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In order to monitor wildlife populations in a manner that supports policy makers and natural resource managers, data must be collected using frameworks and methodologies that allow for comparisons between projects and across time. Though hunting statistics may represent a reliable data source for monitoring population trends in game species, a standardised framework for collecting and analysing this data has never been established in Europe, even within countries. Here we describe a case study on the use of hunting statistics in Spain in order to (i) describe the variability in big game statistics collection frameworks across mainland regions of Spain and (ii) propose a minimum common denominator for a standardised approach at the country level. The main differences in methodologies identified are that each region collects different variables, uses different spatial and temporal resolution, and follows different methodologies. We described spatial patterns by grouping regions based on similarities in the hunting data collection system and identified socio-economic factors as a potential driver of differences in methodologies among regions. Hunting effort-related variables and improved temporal resolution (to the event level) must be incorporated in order to achieve country-level standardisation of methodologies. The use of application software to collect information from the field in a standardised way is recommended, which necessitates engaging stakeholders as part of the monitoring process. Applications software should be designed intentionally, and only after clear objectives for the monitoring program have been defined. Making hunting data open access will improve collaboration and information transfer to scientific and professional sectors. Our recommendations can be adapted to other European countries, which would make hunting data more useful for population monitoring and wildlife policy-making at large spatial scales. Initiatives such as the “European Wildli

The red-legged partridge, as the other Alectoris partridges, is an appreciated game bird subject to intensive management and high hunting demand. Red-legged partridges are raised on game farms, often if not always being hybridized with more prolific chukar partridges, to be released into natural populations for shooting. Massive captive rearing and releasing of partridges is not only homogenizing the natural genetic structuring of wild populations but also contaminating the gene pool of the red-legged partridge with the genome of the exotic chukar partridge. We review analytical approaches used to detect partridge hybridization and describe the status of anthropogenic hybridization in wild and farm populations. Finally, we assess the evidences of the fitness consequences of hybridization or domestication on red-legged partridge populations and incorporate some considerations and concerns about the use of current molecular tools to manage and research partridge genetic integrity.

Thanks to the Pan-European Common Birds Monitoring Scheme and Breeding Bird Survey, the temporal changes in abundance of the Red-legged Partridge are known in most countries of its area of distribution. However, these are based on abundance indices and no strong inference is possible about potential causes of local trends. Robust estimates of abundance or densities at national scale are still lacking. Information from hunting bags cannot be used owing to the inclusion of released Red-legged Partridges in those numbers. Even in the absence of released individuals in hunting bags, these estimates cannot be used owing to a lack of knowledge of variations in reporting behaviour in Europe and potential age-specific mortality. Numbers at the local scale are obtained using similar (although not equal) methods across countries based on line/point transect methods. Given that some capture-recapture studies have been carried out from time to time in most of the distribution range, their results could help to estimate the demographic parameters required for management. Finally, given that these common methods are applied with, possibly, some avoidable differences, a more integrative strategy of methodological design and spatial sampling may make it possible to extrapolate estimates from regional to national/continental scale, and to provide assessments of abundance as well as spatial and temporal variation in Red-legged Partridge population size. This global approach may increase the current value of monitoring to all stakeholders interested in Red-legged Partridges.

Predation is just one of several possible causal factors of the red-legged partridge decline. It is a key factor affecting the success of red-legged partridge nests, but agricultural activities can be the main cause of nest loss in some areas. Because hatchlings are more vulnerable to predation, this stage represents a critical bottleneck for partridge populations. Most restocking programmes fail due to predation due to the partridges’ inability to adapt to the new situation. Although predator control is a widespread game management practice for the red-legged partridge it has limited effects in most management situations. Some measures indirectly affecting the effects of predation, such as habitat management, could represent a long-lasting measure for reducing partridge predation preferable over traditional predator control, and they could revert current negative trends.

A recent publication by Carvalho et al. in “Virus Genes” (June 2017) reported the presence of the new variant of rabbit hemorrhagic disease virus (RHDV2) in the two larger islands of the archipelago of Madeira. Based on the capsid protein sequence, the authors suggested that the high sequence identity, along with the short time spanning between outbreaks, points to dissemination from Porto Santo to Madeira. By including information of the full RHDV2 genome of strains from Azores, Madeira, and the Canary Islands, we confirm the results obtained by Carvalho et al., but further show that several subtypes of RHDV2 circulate in these islands: non-recombinant RHDV2 in the Canary Islands, G1/RHDV2 in Azores, Porto Santo and Madeira, and NP/RHDV2 also in Madeira. Here we conclude that RHDV2 has been independently introduced in these archipelagos, and that in Madeira at least two independent introductions must have occurred. We provide additional information on the dynamics of RHDV2 in the Macaronesian archipelagos of Azores, Madeira, and the Canary Islands and highlight the importance of analyzing RHDV2 complete genome.

Understanding the spatial pattern of genetic diversity may be pivotal to adaptive conservation management of a given taxon. The red-legged partridge (Alectorisrufa, Linnaeus 1758) is naturally widely distributed from the Mediterranean to humid temperate zones. According to a recent study, the genetic structure of this species comprises five clusters, three of which are in the Iberian Peninsula (glacial refugia). Partridge demographic expansion events and climatic shifts during Pleistocene glaciations have been used to test the hypotheses concerning Iberian red-legged partridge distribution. We tested the existence of climatic and geographic relationships on genetic diversity/distances. We employed markers from two different genetic systems, such as part of the mitochondrial DNA control region (n = 113) and 20 species-specific microsatellite DNA loci (n = 377), including climatic and geographic factors from the 14 Iberian localities where A. rufa populations were sampled. Our results showed a mitochondrial genetic diversity pattern associated with a thermic gradient, and a decrease of genetic diversity in peripheral populations that concurred with the ‘abundant centre’ hypothesis. Overall, current climatic variables reliably described genetic variation and differentiation in the red-legged partridge, which may be a result of local species adaptation.

Hyperpredation can be described as a restrictive case of apparent competition where an increased number of primary prey species indirectly induces the decrease of the secondary prey species through numerical response of predators to the primary prey dynamics. It has been proposed that rabbit hemorrhagic disease (RHD), which decimated populations of European wild rabbit (Oryctolagus cuniculus) in Spain, led to prey switching by raptors towards red-legged partridges (Alectoris rufa) causing declines in their populations as a peculiar case of hyperpredation. We have reviewed field studies that disagree with estimates (based on bag records) of recent increases of rabbit and partridge numbers in Spain. Because of an increase in releases of farm-reared animals, there is doubt about the use of bag records to accurately estimate population trends in recent decades. We also provide new data and discuss some analytical considerations related to the temporal and spatial scales that might affect the interpretation of data. Finally, we discuss why studies associated with raptor food habits, predator population dynamics and predator distribution suggest that diet data are not sufficient to link patterns and processes. Although we agree that the RHD outbreak has markedly affected rabbit populations, which has indirectly affected many other species in the Iberian Peninsula, we consider that hyperpredation mediated by raptors has not been clearly demonstrated. In contrast, endorsing the hypothesis of raptor-mediated hyperpredation without sufficient proof may have conflictive consequences if we consider the increased persecution of raptors in recent decades in Spain.