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The soil burial context of a bird bone assemblage is affected by many different taphonomic factors. In this pilot study, we examined the potential effects of soil shrink-swell on white-tailed dove (Zenaida asiatica) bones experimentally buried in three soils of different clay contents. We predicted that bones buried in high clay soils would experience the most damage from soil shrink-swell. Dove wing and leg bones were buried and exposed to 60 days and eight episodes of cyclic soil shrink-swell. We recovered all bones (humeri, ulnae, radii, femora, and tibiotarsi) and found 77.1% of them to exhibit damage. Significant damage occurred among the humeri, ulnae, radii, and femora buried in high clay soil, supporting our prediction. Each bone experienced at least one of the 10 fracture types we recorded. We found the greatest damage in humeri, for which all experienced damage from pitting. The humeri sample also displayed eight fracture types across bone portions and landmarks. Our pilot study is exploratory and meant to provide information useful for further experimentation with additional bird bones using whole carcasses and excised specimens placed in additional positions and soil conditions.

La incidencia de trastornos en la coloración pigmentaria corporal en aves en México ha sido escasamente documentada. Reportamos un individuo de paloma ala blanca (Zenaida asiatica) con envejecimiento en Ciudad Victoria, Tamaulipas. Discutimos los posibles factores físicos que pueden inducir a esta anormalidad pigmentaria.

Los factores biomecánicos, el comportamiento e historia natural de las especies pueden influenciar la forma y dimensión del ala en las aves. Por lo tanto, la morfología de las alas de cada especie podría estar adaptada al ambiente en el que habitan. En palomas (familia Columbidae) existe un gradiente de especies que tienden a volar mucho y otras que vuelan muy poco. El objetivo de esta investigación es determinar si la forma de las alas de seis especies de palomas se asocia con su capacidad de vuelo. Predecimos que las especies Patagioenas flavirostris y P. nigrirostris que tienden a volar largas distancias presentan alas relativamente largas y puntiagudas; mientras que Geotrygon montana que se desplaza principalmente caminando presenta alas relativamente anchas y redondeadas. Especies con capacidad de vuelo intermedio (Leptotila verreauxi, L. cassini y Zenaida asiatica) van a presentar alas con características intermedias. Estimamos la carga alar, proporción de la forma, conicidad alar, largo relativo y el área alar promedio para cada especie. Realizamos un análisis discriminante para determinar cuál combinación de variables explica mejor la diferencia morfológica de las alas entre las seis especies y probamos que tan robusto es este modelo mediante una prueba binomial. El modelo clasificó correctamente el 57 % de los individuos en su propia especie. Por lo tanto, encontramos que el tipo de desplazamiento predominante en cada una de las seis especies de Columbidae analizadas, se asocia con la morfología alar: alas adaptadas para vuelos en zonas abiertas en P. flavirostris y P. nigrirostris, alas adaptadas para vuelos muy maniobrables en hábitats densos en G. montana, y alas con características intermedias en L. verreauxi, L. cassini y Z. asiatica.

El proceso de urbanización se ha acelerado en el último siglo y se estima que crece en 1.1% cada año, causando que los centros urbanos sean cada vez más comunes. Las áreas verde urbanas son importantes, ya que brindan un lugar donde las especies pueden resguardarse y alimentarse, permitiéndoles adaptarse a los paisajes urbanizados. En la ciudad de San Salvador, un espacio con presencia de árboles y arbustos es el campus de la Universidad de El Salvador. El objetivo de esta investigación fue actualizar el conocimiento de la avifauna que utiliza el área verde como sitio de descanso, alimentación o nidificación. Durante un año (febrero 2017 a enero 2018) realizamos un muestreo mensual, revisamos literatura y colecciones disponibles para elaborar un listado histórico y actualizado de la riqueza de aves del lugar. Registramos 64 especies, de las cuales 14 constituyen nuevos registros para el sitio. Las especies con mayor número de observaciones fueron Brotogeris jugularis, Zenaida asiatica y Quiscalus mexicanus. Con los registros actuales y los datos históricos, la riqueza de aves asciende a 100 especies en la Universidad de El Salvador. Destacamos la presencia de Eupsittula canicularis, Psittacara strenuus y B. jugularis, amenazadas localmente y Amazona auropalliata, en peligro de extinción local e internacional.

RESUMEN . El estudio de la estructura de comunidades de aves esta relacionado con su relevante papel en el ecosistema, y cobra mayor importancia cuando se hallan expuestas al dano colateral por actividades antropogenicas. Esta investigacion tuvo por objetivo determinar la variacion de la estructura en la comunidad de aves en el manglar de El Conchalito, BCS, mediante la aplicacion de indices ecologicos como diversidad (H´), dominancia (D) e indice de valor biologico (IVB), durante abril-julio de 2016 en la temporada de transicion primavera - verano. Para describir el marco ambiental, se realizaron mediciones de temperatura, nivel de ruido y clorofila a . Igualmente, se utilizaron datos climatologicos. Se registraron 15 especies de aves acuaticas, marinas y/o costeras (5 ordenes, 7 familias y 9 generos) y 3 especies de aves terrestres (2 ordenes, 2 familias, 3 generos). Las maximas abundancias de aves se registraron durante los primeros muestreos. La diversidad oscilo entre H´= 1.1 y H´= 1.8, con maximos al inicio y final del periodo de estudio. Esto se relaciona con mareas bajas e incremento en la riqueza de especies, respectivamente. El nivel de ruido y concentracion de clorofila a no se asociaron directamente con los cambios observados en la estructura de la comunidad. La riqueza especifica se asocio de manera directa con el incremento de temperatura. Las especies de aves mas importantes fueron: Egretta thula (96.9%), Zenaida asiatica (88.7%), Numenius phaeopus (86.8%) y Egretta rufescens (83.8); de menor importancia fue Ceryle alcyon (28.2). Se identificaron 3 especies sujetas a proteccion (NOM-059-SEMARNAT-2010). Avifaunal community structure associated to El Conchalito mangrove, BCS, Mexico under different tide conditions ABSTRACT. The importance in the study of avian community structure relates to their relevant role in the ecosystem. Specially, when they are exposed to collateral damage by anthropogenic activities. The goal of this research was to determine the variation of avian community structure in the mangrove forest El Conchalito, BCS through the use of ecological indices such as diversity (H’), dominance (D), and the biological value index (IVB) in April-June of 2016 during the seasonal transition from Spring-Summer. To describe the environmental frame, measurements of temperature, noise level, and chlorophyll a were made, and other climatological data were used. A total of 15 species of aquatic, marine or shore birds were recorded (5 orders, 7 families and 9 genera), and 3 species of terrestrial birds (2 orders, 2 families and 3 genera). Maximum bird abundances were observed during the first sampling. Diversity values varied between H´= 1.1 and H´= 1.8, with maxima at the beginning and at the end of the study period. This was related with the low tides and the increase of species richness, respectively. Noise level and chlorophyll a concentration, were not associated directly with the changes observed in the community structure. Species richness was associated directly with temperature increase. The most important bird species were: Egretta thula (96.9%), Zenaida asiatica (88.7%), Numenius phaeopus (86.8%), and Egretta rufescens (83.8); less important was Ceryle alcyon (28.2). Three species protected under NOM-059-SEMARNAT-2010

Sarcocystis calchasi is a recently described apicomplexan parasite that causes encephalitis in avian hosts. We diagnosed one White-winged Dove ( Zenaida asiatica ) and two Eurasian Collared Doves ( Streptopelia decaocto ) in Texas, US, with a history of neurologic signs with protozoal encephalitis. On histologic examination, all three doves had moderate to severe meningoencephalitis characterized by large numbers of plasma cells, lymphocytes, and macrophages with gliosis and astrocytosis. Brain sections from two doves also contained numerous Mott cells. Protozoal schizonts with rosettes or clusters of individual merozoites consistent with Sarcocystis spp. were seen within areas of inflammation. Sarcocysts were also identified in the skeletal muscle of one dove. The PCR and sequencing of brain and skeletal muscle from two doves revealed 99% identity with S. calchasi. The presence of S. calchasi in fatal cases of encephalitis in doves in Texas suggests that the geographic and host ranges of S. calchasi are broader than previously reported.

Las colisiones de las aves con diversas construcciones humanas (e.g., ventanales de cristal) son el segundo factor de mortalidad más importante en paisajes urbanos después de la depredación por gatos. Se ha estimado que alrededor de 988 millones de aves mueren anualmente solamente en los Estados Unidos y Canadá por estos factores. Entre agosto de 2015 y septiembre de 2016 evaluamos la frecuencia de colisiones aves-ventanas en el Centro Universitario Victoria de la Universidad Autónoma de Tamaulipas en el noreste de México. Para detectar aves muertas por colisiones realizamos recorridos en busca de cadáveres dentro de una franja perimetral (tres metros de ancho) alrededor de cuatro edificios durante dos sesiones diarias de muestreo (09:00-10:00 h y 16:00- 17:00 h). Identificamos 21 aves en el suelo de 16 especies, de éstas el 50% de las especies fueron residentes y del total de colisiones 16 fueron fatales. Las especies con mayor incidencia fueron la paloma ala blanca (Zenaida asiatica) con cuatro individuos y el colibrí pico ancho (Cynanthus latirostris) con tres. Durante el muestreo también detectamos cinco especies de aves residentes con conducta agonística contra su reflejo en las ventanas con vidrio reflejante de los edificios del campus universitario. Proponemos algunas medidas para mitigar el número de colisiones de aves en el CUV (e.g., colocación de bandas de colores en las ventanas). Las especies que colisionaron representaron el 5.2% de las especies descritas para el municipio de Victoria. Determinamos mayor frecuencia de colisión en los edificios con vidrios reflejantes. Es necesario seguir desarrollando más estudios de colisiones de aves usando metodologías sistemáticas, que incluyan puntos de conteo simultáneos para considerar la prevalencia de las especies en el sitio de estudio con el fin de documentar el impacto de la urbanización en las poblaciones y comunidades de aves en diferentes centros y paisajes urbanos de México. La determinación de los factores que más influyen en las tasas de colisión de aves-ventanas ayudará en el desarrollo de acciones efectivas de manejo para reducir las colisiones en diferentes escalas espaciales y temporales.

Con la excepción de unas pocas ciudades grandes, hay poco conocimiento sobre las aves urbanas de América Latina. Utilicé transectos lineales en 15 parques urbanos en la ciudad de San José entre setiembre y diciembre de 2009 y encontré 40 especies, la mayoría Tyrannidae (n=10) y Parulidae (n=9). Hubo 23 residentes (principalmente Tyrannidae), 15 migrantes del norte (en su mayoría Parulidae) y un migrante del sur. Las especies más representativas fueron Contopus sp. y Setophaga petechia. Zenaida asiatica, Turdus grayi y Quiscalus mexicanus estaban muy extendidos, al igual que la paloma Columba livia, que podía llegar a 122 individuos por parque. La diversidad y la abundancia fueron determinadas por el tamaño del parque, la complejidad de la vegetación y la proximidad a los fragmentos de vegetación. Los parques urbanos están siendo utilizados como áreas transitorias y permanentes por las aves migratorias y las características biofísicas de algunos parques favorecen a Columba livia y Quiscalus mexicanus, generando competencia, depredación y desplazamiento de otra especie, así como daños a la infraestructura. Estas áreas verdes podrían usarse para la observación y educación de aves.

The white-winged dove (Zenaida asiatica) serves an important ecological role as a diurnal pollinator of the saguaro cactus in the Sonoran desert and an economic role as a highly sought after game bird in North America. White-winged doves are intimatelylinked to anthropogenic changes on the landscape and because of this, have experienced dramatic population fluctuations over the last 75 years in response, both positively and negatively, to anthropogenic changes on the landscape. To understand the factors driving population growth and decline of migratory species like the white-winged dove, it is imperative we study resource use on both their breeding and wintering grounds. To understand how populations are distributed on the wintering grounds, we tested an alternative to band recovery approaches by using stable isotope analysis. Before we could use isotope analysis to link breeding and wintering locations for this species, we first needed to determine if hydrogen (d 2 H) and carbon (d 13 C) stable isotopes in feather tissue (d 2 Hf and d 13 Cf, respectively) could differentiate among populations of white-winged doves across their breeding range in Texas, New Mexico, and Arizona. d 2 Hf and d 13 Cf not only differentiated between populations of white- winged doves that breed in the United States, but d 2 Hf also provided further differentiation in white-winged doves that breed in native Sonoran Desert and agricultural habitats in the western portion of their range. Ecological processes associated with desert resources and anthropogenic influences, specifically saguaro cacti and irrigated crops, largely determined d 2 Hf in some white-winged doves in Arizona whereas d 2 Ho f precipitation (d 2 Hp) largely determined d 2 Hf of doves in New Mexico and Texas. This study highlights the usefulness of stable isotope analysis to differentiate populations of animals across the landscape and the insight isotopes can provide into habitat and resource use. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

We report the use of stable isotope and crop content analyses to quantify the use of saguaro (Carnegiea gigantea) nectar and fruit by migratory desert white-winged doves (Zenaida asiatica mearsnii). Saguaro resources had characteristically 13C-enriched CAM values (δ13C=–12.8±0.7‰ SD VPDB and –13.1±0.5‰ SD VPDB for nectar and fruit, respectively) relative to other food plants used by doves (δ13CC3=–24.9±3.3‰ SD VPDB). The water contained in saguaro nectar and fruit was deuterium enriched (δD=19.6±2.0‰ SD VSMOW and 48.4±1.6‰ SD VSMOW for nectar and fruit, respectively) relative to other water sources (ranging from –41 to –19‰ VSMOW). During the fruiting season, there was a positive correlation between δ13C in dove liver tissues and percent of saguaro in crop contents. A two-point mixing model indicated that during the peak of saguaro fruit use, most of the carbon incorporated in dove tissues was from saguaro. Desert white-winged doves appear to be saguaro specialists. Averaged over the period when doves were resident, saguaro comprised about 60% of the total carbon incorporated into dove tissues. Tissue δ13C and δD of body water showed a significant positive correlation, indicating that doves were using saguaro as a source of both nutrients and water. However, at the peak of saguaro utilization, the doves’ body-water δD was more positive (by about 20‰) than saguaro fruit water. We hypothesize that this enrichment is due to fractionated evaporative water losses by doves. Using dove carbon isotope data and a two end-point mixing model we estimate that, on average, doves consume the equivalent of 128 saguaro fruits per season; each fruit contains on average 26.0±14.8 g SD of pulp (wet mass) of which 19.4 g is water. Stable isotopes have been used to produce qualitative re-constructions of animal diets. Our study shows that they can be used to provide quantitative estimates of the flow of nutrients from resources into consumers as well.

Band recoveries provide requisite data for evaluating the spatial distribution of harvest relative to the distribution of breeding stocks for a wide variety of migratory species. We used direct and indirect band-recovery data to evaluate the distribution and derivation of harvest of white-winged doves (Zenaida asiatica) banded before hunting season in 3 distinct strata in Texas, USA, during 2007-2010. We banded 60,742 white-winged doves during 2007-2010, and based on 2,458 harvest recoveries, the majority (>95%) of white-winged dove harvest occurred during the first 2 months of the hunting season (Sep-Oct). Juvenile white-winged doves represented a greater percentage of the direct recoveries than adults across all strata (north ¼ 80%, central ¼ 69%, south ¼ 82%) and the majority of direct band recoveries (north ¼ 75%, central ¼ 90%, south ¼ 78%) occurred within the original banding strata. Age-specific weighting factors and harvest derivation indicated that both juvenile and adult harvest were highest within the strata of original banding. Harvest distribution data corrected for band-reporting rates indicated high fidelity of white-winged doves to specific geographic strata, with little interplay between strata. Our results suggest that population vital-rate estimates for survival and harvest for use in future Adaptive Harvest Management should focus on stock-specific levels. 2012 The Wildlife Society.

Management of migratory birds at the national level has historically relied on regulatory boundaries for definition of harvest restrictions and estimation of demographic parameters. Most species of migratory game birds are not expanding their ranges, so migratory corridors are approximately fixed. White- winged doves (Zenaida asiatica), however, have undergone significant variation in population structure with marked range expansion occurring in Texas, and range contraction in Arizona, during the last 30 years. Because >85% of white-winged dove harvest in the United States (approx. 1.3 million annually) now occurs in Texas, information on vital rates of expanding white-winged dove populations is necessary for informed management. We used band recovery and mark-recapture data to investigate variation in survival and harvest across 3 geographic strata for white-winged doves banded in the pre-hunting season in Texas during 2007- 2010. We banded 60,742 white-winged doves, recovered 2,458 bands via harvest reporting, and recaptured 455 known-age birds between 2007 and 2010. The best supporting model found some evidence for geographic differences in survival rates among strata (A-C) in both hatch-year (juvenile; A ¼ 0.205 (SE ¼ 0.0476), B ¼ 0.213 (SE ¼ 0.0278), C ¼ 0.364 (SE ¼ 0.0254)) and after-hatch year (adult; A ¼ 0.483 (SE ¼ 0.0775), B ¼ 0.465 (SE ¼ 0.0366), C ¼ 0.538 (SE ¼ 0.251)) birds. White-winged doves had a low probability of moving among strata (0.009) or being recaptured (0.002) across all strata. Harvest recovery rates were concordant with estimates for other dove species, but were variable across geographic strata. Based on our results, harvest management strategies for white-winged doves in Texas and elsewhere should consider differences in population vital rates among geographic strata. 2012 The Wildlife Society.

The helminth community composition and structure of 6 species of columbids residing in south Texas are reported and compared herein. Sixty individuals of the following species, rock pigeons (Columba livia [RP]), mourning doves (Zenaida macroura [MD]), Eurasian collared-doves (Streptopelia decaocto [ECD]), white-winged doves (Zenaida asiatica [WWD]), and common ground doves (Columbina passerina [CGD]), and 48 Inca doves (Columbina inca [ID]) were collected during the summer of 2006 and examined for helminths. Twelve helminth species were found (9 nematodes and 3 cestodes), representing 486 individuals. Nematodes numerically dominated the component community in all host species. Overall, helminth prevalence was similar among host sex within all dove species. However, prevalence of Skrjabinia bonini and Hymenolepis sp. in RPs was significantly different among host age groups (P = 0.01, P = 0.0002, respectively). Likewise, prevalence of Killigrewia delafondi was higher (P = 0.0001) in adult WWDs. Based on percent similarity and Jaccard's coefficient of community indices, helminth component communities were dissimilar, and the number of shared helminth species varied among host species. Data from this study suggest that the environment surrounding preferred host habitat and foraging strategies of each host species is the driving force behind helminth component communities. This study emphasizes the importance of examining co-occurring hosts at both local and regional scales to elucidate helminth community structure and patterns.

We tested whether presence of white-winged doves (Zenaida asiatica) and mourning doves (Z. macroura) in South Texas, USA, was associated with any of the land cover types recorded in the 2001 National Land Classification Database. We used the point-transect method to conduct presence–absence surveys for both species at 236 points encompassing 744 observations. Within predefined land cover types surrounding each survey point, we used Geographic Information Systems to determine the proportions of each land cover type present. We used randomization tests to compare proportions of land cover types present at points with and without doves. We used Program DISTANCE to estimate dove densities at survey points and to test whether certain land cover types were associated with greater dove densities. Our results indicated white-winged dove occurrence in South Texas was positively associated with urban land and cropland, whereas mourning dove occurrence was positively associated with cropland. For land cover...

Populations of North American grassland birds have suffered drastic declines. The causes of these declines are only partially understood and may vary among regions. During the 2004 and 2005 breeding seasons we recorded survival information from 220 nests of four bird species in nine study sites representing three habitat types of the desert grasslands of central Mexico, where grassland birds had not yet been studied. We predicted that land-use change from shortgrass steppe to heavily grazed savannah-type grasslands and agriculture would negatively affect nesting success, number of fledglings and nest abundance. We also examined temporal effects on reproductive success. We found some evidence that nest survival of savannah sparrows Passerculus sandwichensis, loggerhead shrikes Lanius ludovicianus and white-winged doves Zenaida asiatica varied with date, and that nest survival of the dove was lowest in agricultural sites. However, confidence intervals were large, suggesting that other variables were also important. Whereas white-winged dove nests were notably more abundant in agricultural areas compared to the other habitat types, western meadowlark Sturnella neglecta nests were not found in agricultural areas. Ploughing caused the largest proportion of nest failures in agricultural areas and, on average, all species fledged fewer young per nest in agricultural areas. Therefore, minimizing agriculture and adjusting harvest times could enhance conservation of grassland-nesting birds in central Mexico. Our study also suggests that inter-annual variation in rainfall can change the onset of nesting by at least 2 months.

Previous studies have shown that determining sex of adult white-winged doves (Zenaida asiatica) by cloacal characteristics is highly reliable (90%), while using plumage characteristics and body weights are less so. The drawback of the cloacal technique is that the procedure requires use of a modified nasal speculum to probe the cloacal area, which could possibly cause injury to the bird. We hypothesized that females have a wider pelvis than males for the passage of eggs, which should be quantifiable, thereby providing a means of separating adult males and females. We measured pelvic spread (distance from tip to tip of pelvis) of adults (n = 249). Additionally, body masses were taken for a subset (n = 215) of the doves. Sex was positively determined by either cloacal examination of live birds or gonad examination of dead birds. Mean pelvic spread of males was significantly less than that of females. Whole body mass was not correlated with pelvic spread for either sex. Accuracy of the pelvic sp...

Our objective was to use the 50%-core-area estimation to measure size of home range of urban-breeding white-winged doves (Zenaida asiatica) from two ecoregions in Texas. We collected data on locations using subcutaneously implanted radiotransmitters on 40 white-winged doves in Kingsville, Kleberg County, during 2000, and 40 and 39 white-winged doves in Waco, McLellan County, during 2002 and 2003, respectively. We calculated size of home ranges using bivariate-normal methods. We compared size of home range from 50%-core-area estimations within and between sites, and by sex, using two-sample t-tests following log10 transformation of data to meet the assumptions of normality and homoscedasticity. Generally, estimated size of 50%-core-areas differed significantly between sites but not within sites.

Our study determined if white-winged doves (WWDs; Zenaida asiatica asiatica) breeding in locations where environmentally persistent contaminants occur in the Lower Rio Grande Valley of Texas have levels of contaminants that can hinder reproduction. During summer 2003, 70 (32 males, 38 females) adult WWDs were collected from 8 at-risk sites. Liver tissues were analyzed for ten major and trace elements and muscle tissues were analyzed for 20 organochlorine compounds, 21 polychlorinated biphenyl congeners, and toxaphene. Samples were compared to ten (five male, five female) captive-raised control WWDs. Arsenic, chromium, and lead were not detected or were below the detection limit, whereas copper, zinc, selenium, mercury, nickel, cadmium, and silver were detected in 70 (100%), 70 (100%), 52 (74%), 21 (30%), 4 (6%), 1 (1%), and 1 (1%) WWDs, respectively. None of the detected elements had significant sampling site, bird gender, or Site x Gender interactions, and each occurred at background levels. Toxaphene and polychlorinated biphenyls were not detected, whereas DDE, dieldrin, gamma-BHC, and chlordane were detected in 13 (19%), 5 (7%), 2 (3%), and 1 (1%) field-collected WWDs, respectively, but all concentrations occurred at background levels. Concentrations of elements and compounds in field-collected WWDs did not significantly differ from those of the controls. Correlations between leukocyte counts and detectable contaminants generally indicated no correlation between each percentage of leukocyte type present and levels of selenium, copper, zinc, mercury, or DDE detected. One sample that had 0.072 mug/g dieldrin exhibited a low lymphocyte percentage (66%) out of only five samples. Comparisons could not be made with gamma-BHC, chlordane, or the other elements that had a low number of samples with detectable levels. Overall, concentrations of elements and organochlorines found in WWDs were below levels known to impair reproduction and survival in birds.

Agricultural intensification is a key factor in the decline of many avian populations throughout the world, yet the exact mechanisms that contribute to these declines are relatively unresolved, especially for seed-eating species. We tested the hypothesis that forage quality, particularly protein content, limits productivity in birds consuming diets dominated by agricultural grains and lacking in native forages. We used white-winged doves (Zenaida asiatica) because columbids are highly granivorous and white-winged doves have declined in areas dominated by grain agriculture. We randomly assigned 52 pairs of captive doves to 1 of 2 treatments: we fed one treatment sorghum (Sorghum bicolor) and the second sorghum plus native seeds (croton [Croton sp.] and native sunflower [Helianthus sp.]). Birds with access to native seeds fledged 123% more young per pair, with young weighing 32% more at fledging than those fed only sorghum. Doves with access to native seeds selected a diet consisting of 43% sorghum, 32% croton, and 25% sunflower. We conclude that agricultural grains, which typically have high metabolizable energy and low to moderate protein concentrations, are not sufficient for normal productivity of white-winged doves. The lack of native forages with sufficient metabolizable energy and protein content may be a factor in the declining productivity of white-winged doves in the lower Rio Grande Valley of Texas, USA, as well as other species in regions dominated by agriculture.

We present a simulation model for risk assessment of the impact of insecticide inhibitors of cholinesterase (ChE) applied in irrigated agricultural fields on non-target wildlife. The model, which we developed as a compartment model based on difference equations (Δ t = 1 h), consists of six submodels describing the dynamics of (1) insecticide application, (2) insecticide movement into floodable soil, (3) irrigation and rain, (4) insecticide dissolution in water, (5) foraging and insecticide intake from water, and (6) ChE inhibition and recovery. To demonstrate application of the model, we simulated historical and “worst-case” scenarios of the impact of ChE-inhibiting insecticides on white-winged doves ( Zenaida asiatica ) inhabiting natural brushland adjacent to cotton and sugarcane fields in the Lower Rio Grande Valley of Texas, USA. Only when a rain event occurred just after insecticide application did predicted levels of ChE inhibition surpass the diagnostic level of 20% exposure. The present model should aid in assessing the effect of ChE-inhibiting insecticides on ChE activity of different species that drink contaminated water from irrigated agricultural fields, and in identifying specific situations in which the juxtaposition of environmental conditions and management schemes could result in a high risk to non-target wildlife.

We monitored nesting home ranges of White-winged Doves (Zenaida asiatica) in Waco, Texas using field-implanted, subcutaneous radio transmitters. Mean nesting home-range size differed by gender (75.7 km2 for females, 31.9 km2 for males, P = 0.17). Mean nesting home-range for all individuals of known gender differed by year (75.6 km2 for 2002, 32.0 km2 for 2003, P < 0.001). Within-year mean nesting home ranges for individuals differed by gender for 2002 but did not for 2003. We received reports of 35 band recoveries (2.3% of those banded) through March 2004. Distance moved did not differ by year, gender for adults, or for gender by age. Distances of recoveries from banding sites ranged from 0 to 477.4 km.

We evaluated an unverified index (auditory counts) used to estimate breeding populations of white-winged doves (Zenaida asiatica) in Texas, USA. Our objectives were to determine optimal survey time of day, year, and count duration, determine if a relationship existed between number of calling doves and population size (nest and dove density), and evaluate an electronic counter to estimate breeding density. We collected data on 15 sites in the Lower Rio Grande Valley of Texas during May–August of 2002–2003. Peak calling occurred between mid-May and late June during 0600–0800 hours. We detected about 60% of calling doves during 2-minute auditory counts. Estimates of breeding doves (pairs ha−1) as determined by auditory counts were positively correlated with both population density (r > 0.90, P 0.94, P 0.77, P 0.92, P < 0.04). Howev...

We respond here to a critique of our paper (Small et al. 2004b) regarding the methodology used to implant subcutaneous transmitters in white-winged doves (Zenaida asiatica). We agree with Mulcahy (2006) that more information regarding the methodology we used would have been appropriate. However, we refute the contention that we could not have followed the surgical protocol we cited and that protocols were not sterile. We believe this misinterpretation of our methods comes from a failure to note some of the finer points reported in our methodology. We address each issue made by Mulcahy (2006) in this response.

Using field-implanted subcutaneous radio transmitters, we monitored the breeding biology of White-winged Doves (Zenaida asiatica) in a recently colonized urban area (Waco, Texas). We implanted transmitters in June 2002 (n = 39; 16 males, 23 females) and February and March 2003 (n = 40; 17 males, 17 females, 6 unknown sex), and tracked radio-tagged doves every 3rd day until transmitters no longer functioned (90–120 days). We tracked 26 doves to 36 nests in nine tree species. The maximum number of nesting attempts was four. Nest success of first and second nesting attempts was 62 and 24%, respectively, and overall nest success for both years combined was 52%. Mean nest height—as a proportion of tree height—ranged from 0.31 to 0.75. Urban White-winged Doves had an extended breeding season; nesting attempts occurred both before and after the traditional dove breeding period in native brush habitats of the lower Rio Grande Valley of Texas. Field-implantation of subcutaneous radio transmitters was a vi...

Sixty-three Eurasian collared-doves (ECDs) (Streptopelia decaocto) from Florida were examined for parasitic helminths from June to December 2001. Nine species of helminths were identified (5 nematodes, 2 cestodes, and 2 trematodes). The most prevalent helminths were Ascaridia columbae (73.0%), Fuhrmannetta crassula (28.6%), Ornithostrongylus quadriradiatus (12.7%), and Bruscapillaria obsignata (11.1%). The helminths with the greatest mean intensity were Tanaisia bragai (13.5), A. columbae (9.3), and O. quadriradiatus (7.1). In Florida, the mean intensity of A. columbae in ECDs (9.3) was similar to that found in white-winged doves (Zenaida asiatica) (9.1) (P = 0.461), and both the intensities were significantly higher than that in the native mourning doves (Zenaida macroura) (3.7) (P = 0.001 and 0.005, respectively). Fuhrmannetta crassula is reported for the first time in columbids from Florida.

We experimentally evaluated alternative techniques of attaching radiotransmitters to captive white-winged doves (Zenaida asiatica) in Kingsville, Texas during 1998. Our evaluation consisted of monitoring physiological, pathological, and behavioral parameters in doves subjected to 6 radiotransmitter attachments (backpack harnesses, adhesive, subcutaneous implants, intracoelomic implants, subcutaneous surgeries without implantation, intracoelomic surgeries without implantation). We analyzed physiological parameters across 2 pretreatment and 4 post-treatment periods using a model-selection approach of mixed-effect models. Birds did not differ in physiological variables among treatment groups and a control. Time-activity budgets analyzed using nonparametric Friedman's tests did not differ in any activity category among treatment groups and a control. Subcutaneous implants were the most effective method of attachment based on retention rates, lack of mechanical difficulties associated with external attachment techniques, and minimum levels of pathology reported following necropsies.

The haemoproteid community of 171 eastern white-winged doves (Zenaida asiatica asiatica) from the expanding Texas population was examined using thin blood smears. During summer 1997, heart blood was taken from doves within their historical breeding range (Lower Rio Grande Valley of Texas), an intermediate region (San Antonio and surrounding area), and the new breeding periphery (north central to southeast Texas). Two species were found: Haemoproteus columbae and Haemoproteus sacharovi. Infracommunities rarely occurred in heart blood, as only 20 of 132 infected doves demonstrated gametocytes of both species. Overall prevalence of H. columbae and H. sacharovi was 77 and 15%, respectively. Prevalence of H. columbae was higher in the Lower Rio Grande Valley (LRGV) and intermediate regions than at the periphery, higher in adults than juveniles, and similar between males and females. Prevalence of H. sacharovi was lower in the LRGV than intermediate and peripheral regions, similar between juveniles and adults, and higher in females than males. Mean density of H. columbae and H. sacharovi was 15.9 +/- 2.7 and 0.3 +/- 0.1 (mean +/- SE per 3,000 erythrocytes), respectively. Overall mean abundance of H. columbae and H. sacharovi was 12.2 +/- 2.2 and 0.04 +/- 0.02, respectively. Mean abundance of H. columbae was higher in the LRGV and intermediate regions than at the periphery and was similar between host age and between host sex; H. sacharovi was similar among regions, host age, and host sex. This study emphasizes the importance of using prevalence, density, and abundance data to assess haemoproteid community structure and pattern.

A cross-sectional survey was conducted in order to determine the seroprevalence and to identify some factors associated with the presence of antibodies against Salmonella enterica subsp. enterica serovar Gallinarum-Pullorum in white-winged (Zenaida asiatica) and mourning doves (Zenaida macroura) from hunting areas of Northeast Mexico. From September to October 2006, 201 serum samples were analyzed with the seroagglutination test. The overall seroprevalence of S. enterica subsp. enterica serovar Gallinarum-Pullorum was 26.3%, and was similar for white-winged doves (26.4%) and mourning doves (26.1%), but higher for juveniles (30.8%) and females (34.6%). Seroprevalence was associated with the weight of the doves (prevalence ratio [PR]=1.52, P0.0001) and the municipality where the doves were hunted (PR=1.31, P0.0001). This survey study emphasizes the need to conduct similar studies on wild birds to determine the risk of S. enterica subsp. enterica serovar Gallinarum-Pullorum to commercial flocks. In addition, to the best of our knowledge this is the first report of the serological evidence suggesting infection with S. enterica subsp. enterica serovar Gallinarum-Pullorum in wild white-winged and mourning doves.