Murgui E.,Grupo Para El Estudio de Las Aves. |
MacIas A.,Technical University of Madrid
Bird Study | Year: 2010
Capsule The population of House Sparrow Passer domesticus has experienced a sharp decline in the municipality of Valencia. Aims To investigate the population trends of House Sparrows. Methods Between September 1998 and December 2008, House Sparrows were censused monthly in 22 urban parks covering a total of 118 ha. Additionally, birds in the wider urban landscape were censused in 24 plots of about 50 ha during the winter and spring of years 1998, 2003 and 2007. Results The House Sparrow population experienced a significant decline of about 70% over 10 years in urban parks, with monthly peak values decreasing from about 2000 birds in 1998 to about 500 in 2008. Between 1998 and 2007, a significant decline was detected in the urban landscape mostly during the winter. Conclusions Urban parks are a main feeding habitat for House Sparrows, and habitat structure of urban parks has remained similar throughout these years. Therefore, the decreasing number of sparrows recorded in parks probably reflects an overall population decline of the species in Valencia. This decline has coincided with high-intensity urban development i.e. an increase in the building density and a reduction in the amount of wastelands and other feeding habitats. Thus, shortage of nest-sites did not seem to be a limiting factor for the population, but a reduction of food availability may be partially responsible for the observed patterns. © 2010 British Trust for Ornithology.
Murgui E.,Grupo para el Estudio de las Aves
Bird Conservation International | Year: 2014
Summary The parany is a device used in Comunidad Valenciana (Spain) for trapping birds by the use of limed sticks. Between 1988 and 2001 successive Comunidad Valenciana governments authorised the legal trapping of thrushes Turdus spp. in 5,000 parany each year. Approximately 1.5 million thrushes (mostly Song Thrush Turdus philomelos and Redwing T. iliacus) along with half a million birds of many protected species (including raptors) were trapped annually. Authorisation ceased in 2001 but illegal trapping still occurs, using at least 2,000 parany. Comunidad Valenciana governments have explicitly supported bird trapping on both legal and technical grounds claiming that only small numbers of thrushes are caught and that other species are unaffected, thus complying with the EU Birds Directive. Such assertions have never been proven, and regional, national and international courts have declared that the parany contravenes nature protection laws. Comunidad Valenciana governments have deliberately overlooked such judgements. It is concluded that eradication of parany through law enforcement and educational schemes would be the best option. Nevertheless, according to the EU Birds Directive, controlled bird trapping would be feasible, and the requisites for such a strategy are discussed. The main obstacle to both eradication and strictly controlled use of parany is the lack of political will by Comunidad Valenciana governments. © BirdLife International 2013.
Murgui E.,Grupo para el Estudio de las Aves
Ecography | Year: 2010
Although nested species subset patterns and mechanisms promoting them have constituted the focus of a considerable research effort, little attention has been paid to the role of seasonality in generating or moderating these patterns. I conducted monthly censuses of 130 urban parks in the city of Valencia throughout an annual cycle to assess whether seasonality influenced nested patterns of bird species assemblages. Specifically I tested the hypothesis that an increase in the movement of birds among parks outside of the breeding season, may reduce nestedness of resident birds. Results obtained in this study showed that assemblages of resident bird species were nested during the breeding season but not outside it, thus giving some support to the hypothesis. However, a reduction in nestedness outside the breeding season was not explained by an increase in the occupancy of parks but with an increase in the number of absences from parks that had been inhabited during the breeding season, most likely due to the use of habitats outside parks by some species (finches mainly). Results suggest the importance of both selective extinction and colonization processes in contributing to the degree of nestedness during the breeding season. However, environmental stress in the form of human disturbance apparently had little effect on the distributions of individual species. Habitat nestedness did not appear to be a factor as parks of all sizes were similar in number and type of habitats. An assessment of seasonality in other landscapes is needed to further understand its general effects on nestedness. © 2010 The Authors.
Murgui E.,Grupo Para el Estudio de Las Aves
Ardeola | Year: 2010
Relatively little research has been reported on bird fauna associated with European traditional irrigated systems. This paper examines the seasonal bird use of crop types in one of such agro-ecosystem the Huerta of Valencia (Spain). Three hundred and seventy nine cultivated fields were censused on a monthly basis from June 2002 to May 2003, and the patterns of bird species richness and crop type selection were examined through Generalized Linear Models (GLM) and resource selection functions. Sixty-nine species were recorded, reaching maximum values of species richness and bird abundance during winter. The bird assemblage was much skewed with six species accounting for 70 % of the birds recorded. Results indicated that high species richness was associated with fallow fields and orange groves with weeds, but this result was partially dependent on seasons and management. Conversely, most row crops were hardly used by birds. Although no data on bird populations inhabiting the Huerta before agricultural intensification processes exists, data suggests an impoverishment of bird fauna in the last decades mainly through the removal of non-crop habitats. However, the main threat to bird fauna is currently land transformation of the Huerta for urban or industrial purposes. Conservation of this agroecosystem and of its rich cultural heritage will need agri-environmental programs along with proper landscape planning policies.