human-associated staphylococcal infection in spanish imperial doñana national park, spain, we compared the prevalence of staphylococcus spp. infections in the spanish imperial eagle (aquila adalberti) in 66 nestlings handled with bare hands and in 46 nestlings handled with gloved hands, 1986 to 1993. we detected staphylococcal infections in 30 (45%) of 66 chicks handled without gloves, and in two (4%) of 46 chicks handled with gloves.19958592386
species variation in osmotic, cryoprotectant, and cooling rate tolerance in poultry, eagle, and peregrine falcon spermatozoa.potential factors influencing spermatozoa survival to cryopreservation and thawing were analyzed across a range of the following avian species: domestic chicken (gallus domesticus), domestic turkey (meleagris gallopavo), golden eagle (aquila chrysaetos), bonelli's eagle (hieraaetus fasciatus), imperial eagle (aquila adalberti), and peregrine falcon (falco peregrinus). studies focused on spermatozoa tolerance to the following: 1) osmotic stress, 2) different extracellular concentrations of the cr ...200010993841
lead shot ingestion in two raptor species from doñana, spain.diurnal raptors inhabiting wetland areas where waterfowl shooting is conducted have many opportunities to ingest lead (pb) shot pellets when feeding on their prey. exposure to pb shot was studied in the spanish imperial eagle (aquila adalberti), an endangered species with a world population of about 150 breeding pairs, and in the red kite (milvus milvus) from doñana (southwest spain). lead exposure was evaluated by the presence of pb shot in the pellets of both species. results obtained by this ...200111161671
blood chemistry, protein electrophoresis, and hematologic values of captive spanish imperial eagles (aquila adalberti).hemograms and plasma chemistry values are presented for six male and six female, adult, clinically normal, captive spanish imperial eagles (aquila adalberti). no value was substantially different from that which might be predicted on the basis of work in other related species. this data should prove useful for the interpretation of laboratory findings in future clinical cases of this endangered species of eagle.200212398298
population genetics after fragmentation: the case of the endangered spanish imperial eagle (aquila adalberti).the highly endangered spanish imperial eagle, aquila adalberti, has suffered from both population decline and fragmentation during the last century. here we describe the current genetic status of the population using an extensive sampling of its current distribution range and both mitochondrial control region sequences and nuclear microsatellite markers. results were evaluated in comparison to those obtained for the eastern imperial eagle, aquila heliaca, its nearest extant relative. mitochondri ...200415245398
lead poisoning in wild birds from southern spain: a comparative study of wetland areas and species affected, and trends over time.we studied lead (pb) shot contamination in sediments from the guadalquivir marshes and six other closed-basin lagoons in southern spain that are of major importance for threatened species of waterbirds. shot densities were relatively low in doñana, ranging from 0 to 25 shot/m(2) in the top 10 cm of sediments. the density at medina lagoon (ramsar site) was 148 shot/m(2), making it the most contaminated wetland known in europe. densities in the other five lagoons ranged from 9 to 59 shot/m(2). we ...200716483652
floater dynamics can explain positive patterns of density-dependent fecundity in animal populations.after some 70 years of debate on density-dependent regulation of animal populations, there is still poor understanding of where spatial and temporal density dependence occurs. clearly defining the portion of the population that shapes density-dependent patterns may help to solve some of the ambiguities that encircle density dependence and its patterns. in fact, individuals of the same species and population can show different dynamics and behaviors depending on their locations (e.g., breeding vs ...200617080366
population fragmentation leads to spatial and temporal genetic structure in the endangered spanish imperial eagle.the fragmentation of a population may have important consequences for population genetic diversity and structure due to the effects of genetic drift and reduced gene flow. we studied the genetic consequences of the fragmentation of the spanish imperial eagle (aquila adalberti) population into small patches through a temporal analysis. thirty-four museum individuals representing the population predating the fragmentation were analysed for a 345-bp segment of the mitochondrial control region and a ...200717257107
west nile virus in the endangered spanish imperial eagle.the spanish imperial eagle (aquila adalberti) is considered to be the most endangered european eagle. the species is an endemic resident in the southwestern iberian peninsula. we used rt-pcr, immunohistochemistry and seroneutralization to test samples from 13 wild and 18 captive eagles. wnv was detected by rt-pcr in tissues and/or oropharyngeal swabs of eight of 10 (80%) imperial eagles analyzed, and both in apparently clinically healthy birds, and in animals that died due to secondary infection ...200818155367
influence of contamination by organochlorine pesticides and polychlorinated biphenyls on the breeding of the spanish imperial eagle (aquila adalberti).we evaluated temporal and regional trends of organochlorine (oc) pesticide (including polychlorinated biphenyl [pcb]) levels in eggs of the spanish imperial eagle (aquila adalberti) collected in spain between 1972 and 2003. levels of p,p'-dichlorodiphenyldichloroethylene (dde) and pcbs varied significantly (p = 0.022) among regions (central, western, and doñana), being higher in doñana than in the central and western populations (dde: 1.64 +/- 5.56, 0.816 +/- 1.70, and 1.1 +/- 2.66 microg/g, res ...200818348639
key role of european rabbits in the conservation of the western mediterranean basin hotspot.the mediterranean basin is a global hotspot of biodiversity. hotspots are said to be experiencing a major loss of habitat, but an added risk could be the decline of some species having a special role in ecological relationships of the system. we reviewed the role of european rabbits (oryctolagus cuniculus) as a keystone species in the iberian peninsula portion of the mediterranean hotspot. rabbits conspicuously alter plant species composition and vegetation structure through grazing and seed dis ...200818680504
avian pox infection in spanish imperial eagles (aquila adalberti).a cutaneous lesion, previously known as "warts", affecting the featherless parts of face and legs has long been recognized in juvenile spanish imperial eagles (aquila adalberti). this paper describes the presentation, microbiological, histopathological, and electron microscopic findings of lesions and diagnosis of poxvirus infection in nine juveniles. lesions consisted of single or multiple nodules with a crust and surrounded by skin swelling. seventy-eight percent of the swabs taken from lesion ...200119184879
solving man-induced large-scale conservation problems: the spanish imperial eagle and power mortality of birds caused by electrocution with poorly-designed pylons and power lines has been reported to be an important mortality factor that could become a major cause of population decline of one of the world rarest raptors, the spanish imperial eagle (aquila adalberti). consequently it has resulted in an increasing awareness of this problem amongst land managers and the public at large, as well as increased research into the distribution of electrocution events and likely miti ...201121399692
when conservation management becomes contraindicated: impact of food supplementation on health of endangered wildlife.understanding the conditions that force the implementation of management actions and their efficiency is crucial for conservation of endangered species. wildlife managers are widely and increasingly using food supplementation for such species because the potentially immediate benefits may translate into rapid conservation improvements. supplementary feeding can also pose risks eventually promoting undesired, unexpected, subtle, or indirect, and often unnoticed, effects that are generally poorly ...201122073636
seropositivity and risk factors associated with toxoplasma gondii infection in wild birds from spain.toxoplasma gondii is a zoonotic intracellular protozoan parasite of worldwide distribution that infects many species of warm-blooded animals, including birds. to date, there is scant information about the seropositivity of t. gondii and the risk factors associated with t. gondii infection in wild bird populations. in the present study, t. gondii infection was evaluated on sera obtained from 1079 wild birds belonging to 56 species (including falconiformes (n = 610), strigiformes (n = 260), ciconi ...201122216311
disease-mediated bottom-up regulation: an emergent virus affects a keystone prey, and alters the dynamics of trophic webs.emergent diseases may alter the structure and functioning of ecosystems by creating new biotic interactions and modifying existing ones, producing cascading processes along trophic webs. recently, a new variant of the rabbit haemorrhagic disease virus (rhdv2 or rhdvb) arguably caused widespread declines in a keystone prey in mediterranean ecosystems - the european rabbit (oryctolagus cuniculus). we quantitatively assess the impact of rhdv2 on natural rabbit populations and in two endangered apex ...201627796353
detection and assessment of electrocution in endangered raptors by infrared thermography.most european birds of prey find themselves in a poor state of conservation, with electrocution as one of the most frequent causes of unnatural death. since early detection of electrocution is difficult, treatment is usually implemented late, which reduces its effectiveness. by considering that electrocution reduces tissue temperature, it may be detectable by thermography, which would allow a more rapid identification. three individuals from three endangered raptor species [spanish imperial eagl ...201323880357
minimising mortality in endangered raptors due to power lines: the importance of spatial aggregation to optimize the application of mitigation measures.electrocution by power lines is one of the main causes of non-natural mortality in birds of prey. in an area in central spain, we surveyed 6304 pylons from 333 power lines to determine electrocution rates, environmental and design factors that may influence electrocution and the efficacy of mitigation measures used to minimise electrocution cases. a total of 952 electrocuted raptors, representing 14 different species, were observed. electrocuted raptors were concentrated in certain areas and the ...201122140549
assessment of lead exposure in spanish imperial eagle (aquila adalberti) from spent ammunition in central spain.the spanish imperial eagle (aquila adalberti) is found only in the iberian peninsula and is considered one of the most threatened birds of prey in europe. here we analyze lead concentrations in bones (n = 84), livers (n = 15), primary feathers (n = 69), secondary feathers (n = 71) and blood feathers (n = 14) of 85 individuals collected between 1997 and 2008 in central spain. three birds (3.6%) had bone lead concentration > 20 μg/g and all livers were within background lead concentration. bone le ...201121327487
small populations and offspring sex-ratio deviations in eagles.stochastic variation of sex ratio has long been appreciated as a potential factor driving small populations to extinction, but it is not the only source of sex-ratio bias in small populations. we examined whether some consequences of sex allocation could affect extinction risk in small populations of size-dimorphic birds such as eagles. we report variations in sex ratio at fledging from a long-term study of a declining population of spanish imperial eagles (aquila adalberti). nestling sex-ratio ...200919627325
positive assortative pairing by plumage colour in spanish imperial eagles.intraspecific variation in plumage may have a functional significance in mate choice. as a result, breeding birds are often paired assortatively with respect to colour. however, whether this within-pair correlation is a result of homotypic preference whereby individuals pick a mate that looks like themselves, or directional preference whereby all individuals have the same phenotypic preference, is often unknown. using data collected between 1989 and 2006, we describe intraspecific variation in t ...200818295983
genetic variability in the iberian imperial eagle (aquila adalberti) demonstrated by rapd analysis.rapd analysis was used to estimate the genetic diversity in an iberian imperial eagle (aquila adalberti) population, one of the most threatened bird species in the world. forty-five of 60 arbitrarily designed primers amplified 614 loci in 25 individual eagles, 59.7% of which were polymorphic. in contrast to the traditional allozyme analysis performed in a previous study, the rapd method has revealed a high level of heterozygosity in this species (h = 0.267+/-0.008). the genetic distances estimat ...200811218090
the karyotype of the iberian imperial eagle (aquila adalberti) analyzed by classical and dna replication banding.we report here for the first time the karyotype of the iberian imperial eagle (aquila adalberti). all eagles examined had a diploid number of 82 chromosomes and a greater number of microchromosomes (12 pairs) than has been found in all other species of the accipitridae family. this karyotypic evidence corroborates the recent separation of a. adalberti from a. heliaca on the basis of molecular data. rb-fpg banding induced a specific banding pattern that allowed us to identify homologous chromosom ...199910343105
age-related changes of plasma alkaline phosphatase and inorganic phosphorus, and late ossification of the cranial roof in the spanish imperial eagle (aquila adalberti c. l. brehm, 1861).plasma alkaline phosphatase and inorganic phosphorus levels were determined for 52 nestling spanish imperial eagles from two wild populations and 22 captive adults and subadults (10 adults and 12 subadults). the exact age was known for all birds. mean alkaline phosphatase and inorganic phosphorus were higher in chicks than in the captive adults and subadults. sex differences were not observed, and nestlings from different populations showed similar values. no significant regression described the ...20139237302
behavioral evidence of hunting and foraging techniques by a top predator suggests the importance of scavenging for preadults.scavenging may be a regular feeding behavior for some facultative raptor species occupying low quality habitats and/or with little experience in hunting techniques. however, its importance has been largely underestimated due to methodological limitations in identifying the real proportion in the diet. here, through direct observations, we assessed the hunting and foraging success of the threatened spanish imperial eagle aquila adalberti determining the influence of age, sex, breeding status, hab ...201728649332
natural expansion versus translocation in a previously human-persecuted bird of prey.many threatened species in europe have been expanding their distributions during recent decades owing to protection measures that overcome historical human activity that has limited their distributions. range expansion has come about via two processes, natural expansion from existing range and reintroductions to new ranges. reintroductions may prove to be a better way to establish populations because individuals are less subject to competitive relationships lowering breeding success than individ ...201728616165
the role of age of first breeding in modeling raptor reintroductions.the present biodiversity crisis has led to an increasing number of reintroduction programs, and this conservation method is likely to be increasingly used in the future, especially in the face of climate change. many fundamental questions in population ecology are focused on the mechanisms through which populations escape extinction.population viability analysis (pva) is the most common procedure for analyzing extinction risk. in the use of pva to model the trajectories of reintroduced populatio ...201930891230
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