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Here we provide the first assessment of the accuracy of lightweight satellite transmitters (,80 g) under actual operating conditions and the performance of the Argos system in southern Europe. To estimate transmitter accuracy we used transmitters equipped with a Global Positioning System (GPS) and compared the location estimates provided by Argos with the estimates provided by the GPS. Using the 68th percentile to define the accuracy of locations estimates, observed accuracy was 4 km for Location Class (LC) 1, 15 km for LC 0, 20 km for LC A, and 59 km for LC B, which is in line with estimates reported by other authors. Yet, the error of the remaining 32% of the data ranged between 4 km and 11 km, 15 km and 217 km, 20 km and 145 km, and 59 km and 493 km, respectively, suggesting that using the 68th percentile to estimate accuracies might give misleading confidence on the accuracy of location estimates. Using the 90th percentile is probably more appropriate. Less than 10% of the locations we obtained corresponded to the more accurate LCs (3, 2, and 1), with Argos failing to provide a position estimate in 45% of the attempts. The low number of high-quality location estimates is likely a consequence of the electromagnetic interference reported for our study area, rather than a defect of the Platform Transmitter Terminals (PTTs), which under good conditions of signal reception seem to be as reliable as heavier ones. The recent advent of lightweight GPS transmitters overrides most of these problems. Yet, whereas the smallest Argos-GPS PTTs weigh 30 g, which restricts their use to animals weighting .1,000 g, conventional PTTs can be as small as 9.5 g, allowing their use with animals weighting 250–300 g. ( JOURNAL OF WILDLIFE MANAGEMENT 71(3):1010– 1015; 2007)

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 set of 10 nuclear microsatellite loci. Data from a previous study on the current population ( N = 79) were re-analysed for this subset of 10 microsatellite markers and results compared to those obtained from the historical sample. Three shared mitochondrial haplotypes were found in both populations, although fluctuations in haplotype frequencies and the occurrence of a fourth haplotype in the historical population resulted in lower current levels of haplotype and nucleotide diversity. However, microsatellite markers revealed undiminished levels of nuclear diversity. No evidence for genetic structure was observed for the historical Spanish imperial eagle population, suggesting that the current pattern of structure is the direct consequence of population fragmentation. Temporal fluctuations in mitochondrial and microsatellite allelic frequencies were found between the historical and the current population as well as for each pairwise comparison between historical and current Centro and historical and current Parque Nacional de Doñana nuclei. Our results indicate an ancestral panmictic situation for the species that management policies should aim to restore. A historical analysis like the one taken here provides the baseline upon which the relative role of recent drift in shaping current genetic patterns in endangered species can be evaluated and this knowledge is used to guide conservation actions.

Aim The Argentine Pampas was extensively and abruptly altered by European colonization. Between 1880 and 1885 the indigenous human inhabitants were completely displaced, and native grasslands were replaced by exotic pasture plants and crops. One of the most important ecological changes in the Pampas landscape, the introduction of tall exotic tree species, has received little attention, and its effect on wildlife has never been assessed. We have made an intensive survey of habitat use of Swainson’s hawk, Buteo swainsoni in its most important non-breeding quarters, the Pampas of Argentina, aiming to characterize the sites used by hawks for communal roosting.

The traditional method of determining gender of Lesser Kestrel (Falco naumanni) nestlings by visual assessment was tested for accuracy by using data from birds banded as nestlings and recaptured as adults. Concordance between gender assignment by different observers, and between visual and molecular gender determination was also evaluated. We tested whether color measurement of rumps and tails could improve gender determination. Based on recaptured kestrels, gender determination by eye had a 9.7% error, and was significantly greater for males than for females. Observers mostly relied on rump and tail color to assign gender to nestlings. Assessment of head, shoulders, tail, and rump patterns did not provide additional information that could improve gender determination in nestlings at the time of banding. Gender assignment based on color measurement on digital photos of rumps and tails did not improve determination by eye, but color measurement from a scanned rump feather approached 100% accuracy. We provide a discriminant function equation based on red, green, and blue brightness values (RCB) of a scanned rump feather and propose this as an efficient and effective method for gender determination in Lesser Kestrel nestlings. © 2005 The Raptor Research Foundation, Inc.

We examined the predatory behavior of Swainson's hawks (Buteo swainsoni Bonaparte, 1838) wintering in the Argentine pampas. Aerial and ground foraging were the main hunting methods employed by hawks in this region. The overall hunting success of hawks preying on insects was 50% and age-related differences in hunting success were not significant. The Swainson's hawks, however, hunted more successfully in the air (65% of prey capture attempts) than on the ground (42%). Aerial hunting while soaring was the most successful hunting method based on the number of prey captured per energy unit. Based on the analysis of prey consumed by hawks during the study period, grasshopper species with poor flight capabilities were available in the air as a consequence of the vertical air motion. With regards to daily activity patterns, the time that a hawk spent using each hunting method was not proportional to the cost ratio associated with each method. Hawks foraged in the air only during midday hours when weather conditions permitted the formation of thermals. Thus, the use of soaring flights and the availability of prey in the air were constrained by the physical environment, and hawks could only exploit airborne food sources during limited periods of the day. © 2005 NRC.

It has been suggested that carotenoid-derived coloration serves as an indicator of parasite levels and (or) the general health of birds. We investigated relationships among spleen size (sometimes considered an indicator of the cellular immune response capacity of birds), carotenoid level, helminth load, and leg and bill coloration of greylag geese, Anser anser (L., 1758), from Doñana National Park (southwest Spain). Nematode abundance was positively related to spleen size and negatively to body condition, but only in males. Coloration of bill and legs was a reliable indicator of cestode but not nematode abundance. Individuals with many cestodes had greater carotenoid stores, suggesting that helminths do not limit carotenoid absorption. Rather, it suggests either that parasitized geese were accumulating more carotenoids to control parasite-induced damage, or that carotenoid-rich diets expose geese to more intermediate hosts of cestodes. Our results support the role of integumentary carotenoid-derived coloration as an indicator of parasitism, but only for particular taxonomic groups. © 2005 NRC Canada.

The white-headed duck is a globally threatened species native to the Palaearctic with a range extending from Spain in the west to the western edge of China in the east. Its populations have become fragmented and undergone major declines in recent decades. To study genetic differences between populations across the range and change in genetic diversity over time, we sequenced a portion of the mitochondrial DNA control region from 67 museum specimens (years 1861—1976) as well as 39 contemporary samples from Spain and seven from Greece (years 1992—2003). In the historical sample, we found a lack of significant genetic structure between populations in different areas. We found evidence that the species experienced a rapid expansion in the past, perhaps from glacial refugia centred around the Mediterranean following the last ice age. In Spain, the population went through a dramatic bottleneck in the 1970s and early 1980s, when only a few dozens individuals remained in the wild. Although population size has since recovered to a few thousand individuals, we found a highly significant loss of mitochondrial haplotype diversity between the historical and contemporary samples. Given ongoing declines in other areas, losses in genetic diversity that may reduce the adaptive potential of white-headed ducks in the future are a continuing concern throughout the geographic range of this species.

Hybridization with a close relative, the North American ruddy duck ( Oxyura jamaicensis ), is a major problem for the conservation of the endangered white-headed duck ( Oxyura leucocephala ). We report the development of 11 microsatellite markers that can facilitate the identification of hybrids as well as the study of the population structure of both species across their distributions. These markers were tested in 63 white-headed ducks and 50 ruddy ducks and show a larger diversity in the latter species.

So far overlooked as a pigment involved in visual communication, the haemoglobin contained in the blood of all birds is responsible for the red flushing colours in bare skin areas of some species. Our aim has been twofold: (1) to study sub-epidermical adaptations for blood circulation in two flushing species: the crested caracara (Polyborus plancus) and the hooded vulture (Necrosyrtes monachus), and (2) to provide the first compilation of avian species with flushing skin. The bare facial skin of both the caracara and the hooded vulture contains a highly vascularised tissue under the epidermis that may be filled with blood and would thus produce red skin colours. In contrast, feathered areas of the head show very few vessels immersed in connective tissue and have no potential for colour changes. Species with flushing colours are few but phylogenetically diverse, as they belong to 12 different avian orders and at least 20 families. The majority are dark-coloured, large-sized species living in hot environments that may have originally evolved highly vascularised skin patches for thermoregulation. Bird behaviour as well as sex and age differences within species suggest that a signalling system for condition or status based on haemoglobin may have been super-imposed to the physiological process of heat dissipation. “Blushing is the most peculiar and the most human of all expressions. Monkeys redden from passion, but it would require an overwhelming amount of evidence to make us believe that any animal could blush” Charles Darwin. 1872. The expression of the emotions in man and animals, Chapter XIII. London, John Murray.

The composition of interstitial waters in Spain’s Don˜ana National Park was assessed 4 years after a major pyrite slurry spill occurred from the Aznalcollar Mine. Metal and nutrient concentrations in pore waters from two of the most important watercourses traversing Don˜ana Park were measured: Guadiamar River (affected by the accident) and Partido Stream (unimpacted by the accident). Concentrations of dissolved constituents in interstitial waters varied according to land use in the two watersheds and to the effects of the mine spill. Levels of dissolved Co, Cu, Mo, Ti, and Zn were higher in pore waters from the Guadiamar River than in the Partido Stream, suggesting that concentrations of trace elements are still influenced by the spill. In contrast, concentrations of dissolved nutrients (NHC4 , NOK2 , NOK3 , POK3 4 ) and some trace metals used in fertilizers (e.g. Al and Cr) were higher in the Partido Stream. Levels of dissolved As, Cs, DOC, Ge, Hg, Rb and V in the interstitial waters were equal in both watercourses. Metal concentrations in interstitial waters of the Guadiamar River floodplain were between 0.3 (As) and 16,000 (Zn) times lower than those previously reported in the river and groundwater a few weeks after the mine spill. Although metals in pore water appear to have reached levels characteristic of the area before the accident, concentrations are 60–150 times higher than those in pore waters from other regions. Metal:Al ratios in Don˜ana’s pore waters suggest a transport of contaminants from the Iberian Pyrite Belt into Don˜ana Park

The red kite (Milvus milvus) occurs in a relatively small area in the southwestern Palearctic region, with population strongholds in Central Europe. Following strong human persecutions at the beginning of the 20th century, populations have receded, particularly in peripheral areas and islands. In order to describe and compare levels of genetic diversity and phylogeographic patterns throughout its entire distribution in Europe, sequence variation of a 357 bps part of the mitochondrial DNA control region was assessed in eight populations and 105 individuals. Overall, results indicate that population declines have aVected red kite mtDNA variation. We found low levels of genetic diversity (values of nucleotide diversity ranging from 0 in Majorca island to 0.0062 in Central Europe), with only 10 distinct haplotypes, separated by low levels of genetic divergence (mean sequence divergenceD0.75%). Highest haplotype and nucleotide diversities match with demographic expectations, and were found in Central European and Central Spanish samples, where present strongholds occur, and lowest values in the declining southern Spanish and insular samples. st estimates indicated moderate gene Xow between populations. Phylogeographic patterns and mismatch distributions analyses suggest central European regions may have been colonized from southern glacial refugia (in the Italian or Iberian peninsulas). InterspeciWc phylogenetic comparisons and divergence date estimates indicated the genetic split between the red kite and its closely related species, the black kite (Milvus migrans), might be relatively recent. The low level of genetic variation found in the red kite mitochondrial control region, compared to the black kite, is likely the result of relatively recent divergence (associated with founder events), successive bottlenecks and small population sizes. As there are several ongoing projects aimed at reinforcing populations in countries such as the United Kingdom, Italy or Spain, our

The strong hunting pressure on the red-legged partridge, Alectoris rufa, warranted its inclusion into the list of species of European conservation concern. During the last decades, restocking plans with farmed specimens have counterbalanced the hunting drawings from wild populations. Our concern was the study of A. rufa in the easternmost part of its range, the central Italy, to gain insights into the effects of this compensation practice on the genetic structure of its populations. Partridges from both a geographically isolated, long-time protected, wild population (Pianosa island, Tuscan Archipelago National Park) and two Tuscan farms (Bieri and Scarlino) were investigated. All the specimens were very similar in outward appearance, looking much like to A. rufa. Ninety-six sequences of both Cytochrome b and D-loop Control Region of mitochondrial DNA (mtDNA) were analysed to get evidence of ancestry at the population level, whereas, the Random Amplified Polymorphic DNA (RAPD) technique was employed to get fingerprinting at the individual level. Pianosa and Bieri populations showed both the A. rufa and Alectoris chukar mtDNA lineages, whereas the Scarlino one only the A. rufa-mtDNA line. However, a spread overall pattern of A. rufa · A. chukar hybridisation among specimens, whatever their mtDNA lineage could result to be, was disclosed by means of RAPD species-specific markers. This is the first genetically documented record of the A. rufa · A. chukar hybrids. The occurrence of the pure, native A. rufa genome in the easternmost part of the species geographical range may be guessed to be virtual. .

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. Mitochondrial haplotype diversity was lower in the Spanish than in the Eastern species whereas microsatellite allelic richness and expected heterozygosity did not differ. Both allelic richness and expected heterozygosity were lower in the small Parque Nacional de Doñana breeding nucleus compared to the remaining nuclei. A signal for a recent genetic bottleneck was not detected in the current Spanish imperial eagle population. We obtained low but significant pairwise F ST values that were congruent with a model of isolation by distance. F ST and exact tests showed differentiation among the peripheral and small Parque Nacional de Doñana population and the remaining breeding subgroups. The centrally located Montes de Toledo population did not differ from the surrounding Centro, Extremadura and Sierra Morena populations whereas the latter were significantly differentiated. On the other hand, a Bayesian approach identified two groups, Parque Nacional de Doñana and the rest of breeding nuclei. Recent migration rates into and from Parque Nacional de Doñana and the rest of breeding nuclei were detected by assignment methods and estimated as 2.4 and 5.7 individuals per generation, respectively, by a Bayesian approach. We discuss how management strategies should aim at the maintenance of current genetic variability levels and the avoidance of inbreeding depression through the connection of the different nuclei.

Despite recovery plans, the Spanish Imperial Eagle (Aquila adalberti) and the Iberian lynx (Lynx pardinus) are in danger of extinction. These two flagship species tend to occur in pristine Mediterranean forests, and both prey preferentially on the rabbit (Oryctologus cuniculus). Spanish lynxes and eagles have sister species in continental Europe, the Eurasian lynx ( Lynx europaeus) and the Eastern Imperial Eagle (A. heliaca), respectively. Recent genetic evidence indicates that these two pairs of species started to diverge from their ancestor species slightly less than 1 million years ago, when the longest-lasting Pleistocene glaciations covered Europe. We hypothesize that the Iberian lynx and the Spanish Imperial Eagle emerged as separate species in the Pleistocene refugia of southern Spain, where they hunted yet another locally evolved species, the rabbit, on which they have become dependent for survival. Two large predators that emerged at the same time may go extinct simultaneously because of their inability to shift to alternative prey. Many other relict species, including numerous species from oceanic islands, have naturally small populations because of evolutionary constraints and are permanently threatened with extinction. Recovery plans aimed at putting these species out of danger are unrealistic, as their populations are and have been chronically scarce. We suggest that what these species need are maintenance plans designed to buffer population declines due to either stochastic or human-induced events. A metaphor for this would be “emergency care units” for conservation, A pesar de planes de recuperaci´on, el ´ Aguila Imperial Espa˜nola (Aquila adalberti) y el lince Ib´erico (Lynx pardinus) se encuentran en peligro de extinci´on. Estas dos especies bandera tienden a ocurrir en bosques mediterr´aneos pr´ıstinos y preferentemente depredan al conejo (Oryctologus cuniculus). Los linces y ´aguilas espa˜noles tienen especies hermanas en Europa continental, el lince Euroasi´atico (Lynx europaeus) y el ´aguila Imperial Oriental (A. heliaca), respectivamente. Evidencia gen´etica reciente indica que estos dos pares de especies comenzaron a divergir de su especie ancestral hace poco menos de 1 mill´on de a˜nos, cuando las glaciaciones m´as prolongadas del Pleistoceno cubr´ıan Europa. Nuestra hip´otesis es que el lince ib´erico y el ´aguila imperial espa˜nola emergieron como especies separadas en refugios pleistocenos del sur de Espa˜na, donde cazaban a otra especie que evolucion´o localmente, el conejo, de la que se han vuelto dependientes para sobrevivir. Dos depredadores grandes que emergieron al mismo tiempo pueden extinguirse simult´aneamente debido a su incapacidad de cambiar a presas alternativas. Muchas otras especies relicto, incluyendo numerosas especies de islas oce´anicas, tienen poblaciones naturalmente peque˜nas debido a restricciones evolutivas y est´an permanentemente amenazadas de extinci´on. Los planes de recuperaci´on enfocados en poner a estas especies fuera de riesgo, son calistas, ya que las poblaciones son y han sido cr´onicamente escasas. Sugerimos que lo que necesitan estas especies son planes de conservaci´on dise˜nados para amortiguar declives poblacionales debidos a eventos estoc´asticos o inducidos por humanos. Una met´afora para esto ser´ıa “unidades de cuidado de emergencia” para la conservaci´on.

We assessed the nutritional condition and established reference values for serum chemistry parameters in a long distance migrant bird of prey, the Swainson’s Hawk (Buteo swainsoni), wintering in central Argentina. We analyzed serum concentration of urea, uric acid, cholesterol, and triglycerides and assessed age and sex related differences in these parameters. A body condition index was obtained from the resultant residuals of the regression of body mass and a morphometric measure. No statistical differences were observed among sex and age groups for urea, uric acid and triglyceride serum concentration. However, cholesterol concentration differed among male and female hawks, which could be related to the gain of body mass in wintering grounds at differential rates. The mean values of the four parameters were in the range of those recorded in the Common Buzzard (Buteo buteo), indicating good nutritional condition of the population we studied. Forearm length was the morphometric variable that better correlated with body mass. The resultant body condition index was only correlated with triglyceride concentration, suggesting that this index could be valuable in future work dealing with the assessment of body fat storage in wintering and breeding hawks, as well as in stopover points on the migratory route.

Non-invasive sampling is a useful tool for genetic analyses of endangered and1or elusive species, but it is often inapplicable due to the low quality and quantity of the DNA obtained. In this study we show that the blood clot located in the superior umbilicus of the feather shaft is a better source of DNA than the previously used tip samples from moulted feathers. We found that feather clots from museum specimens provided results nearly as good as footpad and better than those from the more commonly used museum skin snips. Feather clots proved to be a good source of DNA for genetic analysis that will significantly facilitate genetic monitoring of wild bird populations.

The Egyptian vulture (Neophron percnopterus) is a species in decline throughout Europe, with the largest remain- ing breeding populations found in northern Spain. Iberian Peninsula populations of this species (about 1000 pairs) migrate to Africa in winter, while small populations in both the Canary and Balearic Islands (less than 40 pairs in each case) are apparently sedentary. We found that Egyptian vultures from both of these island groups were significantly differentiated from Iberian Peninsula populations (RST = 0.065–0.129, p = 0.000–0.007), using nine microsatellite loci isolated in a related species, the bearded vulture. The greatest degree of genetic differentiation was observed between the two island groups (RST = 0.279, p = 0.000). These island populations were more distinct from mainland groups than was a small sample of a well-defined separate subspecies from India (N. p. ginginianus; RST = 0.083–0.091, p = 0.023–0.024). This implies that these two island populations have been isolated from peninsular populations for many generations, despite the long-distance migration capabilities of the species. In constrast, populations within the Peninsula were not differentiated from one another at these microsatellite loci (RST = −0.004–0.007, p = 0.442–0.675). Introductions of Egyptian vultures from the larger northern breeding groups might therefore be appropriate in southern Spain, if necessary, but mainland birds should not be introduced to the islands if the genetic distinctiveness of these groups is to be preserved. Independent conservation plans are urgently required to protect these two island populations from extinction.

We have hypothesized (Negro et al. 1999) that bearded vultures, Gypaetus barbatus, deliberately stain their plumage with iron oxides to signal dominance status. The conceptual frame to which we ascribe our hypothesis is the handicap principle (Zahavi & Zahavi 1997). For a signal to convey reliable information, and thus to evolve, it has to be costly (Zahavi 1975), and we proposed that the associated cost of the red colour signal for bearded vultures is that adequate ferruginous springs are a limited resource.

On the basis of four study skins from museum collections and 37 live birds from the island of Fuerteventura, we describe a new subspecies of the Egyptian Vulture (Neophron percnopterus majorensis) from the Canary archipelago. Canarian Egyptian Vultures are significantly larger than Western European and North African individuals. In addition, some genetic differentiation may exist; analyses of the mitochondrial DNA control region revealed that there are haplotypes exclusive to the Canary Islands. The current population of Egyptian Vultures in the Canary Islands is 25-30 breeding pairs restricted to the islands of Fuerteventura and Lanzarote, and this subspecies is therefore endangered. © 2002 The Raptor Research Foundation, Inc.

Here we describe the development of 18 polymorphic microsatellite markers for the endangered Spanish imperial eagle ( Aquila adalberti ). Microsatellites were tested in five other raptor species. These markers were revealed as good molecular tools for genetic population studies, individual identification and parentage assessment in Spanish imperial eagle and closely related species.

The salient feature of the fatty acid profile of kestrel eggs collected in the wild was the very high proportion of arachidonic acid (15.2% 0.7% of fatty acid mass, np5) in the phospholipid fraction of the yolk. Kestrels in captivity fed on dayold chickens produced eggs that differed from those of the wild birds in a number of compositional features: the proportion of linoleic acid was increased in all the lipid fractions; the proportion of arachidonic acid was increased in yolk phospholipid and cholesteryl ester; the proportion of a-linolenic acid was decreased in all lipid classes, and that of docosahexaenoic acid was decreased in phospholipid and cholesteryl ester. Partridge eggs from the wild contained linoleic acid as the main polyunsaturate of all the yolk lipid fractions. Captive partridges maintained on a formulated diet very rich in linoleic acid produced eggs with increased levels of linoleic, arachidonic, and n-6 docosapentaenoic acids in the phospholipid fraction; reduced proportions of a-linolenic acid were observed in all lipid classes, and the proportion of docosahexaenoic acid was markedly reduced in the phospholipid fraction. Thus, captive breeding of both the kestrel and the partridge increases the n-6/n-3 polyunsaturate ratio of the yolk lipids.