difficult to protect because any management effort would necessarily involve cooperation among different countries with distinct laws and regulations. A case in point is the Painted Bunting (Passerina ciris), which breeds primarily in the United States and winters in Mexico, Central America, southern Florida, and the Caribbean. I provide a new library of polymorphic microsatellite loci and offer a new tool for genetic population structure studies, forensic analyses, and conservation management of the Painted Bunting and other related species of the genus Passerina. My results suggest that buntings harvested in Central America for the retail market belong to the western breeding population as opposed to the smaller Atlantic breeding population. However, a percentage of both populations come into contact at the wintering grounds in the Yucatan Peninsula where conservation efforts might need to be strengthened.Furthermore, during my investigations on the molting ecology of the Painted Buntings, I found that birds breeding in Oklahoma and molting in Sinaloa, Mexico, show a clear bimodal pattern of stable isotope ratios in their flight feathers, as previously demonstrated in this species, suggesting that some birds may initiate molt immediately upon arrival in northwestern Mexico whereas others may delay molt. I used geologger tags to test whether differences in the timing and route of fall migration movements were related to stable isotope signatures in primary feathers. I observed variation among individuals in migration routes, wherein birds from the same breeding population differed greatly in their use of molting and wintering locations. However, I did not find a relationship between isotope signatures and the timing or route of fall migration.Furthermore, I investigated possible relationships between variation in two candidate genes implicated in the control of migratory behavior (CLOCK and ADCYAP1) and several aspects of fall migration including initiation date, arrival at molt/stopover sites, and duration of the first leg of fall migration. I evaluated the mutation rate of these candidate genes through an Approximate Bayesian Computation (ABC) coalescent approach and studied the effect of natural selection on their allele frequencies across populations. I found that millennial scale summer temperatures and longitude likely affected the current genotypes of CLOCK and ADCYAP1 in three sampling populations. To search for novel genes associated with migratory performance, I implemented 454 next generation sequencing and generated over 48,000 DNA sequences distributed over the Painted Bunting genome. I assembled an extensive library of candidate genes by annotations extracted from the Mouse Genome Informatics database and I focused on the following candidate genes: ADRA1d, ANKRD17, CISH, and MYH7. I tested these genes across avian migratory and non-migratory species, revealing a surprising degree of allelic variation in some genes. MYH7 correlated with speed of migration (km/day) and body mass across 11 species of songbirds in addition to two novel uncharacterized polymorphic genes that strongly correlated with duration of migration in the Painted Buntings
Calibration chain transformation improves the comparability of organic hydrogen and oxygen stable isotope data
No full textStable hydrogen and oxygen isotopic compositions (δ2H and δ18O, respectively) of animal tissues have been used to infer geographical origin or mobility based on the premise that the isotopic composition of tissue is systematically related to that of local water sources. Isotopic data for known-origin samples are required to quantify these tissue–environment relationships. Although many of such data have been published and could be reused by researchers, differences in the standards used for calibration and analytical procedures for different datasets limit the comparability of these data. We develop an algorithm that uses results from comparative analysis of secondary standards to transform data among reference scales and estimate the uncertainty inherent in these transformations. We apply the algorithm to a compilation of known-origin keratin data published over the past ~20 years. We show that transformation improves the comparability of data from different laboratories, and that the transformed data suggest ecophysiologically meaningful differences in keratin–water relationships among different animal groups and taxa. The compiled data and algorithms are freely available in the ASSIGNR r-package to support geographical provenance research, and more generally offer a methodology overcoming several challenges in geochemical data integration and reuse
Varying dataset resolution alters predictive accuracy of spatially explicit ensemble models for avian species distribution
No full textSpecies distribution models can be made more accurate by use of new “Spatiotemporal Exploratory Models” (STEMs), a type of spatially explicit ensemble model (SEEM) developed at the continental scale that averages regional models pixel by pixel. Although SEEMs can generate more accurate predictions of species distributions, they are computationally expensive. We compared the accuracies of each model for 11 grassland bird species and examined whether they improve accuracy at a statewide scale for fine and coarse predictor resolutions. We used a combination of survey data and citizen science data for 11 grassland bird species in Oklahoma to test a spatially explicit ensemble model at a smaller scale for its effects on accuracy of current models. We found that only four species performed best with either a statewide model or SEEM; the most accurate model for the remaining seven species varied with data resolution and performance measure.
Policy implications: Determination of nonheterogeneity may depend on the spatial resolution of the examined dataset. Managers should be cautious if any regional differences are expected when developing policy from range‐wide results that show a single model or timeframe. We recommend use of standard species distribution models or other types of nonspatially explicit ensemble models for local species prediction models. Further study is necessary to understand at what point SEEMs become necessary with varying dataset resolutions.Article processing charges funded by University of Oklahoma Libraries. This work was funded by U.S. Department of Agriculture (USDA) NIFA grant 2013‐67009‐20369 to ESB and supported by the AWS Cloud Credits for Research program. CMC was supported by National Science Foundation (NSF) grants IDBR 1014891 and ABI 1458402 to ESB and Oklahoma Department of Wildlife Conservation grant F17AF01294 (W‐194‐R‐1) to M.A. Patten. AJC was supported by NSF grants IDBR 1014891, DGE 1545261, and DEB 0946685 and by USDA grant NIFA‐AFRI‐003536. Additional support was provided by the University Strategic Organization in "Applied Aeroecology" at the University of Oklahoma.Ye
Domesticating the Exotic? An Online Survey of Attitudes towards the International Wildlife Pet Trade
No full textThere are a variety of perspectives on wildlife management and conservation, necessitating interdisciplinary research to develop better management strategies. We answered the call to action provided by Teel et al. (2018) to integrate social sciences into conservation and explored an important but understudied issue: views on the international pet-trade of exotic animals. Some pet owners advocate the pet trade as a means to promote conservation, where removing wild animals from their natural habitat could protect them from degraded environments. To gauge how prevalent this attitude is in a cross-national sample, we conducted an online survey that asked 882 participants worldwide to evaluate the pet trade and its relationship with biological conservation. Overall, our survey results showed regional patterns and indicated that younger respondents were more likely to consider international pet trade as a form of acceptable conservation practice compared to older respondents. Education also played a role in shaping views on the pet-trade and indicated that respondents with higher education degrees were less prone to accept pet trade as a substitute for conservation practices. Our research provides novel insights applicable to education programmes and international conservation efforts while highlighting variation in attitudes even among professionals with formal training in natural sciences and ecology
abmR: An R package for agent‐based model analysis of large‐scale movements across taxa
No full textAbstract Agent‐based modelling (ABM) shows promise for animal movement studies. However, a robust, open‐source and spatially explicit ABM coding platform is currently lacking. We present abmR, an R package for conducting continental‐scale ABM simulations across animal taxa. The package features two movement functions, each of which relies on the Ornstein–Uhlenbeck (OU) process. The theoretical background for abmR is discussed and the main functionalities are illustrated using example populations. Potential future additions to this open‐source package may include the ability to specify multiple environmental variables or to model interactions between agents. Additionally, updates may offer opportunities for disease ecology and integration with other R movement modelling packages
Simulation Study Results of abmR: An R Package For Agent-Based Model Analysis of Large-Scale Movements Across Taxa
No full textThis repository contains simulation study results for the example application presented in abmR: an R package for agent-based model analysis of large-scale movements across taxa (Gochanour et al. 2022; in press)
Exploring novel candidate genes from the Mouse Genome Informatics database: Potential implications for avian migration research
No full textTo search for genes associated with migratory phenotypes in songbirds, we selected candidate genes through annotations from the Mouse Genome Informatics database and assembled an extensive candidate-gene library. Then, we implemented a next-generation sequencing approach to obtain DNA sequences from the Painted Bunting genome. We focused on those sequences that were conserved across avian species and that aligned with candidate genes in our mouse library. We genotyped short sequence repeats from the following candidate genes: ADRA1d, ANKRD17, CISH and MYH7. We studied the possible correlations between allelic variations occurring in these novel candidate migration genes and avian migratory phenotypes available from the published literature. We found that allele variation at MYH7 correlated with a calculated index of speed of migration (km/day) across 11 species of songbirds. We highlight the potential of the Mouse Genome Informatics database in providing new candidate genes that might play a crucial role in regulating migration in birds and possibly in other taxa. Our research effort shows the benefits and limitations of working with extensive genomic datasets and offers a snapshot of the challenges related to cross-species validation in behavioral and molecular ecology studies
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