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Análisis previos sobre los avances en la ornitología Neotropical han destacado a Paraguay como uno de los países prioritarios para el desarrollo de estudios, dada su riqueza de aves y el reducido número de publicaciones disponibles. En este artículo examinamos las contribuciones publicadas sobre la ornitología del Paraguay en un periodo de 25 años desde 1995 hasta el 2019, dividiendo estas publicaciones en quinquenios y en 11 áreas del conocimiento en la ornitología. Analizamos un total de 203 publicaciones, entre ellas artículos científicos y libros. Artículos referentes a distribución y ocurrencia de especies corresponden a casi el 51%, seguidos por aquellos relacionados a conservación (13%) e historia natural (12%). En promedio, ocho contribuciones por año han sido publicadas en los 25 años. En el último quinquenio, hubo un aumento de publicaciones ornitológicas en un 58% con relación al anterior quinquenio; así también ha aumentado hasta en un 93% las contribuciones por autores afiliados en el Paraguay y hasta en un 98% en estudios hechos exclusivamente con datos del Paraguay. Gran parte de este aumento se debe a contribuciones de unos pocos autores, y mayormente como notas cortas. En cuanto a las regiones ornitogeográficas, Alto Paraná y Chaco Central son las más estudiadas, con un 42% y 31%, respectivamente. Más del 50% de las familias y 30% de los órdenes no han sido objetos de estudio en los últimos 25 años. Con este análisis, demostramos un aumen- to aún muy incipiente de la investigación ornitológica en el país; identificamos acciones que estarían apoyando su desarrollo, así como las dificultades, y orientamos las prioridades de investigación en el Paraguay.

Central-eastern Spain is characterised as being a flat and relatively open landscape, greatly used for agricultural purposes and with a high density of wind installations. This landscape also hosts a large population of the lesser kestrel (Falco naumanni), one of the species most threatened by collisions with wind turbines. During a ten-year period, we analysed bird mortality by recording deaths on three wind farms (WF), Cerro del Palo, Cerro Calderon and La Muela I, located in the province of Cuenca (Spain) and containing a total of 99 turbines. The aim of the study was to determine the variables associated with mortalities caused by these types of devices. Subsequently, the information obtained allowed a mitigation measure to be implemented for avoiding and minimising collisions. The procedure involved superficially tilling the soil around the base of turbines with a high collision rate. This measure was monitored for two years before and after implementation in order to compare its effectiveness, and involved making the areas around the turbines less attractive to kestrels by tilling and reducing the amount of vegetation and consequently the abundance of potential prey, mainly Orthoptera. If effective, the lack of prey would decrease the number of dead kestrels, as the birds of prey would need to search for food in other less dangerous areas (approximately 80 m away from the turbines). After monitoring the mitigation measure it was found that the number of collisions decreased by 75–100%. In fact, no collisions were registered during the two year period for all of the wind turbines with tilled surroundings. Based on these results it can be safely stated that this mitigation measure is an easy and inexpensive procedure that significantly and effectively reduces the number of kestrels that collide into wind turbines.

The phase of the moon can affect activity patterns of nocturnal animals, and may also affect visibility for motorists. However, surprisingly little is known about whether the risk of a wildlife-vehicle collision (WVC) is associated with lunar phase. We investigated the relationship between frequency of WVC at night and lunar phase for four large ungulate species that account for a high proportion of serious WVC along roads in agricultural and forested landscapes of two continents: wild boar Sus scrofa, roe deer Capreolus capreolus, and red deer Cervus elaphus in Castile and Leon, Spain, and white-tailed deer Odocoileus virginianus in New York State, USA. Three of the four species most frequently collided with vehicles at night during the full moon phase of the lunar cycle; this pattern was evident throughout the year but was stronger during some months. For roe deer, the species for which WVC was most closely associated with the lunar cycle, the frequency of WVC was 71.3% greater during the full than new moon period. Our results indicate that rates of ungulate WVC at night cycle on a period of a lunar month, which has implications for traffic safety planning and for motor vehicle collision emergency response preparation.

Birds inhabiting urban areas have to deal with high levels of ambient noise. Some species show a certain song flexibility that enables them to reduce noise interferences in their communications. This vocal adjustment usually implies an increase in the minimum frequencies of songs. Since urban noise is mainly made up of low frequencies (about 2.5–3.5 kHz), song of species that sing at higher frequencies could be less susceptible to being masked by anthropogenic noise. This study explores whether such species also show any kind of adjustment to noisy environments. For this purpose, the spectral and temporal parameters (note duration, maximum and minimum frequency and diversity) of the song of the European Wren Troglodytes troglodytes were analysed in three different environments (urban, periurban and rural). To evaluate the impact of noise on the vocalizations, a specific acoustic descriptor of song variability was developed. Song variability increased along the urban noise gradient from rural to ...

Since domestication, a large number of livestock breeds adapted to local conditions have been created by natural and artificial selection, representing one of the most powerful ways in which human groups have constructed niches to meet their need. Although many authors have described local breeds as the result of culturally and environmentally mediated processes, this study, located in mainland Spain, is the first aimed at identifying and quantifying the environmental and human contributions to the spatial structure of local breed diversity, which we refer to as livestock niche. We found that the more similar two provinces were in terms of human population, ecological characteristics, historical ties, and geographic distance, the more similar the composition of local breeds in their territories. Isolation by human population distance showed the strongest effect, followed by isolation by the environment, thus supporting the view of livestock niche as a socio-cultural product adapted to the local environment, in whose construction humans make good use of their ecological and cultural inheritances. These findings provide a useful framework to understand and to envisage the effects of climate change and globalization on local breeds and their livestock niches.

Anthropogenic noise in urban environments is a major challenge for those species that depend on the transmission of acoustic signals to communicate. To avoid being masked by background noise, some bird species are able to make adjustments in their songs. Studies on vocal adjustment for tropical birds are still scarce and are of interest since both the urban structure and the vegetation associated with urban habitats differ significantly with respect to the cities of temperate climates. In this research we studied the changes in the song parameters of the pale-breasted thrush (Turdus leucomelas) in an urban environment of the metropolitan area of Belém (Brazil). To this end, bird songs were recorded and ambient noise was measured between September and November 2008, in three different acoustic environments (urban, suburban and rural) along an urban gradient. The songs of 12 individuals per area were selected (a total of 36). Possible differences between song parameters were analyzed by ANOVAs. To assess the noise impact on bird song, we only considered the spectrum of environmental noise within the range of vocalizations of the species. In general, birds of urban habitats presented songs with higher maximum frequencies and with a wider range of notes, than their counterparts in suburban and rural areas. The differences were more pronounced in relation to rural areas. No differences in the minimum frequencies, the concentration of energy, or the average duration of the notes were found. These results differ from other studies and could possibly indicate variations in the way birds try to succeed in habitats with high ambient noise. It is necessary further exploration on the role of these changes in the effective improvement of intra-specific communication for the species in such environments.

Influence of new irrigated croplands on wild boar (Sus scrofa) road kills in NW Spain .— In recent decades, wild boar populations have increased both in number and distribution. This rise is partly related to the increase in cropland devoted to maize (Zea mays) cultivation, as wild boar find food and refuge in these areas. This population expansion has led to an increase in the number of wild boar vehicle collisions (WBVCs). The goal of the present study was to evaluate a set of spatio–temporal factors that influence WBVCs related to maize crops on the Northern Spanish Plateau (the region of Castile and Leon). We compared the maize pattern with the factors related to total WBVC numbers. We observed that whereas the total occurrence of WBVCs usually increased with forest cover and speed and traffic volumes, maize areas were one of the main explanatory variables in plateau models. To avoid collisions in these areas in future, a number of mitigation measures are outlined.

Assessing use of resources across resource gradients and over time is necessary for determining factors that influence the natural distribution of birds. We analysed the pattern of availability of food resources, the use of food resources and the influence of food availability on reproduction and demography for the Austral Parakeet (Enicognathus ferrugineus) in two southern temperate forests of Argentine Patagonia. The abundance of Austral Parakeets in Nothofagus pumilio forests co-dominated by Araucaria araucana was generally higher and fluctuated more than abundance of populations in monospecific N. pumilio forest. This appears to be related to A. araucana providing a larger but more variable food resource. Austral Parakeets responded quickly to changing availability of resources by modifying their diet if alternative food resources were available, and reproductive success also increased when seed availability was high. We found mixed forests to be a unique and important habitat for Austral Parakeets in the northern part of their range, and conservation management should recognise this special role that mixed N. pumilio–A. araucana forests play in Austral Parakeet ecology.

Se ha demostrado que algunas especies de aves son capaces de modificar sus cantos para evitar ser enmascarados por el ruido de fondo, un hecho particular que se enmarca dentro de la hipótesis de adaptación acústica al ambiente circundante. En este estudio se realizó un análisis de los parámetros físicos y temporales del canto de la Ratona Común (Troglodytes musculus) en tres ambientes acústicos diferentes (áreas urbana, periurbana y rural) dentro de la zona metropolitana de Belém (Brasil). Para evaluar el impacto acústico sobre el canto de la especie no se consideró el espectro completo del ruido ambiental sino sólo aquel que se encuentra en el rango de vocalización de la especie, que es el que potencialmente puede interferir en el canto. Algunos de los parámetros del canto, como la concentración de energía en relación a las frecuencias o la duración de las notas, se correlacionaron con los niveles de ruido ambiental. Las discrepancias entre los resultados obtenidos a partir de los niveles de ruido y de la zonificación urbana pueden ser una consecuencia de diferencias en la vegetación o en las características propias del planeamiento urbanístico de la ciudad de Belém. Tales correlaciones pueden ser un indicio de la adaptación acústica pero también puede haber otros factores que las expliquen. Si estos cambios se explicaran por los niveles de ruido ambiental, se requeriría una investigación orientada a demostrar que tales cambios contribuyen a una mejora efectiva de la transmisión del canto.

We report observations of the Austral Parakeet (Enicognathus ferrugineus) feeding on larvae in the northern part of its distribution in the austral temperate forests of Argentine Patagonia during the pre- and post-reproductive seasons. Larvae consumed were Aditrochus fagicolus (Chalcidoidea: Pteromalidae) in leaf galls of Nothofagus pumilio (79 observations), larvae from Homoptera, Lepidoptera, and Diptera in seed galls of N. pumilio (12 observations), and larval Nemonychidae (Coleoptera) in male cones of Araucaria araucana (69 observations). Our observations suggest Enicognathus ferrugineus could be more insectivorous than previously thought, perhaps to help meet their demand for high-quality food during the pre- and post-reproductive seasons.

Species that use vocal communication have difficulties in transmitting their messages in noisy habitats. The capacity to adapt songs to prevent them from being masked by noise could be a key factor for reproductive success in such environments. Previous research has demonstrated changes in several song parameters between rural and urban areas. In the present study we were prompted to check vocal adjustment along an urban gradient. The survey was carried out in the city of Salamanca (Spain), which owing to its small size has a strong physical gradient over a short distance. We recorded the songs of 27 common blackbirds (Turdus merula) and ambient noise at 13 sites. The choice of sites corresponds to different areas along this gradient: urban, periurban and rural zones. Anthropogenic noise increased from the rural to urban recording sites. Differences in vocalizations were found in both the maximum and minimum frequencies among the three areas. The blackbird can shift its entire vocalization to avoid masking by ambient noise, which occurs mainly at low frequencies. Song frequencies showed a graded response to ambient noise. Urban gradients in small cities are steep and strong, but the degree of isolation is low. In this context, vocal adjustment is more likely to be possible by means of behavioural plasticity although environmental pressure could lead to genetic changes in more isolated areas. Other changes along the urban gradient modify both ecology and population parameters of the blackbirds and could also be another possible explanation for song variation.

Roadkill is one of the most prominent causes of wildlife mortality. Much research effort has focussed on collisions with ungulates because of traffic safety. However, studies about large carnivore roadkills are scarce despite vehicles being a main cause of mortality. The absence of studies can be explained in part because of difficulties in obtaining sufficient sample sizes. We collected data from locations of 82 wolf roadkill sites in the Castilla y Leon Region, northwest Spain. We evaluated different models to characterise collision localities using logistic regressions with corrections for rare events. The best models included traffic and human disturbance parameters. Landscape variables did not improve predictive power. Fencing was a decisive key predictor; roadkill was proportionally higher along fenced highways than on similar major roads that lacked fences. Wolf–vehicle collisions were more common in agricultural areas, although wolf densities were lower in these zones. Both the higher density of important roads and a greater proportion of roaming wolves on the plateau may explain this pattern.

Diet composition of the Barn Owl Tyto alba was studied in agricultural landscapes in Thessaly, Greece, for 3 years (2003–05). A total of 852 Rattus spp. individuals were identified from 10 065 pellets, which accounted for 2.9% by frequency and 27.4% by biomass of 29 061 prey items. Rattus spp. were more numerous in Barn Owl pellets during winter months than in summer. We suggest that this difference was due to a shift in relative prey availability and an increased need for energy by the Barn Owl during the colder months. Comparisons between Thessaly and 15 other areas showed differences in prey availability between islands and mainland Greece. Microtus spp. were absent from all island diets except one, and some islands had greater species richness.

Highly pathogenic avian influenza (HPAI) subtype H5N1 continues to circulate across Eurasia and Africa since its unprecedented rapid spread in 2005. Diffusion by wild bird movements has been evidenced in the European Union in 2006 and 2007. Spain is an important wintering quarter for aquatic birds from northern latitudes, so identifying the critical areas and species where an outbreak is prone to happen is necessary. This work presents an assessment of the risk of introduction of H5N1 HPAI in Spain by aquatic wild birds estimating a relative risk value per province. For this purpose, an assessment of the release and exposure to the risk of infection with H5N1 HPAI of 25 selected water bird species has been carried out. Parameters considered in the assessment include H5N1 HPAI notifications from 2006 to 2008 and factors that favour the occurrence or persistence of H5N1 HPAI (wetlands' surface, low temperatures), together with aquatic wild birds' movements parameters (departure, destination, stop-overs, abundance) and parameters relative to the susceptible population in Spain poultry density and wild aquatic abundance. Results show the relative risk for each Spanish province of experiencing H5N1 HPAI introduced by wild aquatic birds helping to identify higher risk areas. © 2009 Blackwell Verlag GmbH.

Over an 18-month period regular counts were made of the water birds inhabiting lakes and ponds in the Lanin National Park in Argentinean Patagonia. A total of 130 bird surveys were conducted on 21 wetland areas, detecting 6,364 individuals belonging to 27 species from nine families. The most abundant and frequent species were Cloephaga poliocephala, Anas flavirostris, Fulica armillata and Fulica. leucoptera. Species richness was higher in spring and summer than in autumn and winter, involving 31 and 27 expected species, respectively. In contrast, bird abundance did not differ between season. The presence and abundance of bird species with respect to the surface area of the water body highlights the importance of certain lakes in particular. Thus, small water bodies (

Roads play an increasingly important role on the biology of wild animals living their natural surroundings, especially during the breeding season. The present work examines predation on artificial nests with respect to roadsides and the distance of such nests distance from roads in a woodland area in Western-Central Spain. Roads were classified according to traffic density, and field work was carried on from April to July in 2004 and 2005. A total of 720 nests were placed and 471 (65.4%) were disturbed by predators during the study. Nest fate was associated with the type of road ( P P = 0.001). Such disturbances were greater ( P = 0.02) at nests placed farther away (>25 m) from roads with high traffic density than on those located close to roadsides. Roads with a medium or low traffic density had a higher incidence of nest predation ( P = 0.012 and 0.025, respectively) than nests distant from them. We conclude that predators do not use roads with high traffic density as travel corridors, and nor do they concentrate their foraging activities along them. Roads with a medium and low volume of traffic offer a greater probability of collisions with wild animals, and hence predators often use this type of roads to scavenge their food. We caution investigators to take into account the distances of nests to different types of edge when attempting to evaluate avian nesting success.

Abstract The small mammal community in 21 localities of north-western Spain was evaluated in the light of land use composition. The two geomorphologic categories characterising the study area, the main use of the land (arable/pastoral) and main crop types of each sampling locality were used as potential predictors of the relative abundance of five common small mammal species. The Common vole, Microtus arvalis showed a weak relationship with land uses, probably due to the recent colonisation process this species experienced in the study area. The relative abundance of the Algerian mouse, Mus spretus and the Lusitanian pine vole, Microtus lusitanicus was best explained by models built at the broadest regional scale, the former being more abundant in the eastern area, the latter in the western area. The Greater white-toothed shrew, Crocidura russula showed a positive relationship with grassland coverage, whilst the Wood mouse, Apodemus sylvaticus benefited from increasing proportions of fallow lands within the landscape. These two species are then expected to respond positively to those agri-environmental schemes including the increase of fallows and grassy vegetation within the arable landscape (EU recommendations). However, further efforts are needed to predict, at least qualitatively, the response of other small mammal species to the changing farmed landscape. This is especially true for two endemic species occurring at this area: the Cabrera vole, Microtus cabrerae and the Lusitanian pine vole, and for which this kind of information is almost absent.

The effect of traffic noise on the breeding density of 20 passerine species was examined over a 2-year period in three different road types passing through pasture-woodlands in western-central Spain. No statistically significant differences were observed during the 2 years studied. An average of 19.6 birds/10 ha was recorded for the low-traffic road (LT), 21.7 birds/10 ha for the medium-traffic road (MT) and 19.1 birds/10 ha for the high-traffic road (HT). A total of 11 species (55%) did not show any statistically significant differences in breeding density among the different types of roads. By contrast, other species, such as the Blackbird, the Iberian Shrike and the Linnet, did point to differences between the MT and HT roads. House and Rock Sparrows, as well as the Corn Bunting, showed higher breeding densities near the HT road. The opposite effect was observed for the Wheatear, the Iberian chiffchaff and the Woodlark, for which high breeding densities were recorded in the vicinity of the LT road. Our results suggest that traffic noise constitutes a serious problem for at least 15% of the breeding bird community.

Use of electric power poles as nesting supports by birds was surveyed in the northern Spanish plateau, a deforested and nest-site sparse area. A total of 4336 poles of five different designs was sampled and the nesting rate was 4.99%. White stork ( Ciconia ciconia ) is the most frequent nesting species using the structures with 79.2% of the total bird nest. Crows and ravens ( Corvus corax and Corvus corone ) have 15.7% of the nests, and raptors have 4.6%. Pole types A and E are favorite supports for nesting and those near irrigation croplands or wooded-grasslands are preferred by all bird species.

The goal of the present study was to assess which variables influence the distribution of birds in urban parks. Twenty parks were studied in a city on the Spanish high plateau during the breeding season, and relationships among park characteristics, bird richness, and individual bird presences were established. The park area and tree cover accounted for 73.1% of the variation in bird richness. Although area size was the best predictor of species richness (65% of the variation), some species did not seem to be related to this variable but rather to others, such as vegetation and the degree of park isolation with respect to other areas. Contrary to what is normally expected, the distance from our parks to the river did not influence their bird species richness. © TÜBİTAK.

Great bustard (Otis tarda) populations in Spain are located mostly in cultivated areas during winter. The birds concentrate in large flocks and feed on cultivated plants. This paper reports two types of bustard-caused damage which occur in cereal, lucerne and vetch crops in west-central Spain, as a result of grazing and other bird activities such as display. Field work was carried out between 1994 and 1995. Damage to cereal crops was caused during germination and early seedling growth or to young plants, although plants were able to recover from this by regrowth and the overall yield was not reduced. Vetch crops were damaged in localized areas, but these recovered and were useful for forage enrichment or as grain. However, the damage to lucerne plots, although local, was extensive, resulting in yield losses of 23–31% with respect to the total production.

The breeding biology of the Monk Parakeet (Myiopsitta monachus monachus) was studied in Punta Blanca, central Argentina (34° 56’ S, 57° 39’ W). Observations on 9 communal nests (13 breeding chambers) were made dur‐ing 1988 and 1989. The median date of the first egg for each year was Hand 31 October (the median for 2 years was 16 October). Clutch size ranged from 5 to 12 eggs, averaging 6.9. Incubation took 23.6 days and hatching was asynchronous. Mean hatching success for clutches was 52.2%. Only 17% of the nestlings fledged. Only 8.9% of the total eggs laid resulted in fledglings. Predation by Opossums (Didelphis) and Black Rats (Rattus) was the main cause of mortality at nests (82%), but 17.9% of the nestling mortality was due to intraspecifics attacks, including sibling aggression.

We studied the wintering of European Starlings by means of ringing recoveries since 1960 and the distribution of roosting sites in the last fifty years. An overall decrease was found in the number of roosts as well as in wintering birds. However, this is due to a a considerable decrease in the south and east, whereas in the north and northeast the number of wintering birds seems to be stable ore even lightly increasing. This geographical difference can be correlated with the decline of breeding populations in North and Central Europa and/ore with the growing populations in France and Belgium respectively. In the last decade, the number of urban roosts in Spain increased.

The births of brown brocket deer ( Mazama gouazoubira) in a secondary lower montane forest called "yunga" in northwestern Argentina were compared with rainfall. Analyses were performed with rainfall and flower-fruit fall in an attempt to determine the possible importance of these seasonal variables in birthing. The births were not directly correlated with rainfall, but rather with the flower and fruit fall of exotic plant species. This may be related to favor the development of fawns, which eat the new and more digestible plant parts, accessible one month after their births.The non-seasonal births observed around the year could be related to the selection by the deer of some plant species that have been introduced into the region (Prunus, Morus and Psidium), have a longer fruiting span than the scarce native plant species.

The interaction between native fishes and salmonids introduced in Patagonia at the beginning of the 20th Century, developed at the same time as the environmental change. The phenomenon of global warming has led to the formulation of predictions in relation to changes in the distribution of species, in the latitudinal dimension, both at intralacustrine, or small streams levels. The aim of the present work includes three main objectives: a) to compose a general and updated picture of the latitudinal distribution range of native and alien fishes, b) to analyze the historical changes in the relative abundance of Percichthys trucha, Odontesthes sp., and salmonids in lakes and reservoirs, and c) to relate the diversity and relative abundance of native and salmonid fishes to the environmental variables of lakes and reservoirs. We analysed previous records and an ensemble of data about new locations along the northern border of the Patagonian Province. We compared current data about the relative abundance of native fishes and salmonids in lakes and reservoirs, with previous databases (1984–1987). All samplings considered were performed during spring-summer surveys and include relative abundance, as proportions of salmonids, P. trucha, and Odontesthes sp. For the first time, we found changes in fish assemblages from twenty years back up to the present: a significant decline in the relative abundances of salmonids and an increase of P. trucha. We studied the association between the diversity and relative abundance of native and salmonid fishes and the environmental variables of lakes and reservoirs using Canonical Correspondence Analysis. Relative abundance showed mainly geographical cues and the diversity relied largely on morphometric characteristics. Relative abundance and diversity seem to have a common point in the lake area, included into the PAR concept. Native abundance and alien diversity were negatively related with latitude. Greater native diversity was observed in lakes with high PAR compared with salmonids. Historical changes such as southward dispersion, relative abundance changes, and geographical patterns for relative abundance and diversity are basic concepts needed not only in future research but also in management design for Patagonian fish populations., Facultad de Ciencias Naturales y Museo

We provide new information on all birds known from San Rafael National Park, Paraguay. Ornithological records from the period 1997 to 2006 have been reviewed, adding 112 new species to the reserve's avifauna. We provide data on the presence of 405 species in seven basic habitats types, and on their relative abundance. Biogeographically, San Rafael has a mixed avifauna, consisting of 70 Atlantic Forest endemic species, two Mesopotamian Grassland endemics, and many with a wider distribution in South America. At least 12 species are threatened and 16 near-threatened, including important populations of Dryocopus galeatus, Platyrinchus leucoryphus, Alectrurus tricolor and Xanthopsar flavus. We provide brief comments on records of these 28 species within the study site. The avifauna of the reserve is one the most important in Paraguay, due to its high diversity and endemism. At the same time, it is under great threat and its viability is at risk unless urgent actions are taken. Fragmentation of the Atlantic Forest in Paraguay has left the San Rafael block almost totally isolated from other forests. The degradation of its forests through selective logging and clearance for agriculture still has severe impacts, as do hunting and frequent fires in grasslands and forests. Unfortunately, the legal situation of the National Park is extremely precarious, creating great uncertainty and problems for its conservation.Aqui relatamos nuevas informaciones sobre todas las aves conocidas hasta el presente dentro del Parque Nacional San Rafael. Se han revisado registros ornitológicos comprendidos entre los aãos 1997 y 2006, que han permitido aãadir 112 especies nuevas para la reserva. De esta manera, San Rafael tiene un total de 405 especies registradas. Para cada una de ellas se facilitan datos que documentan su presencia en siete tipos de hábitats básicos diferenciados, y de su abundancia relativa. Biogeográficamente, la avifauna de San Rafael es una mezcla que está compuesta por 70 especies endémicas del Bosque Atlántico, dos endémicas de los Pastizales de la Mesopotamia, y el resto, son de distribución más amplia en Sudamérica. Al menos, 12 especies están amenazadas y 16 casi-amenazadas, incluyendo poblaciones importantes de Dryocopus galeatus, Platyrinchus leucoryphus, Alectrurus tricolor y Xanthopsar flavus. De éstas 28 especies, se proporcionan comentarios breves sobre sus registros en el área de estudio. La avifauna de la reserva resulta una de las más importantes dentro del Paraguay, tanto por su mayor diversidad y presencia de endemismos, como por ser una de las áreas con alto potencial para mantener la biodiversidad, al tiempo que se encuentra sometida a fuertes amenazas que ponen en peligro su viabilidad en caso de no tomarse medidas urgentes. La alta fragmentación del Bosque Atlántico dentro del Paraguay, ha dejado al bloque de San Rafael prácticamente aislado de otros bosques. La degradación de sus bosques por tala selectiva y desmonte para agricultura son aún grandes impactos dentro de sus límites, así como la caza furtiva y la quema frecuente inducida de pastizales y bosques. Desafortunadamente, la situación legal del Parque Nacional es extremadamente precaria, generando así gran incertidumbre y dificultad para su conservación.

This work discusses the possibilities of direct and indirect contact across Central Asia, between migratory bird populations from the Iberian Peninsula, Southwestern Eurasian and Eastern Asian countries. This fact should be considered when preparing surveillance studies for highly pathogenic avian influenza viruses. Records were checked from birds ringed or recovered between 1980 and 2002 in the Iberian Peninsula, an important wintering area for waterfowl in the European Union. This study only addresses migrations covering more than 5000 km and exclusively to or from Asia. A total of seven species have developed migratory routes between Europe and the Caspian Sea/Central Asia in the following proportions to the total of birds recovered: Podiceps nigricollis (17%), Anas penelope (11.1%), A. clypeata (2.17%), A. platyrhynchos (1.86%), Pluvialis squatarola (33.33%), Calidris ferruginea (1.36%) and Sterna sandvicensis (0.67%). These recovery rates suggest the possibility of interchange - at the Central Asia and Caspian breeding groundsbetween the populations originating in Europe and those from Southeast Asia. Over the following seasons, through direct migration, misorientation or, as frequently observed in certain duck species, through a phenomenon of abmigration, some birds with a priori Asian wintering quarters could conceivably escort their "European" brethren to this continent and thus contribute to the propagation of avian flu to so far virus-free areas. Este trabajo señala las posibilidades de que existan contactos directos e indirectos, a través de Asia Central, entre poblaciones de aves migratorias de la Península Ibérica, y países de Asia del este. Este hecho debería ser considerado en los planes de vigilancia del virus de influenza aviar altamente patógeno. Se han cotejado las recuperaciones procedentes de aves anilladas o recuperadas en la Península Ibérica desde 1980 hasta 2002, considerando solamente aquellos individuos que tuvieron un desplazamiento superior a 5000 km, y en una dirección desde o hacia Asia. Un total de siete especies desarrollan rutas migratorias entre Europa y el mar Caspio/Asia central en las siguientes proporciones respecto al total de recuperados: Podiceps nigricollis (17%), Anas penelope (11,1%), A. clypeata (2,17%), A. platyrhynchos (1,86%), Pluvialis squatarola (33,33%), Calidris ferruginea (1,36%) y Sterna sandivicensis (0,67%). Las recuperaciones demuestran la posibilidad de confluencia entre las poblaciones que provienen de Europa y las del sureste asiático en las zonas de cría de Asia central y la región del Caspio. En próximos inviernos, y debido a fenómenos de migración directa, abmigración o desorientación, algunas aves cuyas zonas de invernada son a priori asiáticas, podrían acompañar a sus congéneres "europeos" a este continente y contribuir a la propagación de la gripe aviar hacia zonas libres del virus.

From 1993–1998, we monitored a 24.1-km long concrete water canal in northern Spain for drowned mammals. Along the canal, 14 concrete bridges and 9 small bridges permitted crossing by humans and livestock. Our objective was to test whether those bridges could be used as passages for wild animals to prevent drowning. We used tracks recorded in sand on bridges to identify species passing. Of the bridges, 65% were used by wild mammals; the 9 small bridges accounted for 57% of crossings by wild animals. Wild and domestic canids (Canis lupus, C.l. domesticus, Vulpes vulpes) were the main users (85%), followed by wild ungulates (mainly wild boar, Sus scrofa) at 71% of the crossings. Proximity to a mountain slope did not increase crossing in deer species, but did not hinder wild boars, foxes and wolves from doing so. Up to 88.1% of the wild mammalian species selected passages that were close to scrubland or forest. Of the drowned animals observed, 70% were dogs and livestock. More roe deer (Capreolus capreolus) drowned than other species, and 73% drowned between April and October. Throughout the year, 6.5% of wild boars fell into the canal . Foxes were the main species crossing the canal, but accounted for only 2.1% of drowned species. We recommend that the following action should be taken to reduce drowning: (1) bridges that are simpler and rustic in design should be constructed and (2) water catchments should be dug into the forest to provide water, so that animals do not need to use the canal as a water source or need to cross it to reach the river.

We discuss the contribution of ultraviolet (UV) renormalons in QCD to two-point functions of quark current operators. This explicitly includes effects due to the exchange of one renormalon chain as well as two chains. It is shown that, when the external euclidean momentum of the two-point functions becomes smaller than the scale $\Lambda_L$ associated with the Landau singularity of the QCD one-loop running coupling constant, the positions of the UV renormalons in the Borel plane become true singularities in the integration range of the Borel transform. This introduces ambiguities in the evaluation of the corresponding two-point functions. The ambiguities associated with the leading UV renormalon singularity are of the same type as the contribution due to the inclusion of dimension d=6 local operators in a low-energy effective Lagrangian valid at scales smaller than $\Lambda_L$. We then discuss the inclusion of an infinite number of renormalon chains and argue that the previous ambiguity hints at a plausible approximation scheme for low-energy QCD, resulting in an effective Lagrangian similar to the one of the extended Nambu-Jona-Lasinio (ENJL) model of QCD at large N_c., Comment: 39 pages, LateX, 8 Figures

The American mink Mustela vison has spread widely beyond its native North American range and is associated with problems for the conservation of native species because of its impact as both predator and competitor. We investigated the impact of feral mink on waterfowl in Lann National Park, south-west Neuqun, Patagonia, Argentina, an area in which the predator is currently expanding. Statistically significant differences were observed in the number of waterfowl species at lakes without mink (7.3±SE 0.7) compared to those with mink (4.0±SE 0.6). Overall abundance of birds observed per day was higher at lakes without (104.2±SE 20.6) than with mink (21.2±SE 22.3). The great grebe Podiceps major, speckled teal Anas flavirostris, Chiloe wigeon Anas sibilatrix and red-gartered coot Fulica armillata were more abundant on water bodies without mink, and flocks of the ashy-headed goose Chloephaga poliocephala were larger in areas without mink. Other species, such as the white-tufted grebe Rollandia rolland, coscoroba swan Coscoroba coscoroba, black-necked swan Cygnus melanocoryphus, cinnamon teal Anas cyanoptera, Andean duck Oxyura jamaicensis and Andean gull Larus serranus were never observed in areas harbouring mink. We conclude that at least 12 of the 25 waterfowl species observed are sensitive to the presence of the mink, either being absent or having a lower abundance where mink are present. © 2009 Fauna & Flora International.

The feeding response of feral rock pigeons (Columba livia) to wheat (Triticum aestivum) and barley (Hordeum vulgare) seed treated with the fungicide "Maneb" (manganese ethylene-bisdithiocarbamate) was assessed under aviary conditions. Bird preferences for dry or moist seed were also recorded. In all cases, non-treated (49.14 g birdE–1 dayE–1) rather than treated seed (32.97 g birdE–1 dayE–1) was selected, and wheat rather than barley (48.16 compared to 33.95 g birdE–1 dayE–1 respectively). Dry seed was consumed in preference to moist seed (47.53 g birdE–1 dayE–1 compared to 15.08 g birdE–1 dayE–1) —a preference noted both when treated and non-treated seed was consumed. The birds fed exclusively on treated seed showed a reduction in body weight; no significant differences were recorded in those fed either untreated or mixed seed. Water consumption was three times greater in pigeons fed exclusively on treated seed. Este trabajo evalúa la respuesta alimenticia que presenta la paloma bravía (Columba livia) a una dieta de semillas de trigo (Triticum aestivum) y cebada (Hordeum vulgare) tratadas con el fungicida Maneb (etilen-bisditiocarbamato de manganeso). La exposición al alimento se efectuó en períodos prolongados de tiempo y bajo las condiciones de un aviario. Aparte del efecto del tratamiento también se consideró la condición (seca o húmeda) de la semilla consumida. En todos los casos, las aves escogieron semillas no tratadas (49,14 g por ave y día) antes que las tratadas (32,97 g). El consumo de trigo fue más alto que el de cebada (48,16 g y 33,95 g, respectivamente). Las semillas secas (47,53 g) de ambas especies de cereal fueron consumidas más que las semillas húmedas (15,08 g), y esta preferencia persistió con el tratamiento o no de las mismas. Las palomas que se alimentaron exclusivamente de semillas tratadas mostraron una reducción en el peso corporal, pero no se encontraron diferencias estadísticamente significativas del peso entre aves que se alimentaron de semillas sin tratamiento y las que consumieron una mezcla de ambas clases. El consumo del agua fue tres veces más alto en palomas alimentadas exclusivamente con semillas tratadas.

A field study was carried out in the springs of 1988 and 1989 in deciduous oak forests of west-central Spain to assess the effects of two aerial sprayings with two different application rates of Cypermethrin, a synthetic pyrethroid, on several reproductive parameters (nest abandonment, nest success, clutch size, hatching success, nestling mortality, daily survival rate, and nestling weight) of the blue tit (Parus caeruleus). These variables were analyzed according to reduction of arthropod density in canopy trees after treatments and results were compared with a control plot (plot A) without application. The plot sprayed in 1988, with a dust formulation of cypermethrin at 75 g active ingredient (a.i.) per hectare (plot B), showed a nearly 100% mortality of lepidopteran larvae, the most important food resource for breeding blue tits, as well as for other arthropods. The drop in food supply in this plot coincided with the hatching or early nestling stage of the blue tit population. There were statistically significant differences between the control plot and plot B in nestling mortality, daily survival rate, nest success, and nestling weight. In the treated plot, nestling mortality was 81%, 65% of nests were unsuccessful, and mean nestling weight was 1 g less than that in the control plot. In the control plot, nestling mortality was 6% and all nests were successful. A second plot was sprayed in 1989 with an ultra-low-volume formulation of cypermethrin at 3.75 g a.i. per hectare, reducing 90% of the caterpillars but not affecting the availability of other arthropods. Blue tit nestlings were older than one week at the moment of the spraying. In this plot, nestlings from late nests showed a higher mortality and a lower daily survival rate than those in the control plot, the only statistically significant differences in breeding parameters between the plots. We suggest that the negative effects of cypermethrin spraying on breeding success of the blue tit in both treated plots are due to indirect effects (shortage in prey availability) rather than to direct effects (toxicity).

Wild boar population size in the Iberian Peninsula was estimated using hunting bag statistics from Spain and Portugal. Density was estimated assigning the wild boar population size to the "potential resources" or suitable habitats categorized by their importance to provide food and/or shelter to wild boars. Land uses were selected from CORINE, the EU database for land cover, using scientific literature and statistical significance for wild boar presence from published data. The hunting bag was 176245 and 15167 in Spain and Portugal, respectively. The average density was 0.373/km2 (min 0.014-max 2.22) in Spain and 0.13/km2 (min 0.00048-max 1.99) in Portugal, being 0.31/km2 (0.00048- 2.22) over the entire Peninsula. Statistical analysis showed that wild boar presence was significantly (p < 0.05) associated to thirteen of the seventeen CORINE land uses selected. Agro-forestry, moors and heathland land use were not statistically significant but were included in the model due to their biological importance. Suitable habitats and distribution of wild boar were mapped for the Iberian Peninsula. This approach is a preliminary step intended to be useful in environmental management and animal health.