Seasonal patterns of bird crop use in traditional irrigated land (the Huerta of Valencia, Spain)

Full article

Published:

Volume 57(1), junio 2010. Pages 87-102

Language:

English

Keywords:

agricultural intensification, cropland, habitat selection, Huerta, landscape planning, orange groves and Valencia

Abstract:

 

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.