Alectoris Rufa Research Articles

Conserving the European Bonelli's eagle in spatiotemporal domain: Lesson from its feeding pattern

Bonelli's eagle (Hieraaetus fasciatus), a threatened species in Western Europe, has suffered a critical and severe decline in last two decades. In this article, a qualitative analysis of an ecoepidemiological model which consists of two prey and a predator is carried out. We proposed and designed a spatiotemporal model to predict the distribution of a territorial predator, Bonelli's eagle and its two main prey species (rabbit and red-legged partridge). Bounded positive solution, feasibility of the equilibria, and their stability analysis are determined for the nonspatial counterpart of the system. Criteria for diffusion-driven instability caused by local random movements of rabbits, partridges, and Bonelli's eagle are obtained. Possible implications of the result for Bonelli's eagle conservation are discussed. We show that the inclusion of second prey in the system can drastically change the dynamics from the single prey case. We also found that the presence of a second prey is beneficial for the conservation of the threatened Bonelli's eagle population in Europe. Results obtained from theoretical analysis of the nonspatial model agree very well with the numerical simulation results. Lastly, via numerical simulation, we illustrate the effect of diffusion of the dynamical system in the spatial/spatiotemporal domain by different pattern formations.

How many gamebirds are released in the UK each year?

Large numbers of gamebirds (pheasants Phasianus colchicus, red-legged partridges Alectoris rufa and mallard Anus platyrhynchos) are released annually in the UK to support recreational shooting. It is important to know how many of these birds are being released because their release and management has ecological effects on the wildlife and habitats of the UK. There is little regulation governing their release, and consequently, an accurate figure for the numbers being released is unknown. I took 12 different approaches, totalling 4329 estimates of the numbers of birds being released annually, based on a series of datasets that described numbers of birds being held for breeding, rearing or release, being released, managed or shot on game shoots, being shot by individual guns or being recorded during breeding bird surveys. These 12 approaches produced estimates ranging from 14.7 to 106.1 million with a mean of 43.2 million (95% CI 29.0–57.3 million). This suggests that 31.5 million pheasants (range 29.8–33.7 million), 9.1 million red-legged partridges (range 5.6–12.5 million) and 2.6 million mallard (range 0.9–6.0 million) are released annually in the UK. These figures differ substantially from both official records of gamebirds and previous published estimates, and I discuss why such differences may occur. I set these figures in the context of the number and behaviour of shoots operating in the UK. Improved estimates of numbers of gamebird being released are critical if we are to better understand the ecological effects occurring in areas where they are released and managed.

First Data on Gastrointestinal Parasitic Infection in the Red-Legged Partridge (Alectoris rufa) in Italy

The Red-legged partridge (Alectoris rufa) is a Mediterranean Galliformes, recently classified as Near Threatened by the International Union for the Conservation of Nature, due to the constant and significant decline of its global population. While the gastrointestinal parasites of the species are well studied in some part of its range (Iberian peninsula), limited information is available for the Italian populations, that represent the eastern limit of the species range. This study was conducted to fill this gap of knowledge, determining the composition, richness, prevalence, intensity and abundance of A. rufa gastrointestinal parasite community in two populations in Italy. During the autumn seasons 2008–2009 and 2009–2010, necropsies were conducted on 18 Red-legged partridge from the southern part of Alessandria province (Piedmont, northwestern Italy) and 34 from the Parma province (Emilia Romagna, northern Italy). All the animals were examined for the presence of gastrointestinal parasites. Additionally, 229 fecal samples were collected from live animals in Alessandria province. Prevalence, abundance and intensity of infection were calculated for each parasite species, except for coccidia for which only the prevalence was determined. The following parasites were observed: Heterakis gallinarum, Ascaridia spp., Ascaridia columbae, Raillietina spp., Eimeria spp. The highest parasite prevalence was found in Alessandria province for Eimeria sp., infecting almost half of the sampled animals (P: 45%, CI95%: 39–51). Eimeria sp. was also the most prevalent parasite in Parma province but with much lower prevalence (P: 19%, CI95%: 5–32). Intestinal helminths prevalence ranged from 3% (CI95%: 0–9) for A. columbae and Raillietina spp. (Parma Province) to 9% for H. gallinarum in both Parma (CI95%: 0–19), and Alessandria province (CI95%: 0–22). To our knowledge, this is the first study providing information on the gastrointestinal parasites of the Red-legged partridge in Italy. Ascaridia columbae, a parasite typical of the domestic pigeon, was reported for the first time in A. rufa. The epidemiological descriptors reported herein could serve as a basis for future studies, allowing for epidemiological comparison across countries, locations, and time periods.

Pathogenesis of Two Western Mediterranean West Nile Virus Lineage 1 Isolates in Experimentally Infected Red-Legged Partridges (Alectoris rufa).

West Nile virus (WNV) is the most widespread flavivirus in the world with a wide vertebrate host range. Its geographic expansion and activity continue to increase with important human and equine outbreaks and local bird mortality. In a previous experiment, we demonstrated the susceptibility of 7-week-old red-legged partridges (Alectoris rufa) to Mediterranean WNV isolates Morocco/2003 and Spain/2007, which varied in virulence for this gallinaceous species. Here we study the pathogenesis of the infection with these two strains to explain the different course of infection and mortality. Day six post-inoculation was critical in the course of infection, with the highest viral load in tissues, the most widespread virus antigen, and more severe lesions. The most affected organs were the heart, liver, and spleen. Comparing infections with Morocco/2003 and Spain/2007, differences were observed in the viral load, virus antigen distribution, and lesion nature and severity. A more acute and marked inflammatory reaction (characterized by participation of microglia and CD3+ T cells) as well as neuronal necrosis in the brain were observed in partridges infected with Morocco/2003 as compared to those infected with Spain/2007. This suggests a higher neurovirulence of Morocco/2003, probably related to one or more specific molecular determinants of virulence different from Spain/2007.

Vineyard modernization drives changes in bird and mammal occurrence in vineyard plots in dry farmland

The fast intensification of agriculture affects many systems. In recent decades, traditional vineyards have been rapidly converted to trellis vineyards in Spain (the country with the largest vineyard surface worldwide) in an attempt to reduce harvesting costs and increase vine productivity. The implications of this modernization of vineyards on farmland biodiversity are still largely unknown. We studied 52 vineyards (26 traditional and 26 trellis) from June to September in south-western Spain, aiming to describe the effect of the modernization of goblet-shape traditional vineyards on vine structure and their management, as well as its effect on species' occurrence in vineyard plots. We applied hierarchical occurrence models to assess the occurrence probability of 10 bird species and two mammal species in traditional and trellis vineyard plots. Vineyard modernization involved taller vines (connected by metallic guide wires and poles by rows), greater distance between vine rows, bigger plot sizes, the systematic implementation of irrigation, and an application of fertilizers through the watering system (fertirrigation) in a third of studied vineyards. Other agrochemical treatments seemed to be equally used in both vineyard types. Due to the use of herbicides and frequent tilling, both types of vineyards showed low natural vegetation groundcover. Vineyard modernization had clear effects on fauna biodiversity in vineyard plots, with a higher occurrence in trellis vineyards of some species (rufous-tailed scrub-robin, European goldfinch, red-legged partridge, and house sparrow) and a higher occurrence of other species (European rabbit and European greenfinch) in traditional ones. Thus, vineyard modernization can drive a change in the community of birds and mammals that inhabit them. In addition, vineyard use by some species (particularly ground-dwelling ones) was strongly determined by the presence of arable land adjacent to the vineyard. These species may therefore use vineyards during summer because they provide water and/or better cover than harvested crops. Animals attracted to vineyards for water could be exposed to toxic doses of nitrates that are routinely applied through the watering system in a third of these. To maximize benefits for biodiversity, it would be advisable to manage modernization schemes in order to maintain landscape heterogeneity, with vineyards of both types combined with other agricultural systems, as well as higher proportions of natural vegetation surface cover.

Genome-wide markers redeem the lost identity of a heavily managed gamebird.

Heavily managed wildlife may suffer from genetic homogenization and reshuffling of locally adapted genotypes with non-native ones. This phenomenon often affects natural populations by reducing their evolutionary potential and speeding up the ongoing biodiversity crisis. For decades, the red-legged partridge (Alectoris rufa), an intensively managed gamebird of conservation concern and considerable socio-economic importance, has been subjected to extensive releases of farm-reared hybrids with the chukar partridge (Alectoris chukar) and translocations irrespective of subspecific affinity. These practices have led to serious concerns that the genetic integrity and biogeographic structure of most red-legged partridge populations are irreversibly affected, as suggested by previous studies based on few genetic markers. Using over 168 000 genome-wide loci and a sampling across the entire A. rufa range, we detected unexpectedly limited and spatially uneven chukar introgression as well as significant intraspecific structure. We demonstrate that species widely feared to have irretrievably lost their genetic identity are likely to be much less affected by unsuitable management practices than previously assumed. Our results spell the need for a radical re-think on animal conservation, possibly restoring native status to populations long treated as compromised. Our study exemplifies how the application of innovative conservation-genomic methods is key to solving wildlife management problems dealing with introgressive hybridization worldwide.

A stereological study of the renal and adrenal glandular structure of red-legged partridge (Alectoris chukar).

Partridge is a major bird species that has recently gained an increasing importance as an alternative food source and a game animal in hunting tourism. Herein, we aimed to examine the histological structure and stereological properties of the renal and adrenal glands of red-legged partridge. Seven healthy adult red-legged partridges (Alectoris chukar) of both genders were used in this study. The Alectoris chukars were perfused with the intracardiac method and were kept in 10% formaldehyde for 72 h for optimal fixation. The tissues were embedded in paraffin after routine light microscopic processes. Then, 5-μm thick sections were taken, which were stained with haematoxylin and eosin, photographed, and examined in light microscope. Modified Cavalieri principle was used for volume calculation as stereological analysis. Total tissue volume ratios were calculated with the help of a point grid provided by the Shtereom 1.5 packaged programme. Mann Whitney-U test was used for inter-group comparisons. The significance level was set at 5% SPSS (ver: 13) statistical software was used for all statistical analyses. Renal histological structure was found to resemble those of other bird species and contained a mixed type (mammalian, reptilian) glomerular structure. It was also found that the adrenal histology was not in the form of separate layers but composed of cell groups with different properties. Stereological renal volume assessment revealed statistically similar right and left renal size (p > 0.05). In adrenal gland volume assessment, the right and left adrenal volumes were also statistically similar (p > 0.05). The obtained data in the present study is thought to contribute to the understanding of the stereological, morphological and histological structure of the red-legged partridge (Alectoris chukar) kidney and adrenal gland.

Contribution of non-native galliforms to annual variation in biomass of British birds

Millions of individuals of two species of non-native galliform birds, the Common Pheasant (Phasianus colchicus) and Red-legged Partridge (Alectoris rufa) are released into the British countryside annually in late summer, supplementing established breeding populations of these two species. The biomass of birds involved in these releases has been compared to the British breeding bird biomass. However, the validity of this comparison is compromised because the biomass of wild birds varies across the year due to reproduction, mortality and migration. How the biomass of Common Pheasants and Red-legged Partridges compares to that of other British bird species in late summer, or across the whole year, is currently unknown. Here, we produce estimates of how British bird biomass varies across the year, to assess the contribution of the two non-native galliforms to this variation. We show that overall British bird biomass is probably lowest around the start of the breeding season in April, and peaks in late summer and autumn. We estimate that around a quarter of British bird biomass annually is contributed by Common Pheasants and Red-legged Partridges, and that at their peak in August these two species represent about half of all wild bird biomass in Britain.

The end of primary moult as an indicator of global warming effects in the Red-legged Partridge Alectoris rufa, a medium sized, sedentary species

Global warming affects ecosystem services, communities and populations, influencing the physiology, behaviour or environment of living beings, and hence impacts its survival or breeding. Identifying species susceptibility to warming is relevant in assessing risks to animal populations and ecological processes. The progressive increase in ambient temperature as a result of global warming might have an effect on the timing of primary moult. This could affect a bird’s annual cycle, influencing reproductive success and population dynamics.We describe a method to examine the potential effects of global warming on the primary moult process in a sedentary population of Red-legged Partridges (Alectoris rufa). We organised the factors that might influence the timing of moult end into a network and distinguished between environmental and intrinsic factors. We sorted the factors according to their contribution to quantitative moult models and constructed a diagrammatic scheme showing their interactions and effect on the end of primary moult over the annual cycle.In Red-legged Partridges, the timing of the end of moult varies according to age-sex class. We found no timing differences by age, but found significant timing differences by adult sex. More females overlap their moult with juveniles than males because female parental effort is higher, more females incubate and brood chicks. The timing of the end of moult varies by year due to conspecific interactions that change according to influences of the weather, habitat, and social and flock conditions. Parent birds synchronize their primary moult with the chick's growth, degree of cover and food resources. From the time of hatching to the following year, the date (day-length), social factors (conspecific interactions), and weather (resources) affect the timing of moult and the birds’ annual cycle.Global warming affects the timing of the end of moult and that of the annual cycle. If the extent of the breeding period is shortened, there could be a negative effect on population outcomes. Middle size prey species are key in trophic chains. Our results suggest that the timing of the end of moult could be used as a proxy measure of warming impacts on wildlife and ecosystems and also as a tool for the management of game birds.

Birds feeding on tebuconazole treated seeds have reduced breeding output.

Drilled seeds are an important food resource for many farmland birds but may pose a serious risk when treated with pesticides. Most compounds currently used as seed treatment in the EU have low acute toxicity but may still affect birds in a sub-chronic or chronic way, especially considering that the sowing season lasts several weeks or months, resulting in a long exposure period for birds. Tebuconazole is a triazole fungicide widely used in agriculture but its toxicity to birds remains largely unknown. Our aim was to test if a realistic scenario of exposure to tebuconazole treated seeds affected the survival and subsequent reproduction of the red-legged partridge (Alectoris rufa). We fed captive partridges with wheat seeds treated with 0%, 20% or 100% of tebuconazole application rate during 25 days in late winter (i.e. tebuconazole dietary doses were approximately 0.2 and 1.1mg/kgbw/day). We studied treatment effects on the physiology (i.e. body weight, biochemistry, immunology, oxidative stress, coloration) and reproduction of partridges. Exposed birds did not reduce food consumption but presented reduced plasmatic concentrations of lipids (triglycerides at both exposure doses, cholesterol at high dose) and proteins (high dose). The coloration of the eye ring was also reduced in the low dose group. Exposure ended 60 days before the first egg was laid, but still affected reproductive output: hatching rate was reduced by 23% and brood size was 1.5 times smaller in the high dose group compared with controls. No significant reproductive effects were found in the low dose group. Our results point to the need to study the potential endocrine disruption mechanism of this fungicide with lagged effects on reproduction. Risk assessments for tebuconazole use as seed treatment should be revised in light of these reported effects on bird reproduction.

An open platform system based on SNP type genetic markers for discrimination between Alectoris rufa and Alectoris chukar

The red-legged partridge (Alectoris rufa) is one of the most emblematic game species in Southern Europe. For the conservation of its natural populations against hybridization with chukar partridges (Alectoris chukar) a public and agreed control system able to detect genetic introgression between the two species should be established. As the already available method has not been implemented yet, this paper presents an improvement of the genetic analysis technique by using an open platform system to optimize the diagnostic procedure. Here we present the results obtained from the design of an Open Array™ platform with the available SNPs with proved diagnosis capacity between the two species of interest. By this procedure we genotyped 380 partridge samples, both from farms and field populations, which resulted in an overall percentage of genotyping performed with success of 99.64%. The Open Array genotyping plates showed high performance, specificity and an easy reproducibility compared to conventional techniques of genotyping.

Pathology of Trombiculosis caused by Neoschoengastia simonovichi in Wild Red-Legged Partridges (Alectoris rufa)

Lesions caused by trombiculid mite larvae ('chiggers') in birds have been inadequately described. A juvenile red-legged partridge (Alectoris rufa) presented with multifocal, crater-like lesions of necrotizing dermatitis, which often contained multiple orange mites. Microscopically, there was a nodular necrotizing and pyogranulomatous dermatitis with occasional intralesional arthropods. Histologically, the mites were readily identified by the presence of stylostomes within the necrotic areas. Morphological and morphometrical studies on isolated mites identified them as Neoschoengastia (Hypogastia) simonovichi. This is the first report of N. simonovichi as an aetiological agent of severe trombiculosis in wild birds in Western Europe. Infestation with this parasite requires further study to understand its role in animal and human trombiculosis and its potential role as a vector of infectious, including zoonotic, agents.

Red-legged partridge Alectoris rufa productivity in relation to weather, land use, and releases of farm-reared birds

Productivity (offspring production) is a key demographic parameter influencing population dynamics, particularly in r-strategy species, and thus critical for implementing well-based management of populations. Accordingly, the study of factors influencing productivity is useful to develop management strategies in species of conservation concern or subject to exploitation. We studied productivity (covey size and young/adult ratio) of red-legged partridges (Alectoris rufa) in Spain through a large-scale sampling in Andalucia and Castilla-La Mancha, two large areas in central-southern Spain, the core of the distribution of the species. We evaluated potential environmental factors related with productivity that have been considered important in previous local studies (weather, land use, and intensity of releases of farm-reared partridges), using a dataset of 15,357 observations of partridges over three breeding seasons (2010, 2011, and 2012). Average productivity at the end of July was 3 young/adult, indicating 50% chick mortality between hatching and fledging and high breeding failure. We found marked effects of weather, year, and land use on partridge productivity, confirming some previous results at local scale and supporting widespread and simultaneous effects of these factors. We also detected a large-scale negative relationship with farm-bred partridge release intensities, with lower young/adult ratios in areas with high release intensity. This suggests that partridge releases may be contributing to the decline of wild populations. Our results support that correcting the effects of agricultural intensification is the main key to the long-term conservation of the species and suggest that, in dry spring years (leading to low average productivity), many populations could be exposed to overhunting. These results stress the importance of both small- and large-scale adjustments of hunting pressure to partridge productivity, in order to preserve wild populations. Poor hunting bags in “bad” years, along with the increasing demand in the hunting market, may have stimulated the widespread use of releases, further reducing productivity and leading to the current compromised conservation status of wild populations. We discuss some potential solutions to this conflicting situation from the socioeconomic and environmental points of view.

Egg Overspray with Herbicides and Fungicides Reduces Survival of Red-Legged Partridge Chicks.

Within the environmental risk assessment conducted for pesticide registration in the European Union (EU), avian reproductive toxicity is characterized after exposing adults. However, eggs of ground-nesting species can be exposed when pesticide applications occur during laying or incubation. We simulated environmentally realistic exposure of red-legged partridge (Alectoris rufa) eggs to an herbicide (2,4-D) and a fungicide (tebuconazole) applied to winter cereal crops during the breeding season of most farmland birds. We analyzed the effects on hatching success, offspring survival, and physiology. Exposure by overspray led to greater pesticide accumulation in the eggshell or content than exposure through contact with treated soil (3.1-13.7 times higher, depending on the pesticide and target sample). Egg overspray with tebuconazole significantly increased chick mortality, which was 26% higher than that of controls. 2,4-D caused a similar but a close to significant increase (chick mortality 24% higher than controls). Exposure to either pesticide through contact with treated soils did not affect chick survival but altered some biochemical parameters posthatching. Our experiment shows that egg spraying with pesticides should be considered as a relevant exposure scenario in risk assessment procedures, given its potential to affect the reproductive success of ground-nesting farmland birds.

Risk Assessment of Cd, Cu, and Pb from the consumption of hunted meat: red-legged partridge and wild rabbit.

The objective was to assess that potential health risk from Cd, Cu, and Pb, through the consumption of hunted red-legged partridge and wild rabbit meat, with special focus on the population of hunters and their relatives. Mineral content was analyzed by atomic absorption methods (F-AAS for Cu and GF-AAS for Cd and Pb) after microwave digestion of lyophilized samples. The average concentrations of these elements were 0.008 and 0.01 mg/kg for Cd; 1.41 and 1.63 mg/kg for Cu and 0.98 and 1.28 mg/kg for Pb in wild rabbit and red-legged partridge meat respectively. The dietary, risk assessment was performed by assuming two intake scenarios based on the obtained results of the survey on game meat consumption and the current maximum recommended intakes of Cd, Cu, and Pb, and then, the hazard quotients (THQ and TTHQ) were calculated. The data show that exposure to these metals from eating red-legged partridge and wild rabbit meat from a hunting provenance is relatively low and generally greater in the hunter population. The risk assessment revealed that moderate or low consumption of meat of these species does not offer a significant public health risk. Moreover, hazard quotients values for these metals of red-legged partridge and rabbit meat consumption in hunters and nonhunters are below 1. However, a high Pb content in the meat of these species and a high consumption may pose a greater health risk to hunters.

Life-long testosterone and antiandrogen treatments affect the survival and reproduction of captive male red-legged partridges (Alectoris rufa)

Sexual steroids can play an important role as life-history organizers. In males, high circulating testosterone levels induce physiological/behavioral costs and benefits, leading to trade-offs. However, studies simultaneously testing the impact of these levels in both fitness components (survival and fecundity) during lifetime are scarce and limited to wild birds. To determine the mortality causes or hormonal manipulation impacts on male fertility is, nonetheless, a difficult task in free-ranging animals that could be easier in captivity. We longitudinally monitored captive red-legged partridges (Alectoris rufa) and exposed males to high exogenous testosterone levels, anti-androgens, or a control treatment during each breeding period throughout their lives. Theory predicts that individuals maintaining high androgen levels should obtain higher fitness returns via reproduction, but suffer reduced longevity. Testosterone-treated male partridges, accordingly, lived shorter compared to controls, since they were more prone to die from a natural bacterial infection. However, the same birds seemed to have a lower capacity to fertilize eggs, probably due to endocrine feedback reducing testicular mass. These results show that exogenous testosterone can exert unpredicted effects on fitness parameters. Therefore, caution must be taken when drawing conclusions from non-fully controlled experiments in the wild. Males treated with the androgen-receptor blocker flutamide did not outlive controls as predicted by the life-history trade-off theory, but their mates laid eggs with higher hatching success. The latter could be due to mechanisms improving sperm quality/quantity or influencing maternal investment in egg quality. Testosterone receptor activity/amount could thus be as relevant to fitness as testosterone levels.Significance statementIt has repeatedly been hypothesized that high testosterone levels induce a cost in terms of reduced lifetime reproductive success. This can be due to reduced fecundity or via shorter lifespan. This is, however, only supported by a handful of studies, mostly in wild birds. We tested this in captive male red-legged partridges, which allowed us to determine reproductive success and mortality causes. We increased testosterone levels or blocked its action with antiandrogens throughout life. High testosterone levels reduced the survival by making birds more prone to die by infection. The eggs produced by their mates also showed lower hatching success, a probable manipulation artifact that should be considered in avian studies in the wild. Interestingly, the androgen-receptor blocker flutamide increased lifetime hatching success compared to controls, suggesting that androgen receptor amounts/activity are even more relevant to fitness than testosterone levels.

Multi-level analysis of exposure to triazole fungicides through treated seed ingestion in the red-legged partridge

Triazole fungicides are the most widely used products to treat cereal seeds. Granivorous birds, such as red-legged partridges (Alectoris rufa), which consume seeds left on the surface of fields after sowing, have a high risk of exposure. As triazole fungicides can affect sterol synthesis, we tested the hypothesis that treated seed consumption could alter the synthesis of sex hormones and reduce the reproductive capacity of partridges. We exposed adult partridges to seeds treated with four different formulations containing triazoles as active ingredients (flutriafol, prothioconazole, tebuconazole, and a mixture of the latter two) simulating a field exposure during the late autumn sowing season. All treatments produced biochemical changes and an overexpression of genes encoding for enzymes involved in the biosynthesis of sterols and steroid hormones, such as PMVK, ABCA1, MVD, PSCK9, DHCR7 and HSD17B7. Plasma levels of oestradiol were reduced in partridges exposed to tebuconazole. We also monitored reproduction 3 months after exposure (laying date, egg fertilization and hatching rates). We observed a 14-day delay in the laying onset of partridges that had been exposed to flutriafol as compared to controls. These results show that the consumption of seeds treated with triazole fungicides has the potential to affect granivorous bird reproduction. We recommend the evaluation of lagged reproductive effects as part of the protocols of environmental risk assessment of pesticides in wild birds in light of the effects resulting from the exposure to triazole-treated seeds.

Protozoan and Helminth Infections of Aviary-Reared Alectoris rufa (Galliformes: Phasianidae) before Releasing for Hunting in the Czech Republic: Infection Dynamics and Potential Risks.

Age-related dynamics of protozoan and helminth infections in the red-legged partridge, Alectoris rufa, were studied in an intensive breeding aviary in the Czech Republic before releasing birds for hunting purposes. Pooled fecal samples (n = 900) were examined over 3 rearing seasons (2012-2014). A total of 4 protozoan species, Cryptosporidium baileyi, Cryptosporidium meleagridis, Eimeria kofoidi, and Eimeria legionensis, and 4 helminths, Capillaria phasianina, Eucoleus perforans, Heterakis gallinarum, and Syngamus trachea, was found. The most common parasite was S. trachea (prevalence 20-26%) in dead birds (n = 99), which represents a high risk for breeders. Co-occurrence of protozoans and helminths indicated similarities in infection dynamics throughout the 3 breeding seasons. Mixed infections of Cryptosporidium baileyi and C. meleagridis with other parasitic species are reported for the first time. Our findings provide new insights into breeding of A. rufa and may help to improve the efficacy of disease control strategies and prevention, especially with the potential for spreading of parasitic infections to wildlife through released birds into open areas.

Interspecific competition between two partridges in farmland landscapes

Interspecific competition is expected to occur between phylogenetically closely related species when sharing resources. In birds, interspecific competition often occurs by song-mediated interference and frequently implies asymmetrical outcomes between the species pairs involved. Habitat loss resulting from agricultural intensification is expected to have aggregated bird species in the remaining suitable habitats, thus increasing the likelihood of interspecific competition. However, this process has rarely been considered as a potential factor limiting population recovery in farmland birds. We investigated whether interspecific competition occurs between grey, Perdix perdix, and red-legged, Alectoris rufa, partridges, two phylogenetically related species. Originally parapatric, they have suffered an artificial increase in their contact zone due to huge human-mediated gamebird releases. We analysed territorial behaviour through a playback stimuli experiment and investigated shifts in habitat niche in the absence and presence of a hypothetical competitor. Results showed that the grey partridge appeared less territorial when co-occurring with the red-legged partridge and shifted its habitat niche away from the latter, while no such change was detected for the red-legged partridge. These asymmetrical patterns in behaviour and ecology are predicted under an interspecific competition scenario beneficial to the red-legged partridge, and therefore suggest that they are competitively dominant to grey partridges where they co-occur. This result has potentially strong implications for the management of grey partridges as gamebirds, and for their conservation in areas where they are almost extirpated.

Feathers and hair as tools for non-destructive pollution exposure assessment in a mining site of the Iberian Pyrite Belt

Mining is responsible of releasing trace elements to the environment with potential negative effects on wildlife. Traditionally, wildlife exposure assessment has been developed by analyzing mainly environmental compartments or internal tissues. Nowadays, the use of non-destructive matrices such as hair or feathers has increased. Nevertheless, its use in free-living terrestrial mammals or in birds other than raptors or passerines is less frequent. The main objective of our study was to determine the potential for hair and feathers in a rabbit and bird species to be used as non-invasive proxy tissues for assessing internal metal concentrations at polluted sites from mining. We tested whether hair of European rabbit (Oryctolagus cuniculus) and feathers of red-legged partridge (Alectoris rufa) can be used as non-destructive biological monitoring tools of both essential (Cu, Zn) and non-essential (Pb, Cd, As) trace elements in a currently active copper mining site. We found significant different concentrations, particularly in non-essential elements, between reference area and mining site. Non-essential elements Pb and Cd showed higher correlations between tissues and hair/feathers, while few significant patterns were observed for essential elements such as Cu and Zn. Although feathers showed lower levels of correlation with internal tissues than hair, both could be useful as non-destructive biological monitoring tools. Further tissues, and more importantly, hair and feathers allowed discrimination between polluted and reference sites to indicate bioavailability and pollution status. In addition, hair and feathers can be used in monitoring pollution of an active mining site, being specially interesting for biomonitoring a certain period of time in the event of a particular episode of pollution, in addition to the chronic exposure. As occurred with hair in rabbits, feathers seem to be a good compartment to detect differences between a potential polluted area, such the surrounding of an active mine site, and a non-polluted area.