CONSERVATION, ECOLOGY, AND EVOLUTION OF MIGRATORY BEHAVIOR IN THE PAINTED BUNTING (Passerina ciris)

In 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

Temporal Migration Patterns Between Natal Locations of Ruby-Throated Hummingbirds (\u3ci\u3eArchilochus colubris\u3c/i\u3e) and Their Gulf Coast Stopover Site

Background Autumn latitudinal migrations generally exhibit one of two different temporal migration patterns: type 1 where southern populations migrate south before northern populations, or type 2 where northern populations overtake southern populations en route. The ruby-throated hummingbird (Archilochus colubris) is a species with an expansive breeding range, which allows opportunities to examine variation in the timing of migration. Our objective was to determine a relationship between natal origin of ruby-throated hummingbirds and arrival at a Gulf coast stopover site; and if so, what factors, such as differences in body size across the range as well as the cost of migration, might drive such a pattern. To carry out our objectives, we captured hummingbirds at a coastal stopover site during autumn migration, at which time we collected feathers from juveniles for analysis of hydrogen stable isotopes. Using the hydrogen stable isotope gradient of precipitation across North America and published hydrogen isotope values of feathers from populations of breeding ruby-throated hummingbirds, we assigned migrants to probable natal latitudes. Results Our results confirm that individuals from across the range (30–50° N) stopover along the Gulf of Mexico and there is a positive relationship between arrival day and latitude, suggesting a type 1 migration pattern. We also found no relationship between fuel load (proxy for migration cost) or fat-free body mass (proxy for body size) and natal latitude. Conclusions Our results, coupled with previous work on the spatial migration patterns of hummingbirds, show a type 1 chain migration pattern. While the mechanisms we tested do not seem to influence the evolution of migratory patterns, other factors such as resource availability may play a prominent role in the evolution of this migration system

Filling the gap: molting behavior of colima warblers and research opportunities for understudied north american songbirds

We implemented stable isotope analysis to evaluate the molt behavior of the Colima warbler (Leiothlypis crissalis), an understudied migratory songbird occurring in Mexico and recently discovered breeding in the southern part of Texas, USA. We built a geostatistical model showing variation in deuterium precipitation values (d2Hp) across a latitudinal gradient within the Colima warbler breeding range in northeastern Mexico. Then, based on stable isotope ratios of deuterium in feathers (d2Hf), we assigned wintering Colima warblers captured in Central Mexico to possible molting areas near the southwestern portion of the species\u27 breeding range. To the best of our knowledge, this is the first field study documenting Colima warbler captures and recaptures within the Parque Ecológico de la Ciudad de México, near the mountain ranges surrounding the Basin of Mexico. Overall, our study demonstrates the potential of winter ecology fieldwork in conjunction with molecular study techniques, such as stable isotope analysis, for revealing the migratory and molting behavior of warblers with restricted distribution ranges

Varying dataset resolution alters predictive accuracy of spatially explicit ensemble models for avian species distribution

Species 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

A tail of plumage colouration: disentangling geographic, seasonal and dietary effects on plumage colour in a migratory songbird

Plumage ornamentation in birds serves critical inter- and intra-sexual signaling functions. While carotenoid-based plumage colouration is often viewed as a classic condition-dependent sexually selected trait, plumage colouration can be influenced by a wide array of both intrinsic and extrinsic factors. Understanding the mechanisms underlying variation in colouration is especially important for species where the signaling function of ornamental traits is complex or when the literature is conflicting. Here, we examined variation in the yellow/orange tail feathers of American redstarts Setophaga ruticilla passing through two migratory stopover sites in eastern North America during both spring and fall migration to assess the role of geographic variation and seasonality in influencing feather colouration. In addition, we investigated whether diet during moult (inferred via stable isotope analysis of feather δ15N and δ13C) influenced plumage colouration. Our findings indicate that geographic variation, season and diet all influence individual differences in American redstart colouration, represented by both traditional and tetrahedral colour variables. The extent to which these factors influence colour expression however is largely dependent on the colour metric under study, likely because different colour metrics reflect different attributes of the feather (e.g. structural components versus pigment deposition). The effects of diet (δ15N) and season were pronounced for brightness, suggesting a strong effect of diet and feather wear/degradation on feather structure. Though hue, a metric that should strongly reflect pigment deposition, also changed from spring to fall, that effect was dependent on age, with only adults experiencing a reduction in ornamentation. Taken together, our results highlight the numerous sources of variation behind plumage coloration and underscores the difficulty of unraveling complex visual signaling systems, such as those in American redstarts

Examination of Clock and Adcyap1 gene variation in a neotropical migratory passerine

Complex behavioral traits, such as those making up a migratory phenotype, are regulated by multiple environmental factors and multiple genes. We investigated possible relationships between microsatellite variation at two candidate genes implicated in the control of migratory behavior, Clock and Adcyap1, and several aspects of migratory life-history and evolutionary divergence in the Painted Bunting (Passerina ciris), a species that shows wide variation in migratory and molting strategies across a disjunct distribution. We focused on Clock and Adcyap1 microsatellite variation across three Painted Bunting populations in Oklahoma, Louisiana, and North Carolina, and for the Oklahoma breeding population we used published migration tracking data on adult males to explore phenotypic variation in individual migratory behavior. We found no correlation between microsatellite allele size within either Clock and Adcyap1 relative to the initiation or duration of fall migration in adult males breeding in Oklahoma. We also show the lack of significant correlations with aspects of the migratory phenotype for the Louisiana population. Our research highlights the limitations of studying microsatellite allelic mutations that are of undetermined functional influence relative to complex behavioral phenotypes.This research was funded by the National Science Foundation (grants nos. IDBR 1014891 and DEB 0946685) and by the United States Department of Agriculture (grant no. NIFA-AFRI-003536). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.YesEach submission to PLOS ONE passes through a rigorous quality control and peer-review evaluation process before receiving a decision. The initial in-house quality control check deals with issues such as competing interests; ethical requirements for studies involving human participants or animals; financial disclosures; full compliance with PLOS’ data availability policy, etc. Submissions may be returned to authors for queries, and will not be seen by our Editorial Board or peer reviewers until they pass this quality control check. Once each manuscript has passed quality control, it is assigned to a member of the Editorial Board, who takes responsibility as the Academic Editor for the submission. The Academic Editor is responsible for conducting the peer-review process and for making a decision to accept, invite revision of, or reject the article

Domesticating the Exotic? An Online Survey of Attitudes towards the International Wildlife Pet Trade

There 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

Habitat loss exacerbates pathogen spread : An Agent-based model of avian influenza infection in migratory waterfowl

Habitat availability determines the distribution of migratory waterfowl along their flyway, which further influences the transmission and spatial spread of avian influenza viruses (ATVs). The extensive habitat loss in the East Asian-Australasian Flyway (EAAF) may have potentially altered the virus spread and transmission, but those consequences are rarely studied. We constructed 6 fall migration networks that differed in their level of habitat loss, wherein an increase in habitat loss resulted in smaller networks with fewer sites and links. We integrated an agent-based model and a susceptible-infected-recovered model to simulate waterfowl migration and AIV transmission. We found that extensive habitat loss in the EAAF can 1) relocate the outbreaks northwards, responding to the distribution changes of wintering waterfowl geese, 2) increase the outbreak risk in remaining sites due to larger goose congregations, and 3) facilitate AIV transmission in the migratory population. In addition, our modeling output was in line with the predictions from the concept of "migratory escape", i.e., the migration allows the geese to "escape" from the location where infection risk is high, affecting the pattern of infection prevalence in the waterfowl population. Our modeling shed light on the potential consequences of habitat loss in spreading and transmitting AIV at the flyway scale and suggested the driving mechanisms behind these effects, indicating the importance of conservation in changing spatial and temporal patterns of AIV outbreaks.Peer reviewe