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Causes for genomic and morphological similarities among recently radiated species are often multifaceted and are further convoluted among species that readily interbreed. Here, we couple genomic and morphological trait comparisons to test the extent that ancestry and gene flow explain the retention of mallard-like traits within a sister species, the Mexican duck. First, we confirm that these taxa remain genetically structured, and that Mexican ducks exhibit an isolation-by-distance pattern. Despite the assumption of wide-spread hybridization, we found only a few late-stage hybrids, all from the southwestern USA. Next, assessing 23 morphological traits, we developed a genetically-vetted morphological key that is > 97% accurate in distinguishing across sex-age cohorts of Mexican ducks, mallards, and hybrids. During key development, we determined that 25% of genetically pure, immature male Mexican ducks of the northern population naturally displayed mallard-like traits in their formative plumage. In fact, applying this key to 55 museum specimens, we identified that only four of the 14 specimens originally classified as phenotypic hybrids were truly hybrids. We discuss how genomic and morphological comparisons shed light into the mechanism(s) underlying the evolution of complex phenotypic traits in recent radiations, and how misunderstanding the true morphological diversity within Mexican ducks resulted in taxonomic revisions that hindered conservation efforts.

Species range expansions and contractions can have ecological and genetic consequences, and thus are important areas of study for conservation. Hybridization and introgression are not uncommon in closely related populations that experience secondary contact during a range expansion. Allen’s Hummingbird (Selasphorus sasin) in California comprises two subspecies: the migratory S. s. sasin, which winters in central Mexico and breeds in central and northern California, and the resident S. s. sedentarius, which lives and breeds year-round on several of the Channel Islands off the California coast. Within recent decades, Allen’s Hummingbirds have been found living and breeding year-round in the southern California peri-urban mainland near Los Angeles. Ornithologists assumed that the L.A. birds were an expansion of the island subspecies, S. s. sedentarius due to similar but very subtle morphological characteristics. However, the genetic relationships among the three putative populations of Allen's hummingbird—migratory, southern California mainland, and island—are unknown. We investigated these relationships by analyzing variation of single nucleotide polymorphisms from the three geographic regions where S. sasin are present. Our population genomic analyses indicate that S. sasin hummingbirds inhabiting mainland southern California are a hybrid population resulting from admixture between S. s. sasin and S. s. sedentarius. From one perspective, these results may be interpreted as a positive development for S. s. sasin as the growing population represent an overall increase in the S. sasin population, and the expanding population contains a significant representation of S. s. sasin alleles.

Abstract Causes for genomic and morphological similarities among recently radiated species are often multifaceted and are further convoluted among species that readily interbreed. Here, we couple genomic and morphological trait comparisons to test the extent that ancestry and gene flow explain the retention of mallard-like traits within a sister species, the Mexican duck. First, we confirm that these taxa remain genetically structured, and that Mexican ducks exhibit an isolation-by-distance pattern. Despite the assumption of wide-spread hybridization, we found only a few late-stage hybrids, all from the southwestern USA. Next, assessing 23 morphological traits, we developed a genetically-vetted morphological key that is > 97% accurate in distinguishing across sex-age cohorts of Mexican ducks, mallards, and hybrids. During key development, we determined that 25% of genetically pure, immature male Mexican ducks of the northern population naturally displayed mallard-like traits in their formative plumage. In fact, applying this key to 55 museum specimens, we identified that only four of the 14 specimens originally classified as phenotypic hybrids were truly hybrids. We discuss how genomic and morphological comparisons shed light into the mechanism(s) underlying the evolution of complex phenotypic traits in recent radiations, and how misunderstanding the true morphological diversity within Mexican ducks resulted in taxonomic revisions that hindered conservation efforts.

Abstract: This paper reports on a bat survey conducted in November 2011 in Mangolo Nature Park and Rawa Aopa Watumohai National Park, both lowland forests located in Southeast Sulawesi. We recorded 22 species of bats that represents nearly 1/3 of the total bat species known to occur on Sulawesi. Three of these are endemic to Sulawesi and adjacent islands, whereas one species, Myotis cf. ridleyi was identified as a new distributional record for this island and with further investigation could prove to be an undescribed species. Our record of Chironax melanocephalus tumulus provided a range extension to the southeastern arm of Sulawesi. Two specimens of Hipposideros boeadii were topotypes and represent the first collections after the description of the type specimen. Collections of Rhinolophus arcuatus from this survey were only the second record of this species from island and represent a range extension. Specimens of Megaderma spasma celebensis were the first records of this species from Southeast Sulawesi. Species are discussed individually with external, cranial and dental measurements summarized. Based on this survey, the number of bat species now documented from the lowlands of Southeast Sulawesi represents the highest diversity yet recorded from a site on Sulawesi. This region is therefore a high priority for conservation and a hotspot for bat research in Indonesia, especially Sulawesi.

In 2001, roof rats were identified as major predators of open-cup songbird nests in old growth riparian forests of California’s Central Valley. Nest predation was as high as 80%. For some bird species in recent years, the populations had declined, and their range was reduced. A management strategy to reduce rat impacts on songbirds was considered a priority. Following a review of the literature and consultation with land managers and experts in rodent management and bird conservation, we decided to reduce rat populations with poison baits delivered in bait stations immediately prior to the songbird nesting period. We subsequently conducted studies to provide information on rat home range and habitat use, potential baits, optimal bait station placement and distribution, and the potential non-target hazards of the program. The management strategy was then implemented in one riparian forest tract in October - December 2003. This is an adaptive management approach that will be evaluated in 2004, modified as necessary, and if successful, potentially applied to other riparian forests. In this paper we describe our approach to developing the management strategy, provide preliminary results, and discuss some of the potential problems with its implementation on a large scale.

ABSTRACT The Florida mottled duck (Anas fulvigula fulvigula) is threatened by introgression through hybridization with feral mallards (A. platyrhynchos). An essential component in managing this threat is the ability to accurately distinguish mottled ducks from mallards and hybrids in the wild. We provide a genetically cross‐validated phenotype key that accurately identifies mottled ducks. We collected data on structural and plumage traits from museum specimens of Florida, USA, mottled ducks and mallards to identify morphological traits useful in this process. We performed extensive comparisons and discriminant function analysis to identify traits informative in distinguishing the 2 species. We used these traits to preliminarily assign 168 contemporary birds as putative mottled duck, mallard, or hybrid. We collected tissue samples from each contemporary specimen and amplified and genotyped associated DNA. We used microsatellite markers to determine posterior probability species assignments for the 168 specimens. We then performed recursive partitioning of phenotypic traits and posterior genotype assignments to create identification keys based on the most informative traits separating mottled ducks from mallards and hybrids. Finally, we cross‐validated the keys by comparing assignments made using the key to those from genotyping for 339 wild ducks. The keys were >90% accurate, which suggests that their adoption will increase the ability of managers to address the threat of hybridization by mallards by allowing mottled ducks to be distinguished from other ducks in Florida. Our research provides a methodology to develop genetically cross‐validated identification keys for other species threatened by genetic introgression. © 2016 The Wildlife Society.

The primary purpose of this study was to determine the effectiveness of the standing long jump (SLJ) and the single-leg hop (SLH) tests to discriminate lower quadrant (low back and lower extremities) injury occurrence in female collegiate soccer players. The secondary purpose of this study was to determine associations between injury and off-season training habits or anthropometric measures. SLJ, SLH, and anthropometric measures were collected during a preseason screening clinic. Each subject completed a questionnaire providing demographic information and off-season training habits. Each athlete performed three SLJ and three SLH per leg. SLJ and SLH scores were not associated with an increased risk of a noncontact time-loss lower quadrant (LQ) injury. Athletes with a higher BMI or who reported less time training during the off-season were two times more likely to sustain an injury. Athletes who had both a higher body mass index (BMI) and lower off-season training habits were three times (relative risk = 3.1 (95% CI: 1.7, 5.5) p-value = 0.0001) more likely to sustain a noncontact time-loss lower quadrant injury. Preseason SLJ and SLH scores do not discriminate injury risk in female collegiate soccer players. Higher BMI and lower off-season training habits are associated with an increased risk of LQ injury.

Since 1989, we have conducted a large-scale ecological experiment in semiarid thorn scrub of a national park in north-central Chile. Initially, we focused on the role of biotic interactions including predation, interspecific competition, and herbivory in small mammal and plant components of the community. We utilized a reductionist approach with replicated 0.56 ha fenced grids that selectively excluded vertebrate predators and/or larger small mammal herbivores such as the degu, Octodon degus. Although we detected small transitory effects of predator exclusions on degu survival and numbers, other species failed to show responses. Similarly, interspecific competition (i.e., degus with other small mammals) had no detectable numerical effects (although some behavioral responses occurred), and degu-exclusions had relatively small effects on various plant components. Modeling approaches indicate that abiotic factors play a determining role in the dynamics of principal small mammal species such as O. degus and the leaf-eared mouse (Phyllotis darwini). In turn, these are mainly related to aperiodic pulses of higher rainfall (usually during El Niño events) which trigger ephemeral plant growth; a food addition experiment in 1997-2000 verified the importance of precipitation as a determinant of food availability. Since 2004, we have expanded long-term monitoring efforts to other important community components including birds and insects in order to understand effects of abiotic factors on them; we report some of the first results of comprehensive surveys on the former in this region. Finally, we recently shifted focus to documenting effects of exotic lagomorphs in the park. We installed additional treatments selectively excluding small mammals, lagomorphs, or both, from replicated grids in order to evaluate putative herbivore impacts. In conjunction with increased annual rainfall since 2000, we predict that introduced lagomorphs will have increasing impacts in this region, and that more frequent El Niños in conjunction with global climatic change may lead to marked changes in community dynamics. The importance of long-term experimental studies is underscored by the fact that only now after 20 years of work are some patterns becoming evident.Desde 1989 hemos llevado a cabo un experimento ecológico a gran escala en un matorral espinoso semiárido de un parque nacional en el norte de Chile. Inicialmente, nos centramos en el rol de las interacciones bióticas incluyendo depredación, competencia interespecífica y herbivoría en micromamíferos y componentes vegetales de la comunidad. Usamos una aproximación reduccionista con parcelas replicadas cercadas de 0.56 ha que selectivamente excluían depredadores vertebrados y/o micromamíferos herbívoros más grandes como el degu, Octodon degus. Aunque detectamos efectos transitorios menores en la sobrevivencia y número de degus en las exclusiones de depredadores, otras especies no mostraron respuestas. Similarmente, la competencia interespecífica (i.e., degus con otros micromamíferos) no tenía efectos numéricos detectables (aunque ocurrieron algunas respuestas conductuales), y las exclusiones tuvieron efectos relativamente pequeños en varios componentes vegetales. Aproximaciones basadas en modelos indican que los factores abióticos juegan un papel determinante en la dinámica de las especies de micromamíferos principales como O. degus y la laucha orejuda (Phyllotis darwini). En cambio, estos están principalmente relacionados a pulsos no periódicos de lluvias más altas (usualmente durante los eventos El Niño) que gatilla el crecimiento de plantas efímeras; un experimento de adición de alimento en 1997-2000 verificó la importancia de la precipitación como un determinante de la disponibilidad de alimento. Desde el 2004 hemos expandido los esfuerzos de monitoreo de largo plazo a otros componentes comunitarios importantes incluyendo aves e insectos con el fin de entender los efectos de los factores abióticos sobre ellos; informamos algunos de los primeros resultados de censos comprehensivos de aves en esta región. Finalmente, hace poco cambiamos de foco para documentar el efecto de lagomorfos exóticos en el parque. Instalamos tratamientos adicionales excluyendo selectivamente micromamíferos, lagomorfos, o ambos, de parcelas replicadas con el fin de evaluar impactos de herbívoros. En conjunto con el aumento de la precipitación anual desde 2000, predecimos que los lagomorfos introducidos tendrán mayores impactos en esta región y que más frecuentes El Niño en combinación con el cambio climático global puede conducir a cambios marcados en la dinámica comunitaria. La importancia de experimentos de largo plazo es destacado por el hecho que solamente ahora después de 20 años de trabajo algunos patrones están siendo evidentes.

On 6-9 December 1993 and 14-18 February 1994 ground surveys of shorebirds were conducted in Ensenada Pabellones and Bahia Santa Maria, Sinaloa, Mexico. These were the first comprehensive ground surveys of shorebirds conducted in western Mexico. Twenty-nine species of shorebirds were recorded. The composition was characterized by those species spending their non-breeding period on the Pacific Coast of North America. Total numbers of shorebirds estimated were 340,063 birds (December) and 405,483 birds (February) in Ensenada Pabellones and 248,044 birds (December) and 389,841 birds (February) in Bahia Santa Maria. Western Sandpiper (Calidris mauri) comprised 82% of shorebirds present in both bays. American Avocet (Recurvirostra americana; 6% average total), dowitchers (Limnodromus spp.; 6% average total), and Least Sandpiper (Calidris minutilla; 3% average total) were also abundant. These bays hold approximately 30% of the shorebirds wintering in Pacific coastal regions of North America. Using Western Hemisphere Shorebird Reserve Network criteria, both bays are of international importance for shorebirds. Ensenada Pabellones is of regional importance for American Avocets supporting nearly 10% of the total world population. Both bays would qualify as wetlands of international importance as defined by the Ramsar Convention on international wetlands., Many North American breeding birds are Neotropical migrants that move to wintering areas in South and Central America (DeGraaf and Rappole 1995, Hagan and Johnston 1992). The decline of habitats [...]

The movement of banded sub-adult Hawaiian stilts, Himantopus mexicanus knudseni, in the various Hawaiian islands they inhabit was tracked to determine the short-term, predispersal movements in this species. The movement patterns were recorded based on sex, age and season. Results reveal that Hawaiian stilts are capable of extensive, even inter-island movements, throughout the year. Males are more predisposed to move probably because they are looking for breeding opportunities.

The Poo-uli (Melamprosops phaeosoma), a Hawaiian honeycreeper discovered on the island of Maui in 1973 and now near extinction, is represented in museums by only two specimens. Based on the first observations of a nesting pair and re-examination of the two specimens, we describe the adult male and female, eggshells, nestling, and fledgling Poo-uli. Poo-uli are sexually monochromatic but males are brighter. The male is brown above, whitish below, and has an extensive black mask bordered with gray on the crown and a distinct white auricular patch. The female differs in having a similar facial pattern not as sharply demarked and in having a grayish wash below. The observed fledgling resembled the adults but was paler brown above and whitish below and had a much smaller black mask and pale mandible. We tentatively assigned both museum specimens to first basic plumage because they resembled the adult female but retained some pale juvenal coloration in the mandible. We also determined from dissection that the holotype was an immature male; we could not determine sex of the paratype. The nest was an open cup of twigs and bryophytes with a thin lining of fern rootlets. The nest contained eggshell fragments with brown-gray speckling against a whitish background. The nests, eggshells, and nestlings resemble those of other Hawaiian honeycreepers., The Poo-uli (Melamprosops phaeosoma), discovered on the island of Maui in 1973, is the most recent, and presumably last, described extant genus and species of Hawaiian bird (Casey and Jacobi [...]