Ixodes affinis Neumann (Acari: Ixodidae) is a hard-bodied tick species distributed throughout much of the southeastern United States. Although I. affinis does not parasitize humans, it is a competent vector of Borrelia burgdorferi sensu stricto, the causative-agent of Lyme disease, and thus contributes to the enzootic maintenance of this pathogen. This study presents evidence of I. affinis parasitizing five new host passerine species. During 2012-2014, 1,888 birds were captured and examined for ticks, and 18 immature I. affinis were collected from 12 birds-six Carolina Wrens (Thyrothorus ludovicianus); two Brown Thrashers (Toxostoma rufum); and one American Robin (Turdus migratorius), Eastern Towhee (Pipilo erythrophthalmus), Northern Cardinal (Cardinalis cardinalis), and White-throated Sparrow (Zonotrichia albicollis). Of 15 larvae and 3 nymphs collected, one nymph tested positive for B. burgdorferi DNA. I. affinis was found co-feeding on birds with immature Amblyomma americanum (L.), Ixodes brunneus Koch, Ixodes dentatus Marx, Ixodes scapularis Say, and Haemaphysalis leporispalustris Packard. The results of this research provide a better understanding of I. affinis hosts and identify avian taxa that may play a role in the maintenance and dispersal of this tick species.

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ABSTRACT. Flycatchers in the genus Empidonax are among the most difficult avian taxonomic groups to identify to species. Observers often rely on calls or songs in the field or detailed morphometrics in the hand to identify species. In January and February 2013, we twice captured an Empidonax flycatcher at the Virginia Zoo in Norfolk, Virginia. After being unable to identify the flycatcher to species level using morphometrics and photographs, we extracted DNA from two tail feathers collected during the second encounter to identify the individual genetically.Comparison of cytochrome c oxidase I (COI) with reference sequences in the Barcode of Life Database (BOLD) suggested that the specimen had a >99.8% probability of placement as a Dusky Flycatcher (Empidonax oberholseri). Additional comparisons of NADH dehydrogenase subunit 2 (ND2) to reference sequences in GenBank, however, suggested that the specimen was a Pine Flycatcher (Empidonax affinis), a species not represented in BOLD and confined geographically to a small area in Mexico and Guatemala. After analyzing both COI and ND2 from additional vouchered specimens, the bird caught in Virginia was determined to be a Dusky Flycatcher. We also suspect that some of the sequences in GenBank might derive from incorrectly identified specimens or otherwise could represent overlooked pseudogenes. Because the putative identification, based on GenBank sequences, would have represented the first record of Pine Flycatcher from the United States, our results reinforce the need for carefully vetted and taxonomically comprehensive molecular databases to allow definitive conclusions about sample identity. Further molecular phylogeographic review of this genus is warranted to resolve haplotype ambiguities.RESUMEN. Retos sobre la identificación morfológica y molecular de papamoscas del genero Empidonax: un caso de estudio con Empidonax oberholseri Los papamoscas Empidonax se encuentran entre el grupo de aves más difíciles de identificar taxonómicamente a nivel de especies. Para identificar estos pájaros, los observadores dependen, particularmente, del canto o de las llamadas o de detalles que se pueden observar cuando tienen el ave en la mano En enero y febrero del 2013, en dos ocasiones capturamos un Empidonax en el Zoológico de Virginia, Virginia. No pudimos identificar la especie utilizando fotografías o rasgos morfométricos y a tales efectos extrajimos ADN de dos de las plumas del rabo, para tratar de identificar el segundo individuo genéticamente. La comparación de la oxidasa c citocromica I (COI), con la referencia secuencial en la base de datos del "Código de Barras de la Vida" (BOLD) sugirió que el espécimen tenía >99.8% de probabilidad de ser un Empidonax oberholseri. No obstante, una comparación de NADH dehidrogenasa, subunidad 2 (ND2) del Banco Genético (GenBank) sugería que el ave era Empidonax affinis, una especie que no estaba representada en BOLD y geográficamente confinada a unárea pequeña de México y Guatemala. Luego de analizar el COI y el ND2 de especímenes adicio...

One of North America's major avian migratory pathways occurs along a large anthropogenically modified coastal region of southeastern Virginia, USA. Because hundreds of avian species migrate along the east coast of North America, understanding factors affecting birds and their health is of ecological and conservation interest. Within southeastern Virginia, 14 tick species have been documented, all of which may serve as vectors of vertebrate pathogens. We tested 5 hypotheses to understand how varying levels of urbanization within an urban matrix of a coastal region affected avian parasitism rates. We sampled resident and migratory birds for ticks across an urbanization gradient at 5 permanent and 6 ad hoc sites from August 2012 to August 2014 and determined parasitism rates at the landscape and site scales. At the landscape scale, the proportion of birds parasitized by ticks was reduced at more urbanized sites. Urbanized sites were largely associated with higher water and impervious surfaces in the surrounding area, which may have prevented dispersal of ticks or hosts to isolated urban locations, and lower tree cover, which likely reduced tick survival because of decreased leaf litter. At the site scale, properties associated with being on or near the ground (i.e., foraging guild and age) were the best predictors of tick parasitism. These findings demonstrate that the effects of urbanization are neither uniform nor straightforward. In addition to affecting avian species composition, anthropogenic changes to the landscape are affecting the relationship between avian hosts and their parasites, a finding that has important implications for avian conservation efforts and management practices.