caa a22 4500 463175182 CHVBK 20180406164824.0 cr unu---uuuuu 170326e20070701xx s 000 0 eng 10.1007/s10336-007-0133-5 doi (NATIONALLICENCE)springer-10.1007/s10336-007-0133-5 A long-term large-scale study of the breeding biology of the Spanish imperial eagle ( Aquila adalberti ) [Elektronische Daten] [Antoni Margalida, Luis González, Roberto Sánchez, Javier Oria, Luis Prada, Javier Caldera, Antonio Aranda, José Molina] We present data from a 17-year study of the population biology of a growing population of Spanish imperial eagles Aquila adalberti across most of its breeding range. The objective of this study was to analyse the effects of age, supplemental feeding and rabbit haemorrhagic disease (RHD) on several breeding parameters of this population of eagles. Average clutch size was 2.2 eggs per clutch, and the average incubation time was 41.7days per clutch. Fledging occurred an average of 76.8 days after hatching, the length of the fledgling period was not correlated to clutch size. The annual average percentage of pairs laying eggs was 88%. A significant reduction in the percentage of pairs laying eggs in the period 1992-1994 (from 91 to 81%) coincided with most of the eagles' territories being affected by the rabbit epizootic disease, RHD, which reduced their food supply significantly. Average productivity was 1.23 chicks per monitored territory, average breeding success was 1.40 chicks in a clutch per territory and the average fledging rate was 1.69 chicks per territory with hatching success. The main known causes of breeding failure during incubation were nest collapse and human disturbance. During chick-rearing, total or partial chick losses were mainly caused by siblicide, disease, malnutrition or nest collapse. In 26.2% of the 1372 monitored breeding attempts, at least one of the breeding birds was a subadult (the male in 56.1% of the cases, the female in 15.5% and both sexes in 28.4% of cases). In cases of mixed-aged pairs (n=205), 70.7% were the result of a substitution, and 29.3% were the result of the forming of a new pair. Egg laying took place significantly earlier and breeding success was higher in territories occupied by adults than in those occupied by subadults. Breeding parameters were higher in high-quality (rabbit-rich) territories than in low-quality (rabbit-poor) territories, but only for those territories occupied by adults. The values obtained in the territories occupied by adults were only significantly higher than in those of the subadults in high-quality territories. Age and territory quality thus simultaneously affected reproductive output. Dt. Ornithologen-Gesellschaft e.V., 2007 Breeding biology nationallicence Breeding experience nationallicence Breeding parameters nationallicence Habitat quality nationallicence Spanish imperial eagle nationallicence Supplemental feeding nationallicence Margalida Antoni Bearded Vulture Study and Protection Group, Apdo. 43, El Pont de Suert, 25520, Lleida, Spain aut González Luis Dirección General para la Biodiversidad, Ministerio de Medio Ambiente, C/ Gran Vía San Francisco 4, 28005, Madrid, Spain aut Sánchez Roberto Fundación CBD-Habitat, C/ Nieremberg 8, bajo A, 28002, Madrid, Spain aut Oria Javier Boscaje S.L, C/ San Agustin 22, Segovia, Spain aut Prada Luis Dirección General del Medio Natural, Consejería de Medio Ambiente, C/ Princesa 3, 28008, Madrid, Spain aut Caldera Javier Dirección General de Medio Ambiente, Junta de Extremadura, Apdo. Correos 7, 10181, Sierra de Fuentes Cáceres, Spain aut Aranda Antonio Dirección General del Medio Natural, Junta de Comunidades de Castilla-La Mancha, C/ Pintor Matías Moreno, 4, 45071, Toledo, Spain aut Molina José Dirección General del Medio Natural, Consejería de Medio Ambiente, C/ Rigoberto Cortejoso, 14, 47071, Valladolid, Spain aut Journal of Ornithology Springer-Verlag 148/3(2007-07-01), 309-322 0021-8375 148:3<309 2007 148 10336 https://doi.org/10.1007/s10336-007-0133-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10336-007-0133-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Margalida Antoni Bearded Vulture Study and Protection Group, Apdo. 43, El Pont de Suert, 25520, Lleida, Spain aut NATIONALLICENCE 700 1- González Luis Dirección General para la Biodiversidad, Ministerio de Medio Ambiente, C/ Gran Vía San Francisco 4, 28005, Madrid, Spain aut NATIONALLICENCE 700 1- Sánchez Roberto Fundación CBD-Habitat, C/ Nieremberg 8, bajo A, 28002, Madrid, Spain aut NATIONALLICENCE 700 1- Oria Javier Boscaje S.L, C/ San Agustin 22, Segovia, Spain aut NATIONALLICENCE 700 1- Prada Luis Dirección General del Medio Natural, Consejería de Medio Ambiente, C/ Princesa 3, 28008, Madrid, Spain aut NATIONALLICENCE 700 1- Caldera Javier Dirección General de Medio Ambiente, Junta de Extremadura, Apdo. Correos 7, 10181, Sierra de Fuentes Cáceres, Spain aut NATIONALLICENCE 700 1- Aranda Antonio Dirección General del Medio Natural, Junta de Comunidades de Castilla-La Mancha, C/ Pintor Matías Moreno, 4, 45071, Toledo, Spain aut NATIONALLICENCE 700 1- Molina José Dirección General del Medio Natural, Consejería de Medio Ambiente, C/ Rigoberto Cortejoso, 14, 47071, Valladolid, Spain aut NATIONALLICENCE 773 0- Journal of Ornithology Springer-Verlag 148/3(2007-07-01), 309-322 0021-8375 148:3<309 2007 148 10336 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer