Search

Knowledge of seasonal variation in hunting pressure and the demographic composition of hunting bags is likely to be important for the effective management of quarry species. Such knowledge is particularly important where regulatory mechanisms aim to avoid the over-exploitation of quarry species having unfavourable conservation status. We compiled information on the age composition of harvested European Turtle-doves (Streptopelia turtur), and the daily numbers of doves shot and retrieved from 68 hunting estates spread across four Spanish regions. We use these data to describe temporal variation, and identify factors affecting daily hunting bags, age composition and crippling losses. We found that more juvenile doves were hunted than adults (and more than expected in a stable population) especially at the beginning of the hunting season, suggesting greater vulnerability of juveniles to hunting. The number of doves hunted each day declined through the hunting season and increased with the number of hunters present. Crippling losses averaged 9.6 % of all doves shot; applying this rate to recent Spanish government hunting statistics suggests under-recording of approximately 90,000 doves annually for the entire country. Our data on age composition and crippling losses can serve as direct inputs into future models of sustainable harvest for Turtle Dove in Europe. Our results highlight the importance of improving knowledge about the variables influencing take at the hunting event level for designing more efficiency regulatory measures.

Ante el declive de la Tórtola Común (Streptopelia turtur), se valora la presión cinegética ejercida sobre la especie en Extremadura. Se analizan datos de 113 cacerías desarrolladas en toda la región durante la media veda de 1999. Los resultados se comparan con otros de las temporadas 1996 y 1997. Se pone en evidencia una excesiva presión cinegética ya que se cazan hasta 2,4 veces más jóvenes que los que se producen. Hay una tendencia de disminución de las capturas estandarizadas (8 ejemplares en 1996 a menos de 4 en 1999). También se analiza y discute la proporción de jóvenes abatidos respecto a adultos, la incidencia de las fechas de la media veda y la casuística decapturas y tipos de cazadores., Usapal arruntaren (Streptopelia turtur) gainbehera dela eta, Extremaduran espezie horren gainean eginiko presioa baloratzen dugu. Eskualde osoan 1999ko debekaldi erdian eginiko 113 ehizaldiren datuak aztertzen dira lan honetan. Emaitza horiek 1996 eta 1997ko denboraldietakoekin konparatzen dira. Begien bistakoa da presio zinegetikoaren gehiegizkoa, ehizatzen diren aleak ekoizten direnak baino 2,4 aldiz gazteagoak baitira. Kopuru atzemate estandarrak jaitsi dira (8 ale 1996an, 4 baino gutxiago 1999an). Halaber, honako hauek aztertu eta eztabaidatzen dira: harrapaturiko ale gazteen proportzioa helduekiko, debekadi erdiaren daten garrantzia eta atzemate zein ehiztari moten kasuistika., Face au déclin de la Tourterelle des Bois (Streptopelia turtur), on évalue la pression cynégétique exercée sur l'espèce en Extrémadure. On analyse des données de 113 parties de chasse qui se sont déroulées dans toute la région durant la demi fermeture de 1999. Les résultats se comparent avec d'autres de la période 1996 et 1997. On meten évidence une pression cynégétique excessive puisque l'on chasse jusqu'à 2,4 fois plus de jeunes qu'il n'en naît. Il y a une tendance de diminution des captures standarisées (8 exemplaires en 1996 à moins de 4 en 1999). On analyse et on discute également la proportion de jeunes abattus en comparaison avec les adultes, l'incidence des dates de la demi fermeture et la casuistique des captures et des types de chasseurs., Considering the decline of the Turtle Dove (Streptopelia turtur), an assessment is made of the cynegetic pressure exercised on this species in Extremadura. An analysis is carried out of data from 113 hunting runs carried out all over Extremadura during the 1999 season. The results are compared with those from the 1996 and 1997 seasons. Such studies reveal an excessive cynegetic pressure since the number of hunted birds exceeds in up to 2,4 times the number of birds reproduced. There is a decreasing trend in standardised captures (from 8 samples in 1996 to less than 4 in 1999). There is also an analysis and a discussion on the proportion of young as opposed to adult birds, the incidence of hunting season dates, capture casework and types of hunters.

La utilización del alimento como atrayente o reclamo de tórtolas y otras aves es una práctica de gestión reciente y actualmente muy extendida en España, a pesar de estar prohibida por la legislación vigente. En el presente trabajo se analiza la utilización de dichos reclamos y su efecto sobre la Tórtola. Para ello se realizó el seguimiento completo de 113 cacerías repartidas por toda Extremadura durante 1999. Los reclamos más utilizados son el trigo y el girasol, así como las mezclas de ambos y con otras semillas (maíz, veza, mijo, etc). La proporción de jóvenes abatidos respecto a adultos es mucho mayor en las zonas donde se utilizan atrayentes que donde no se utilizan, siendo el girasol el tipo de cebo con efectos más negativos para la especie., Usapalen eta beste zenbait hegaztiren erakargarri edo abata gisa elikagaia erabiltzea gestio-praktika berria da eta gaur egun oso hedatua dago Espainian, nahiz eta indarrean den legerian debekaturik egon. Lan honetan abata horien erabilera eta Usapalaren gainean duten eragina aztertzen dira. Horretarako, 1999 urtean Extremadura guztian banaturiko 113 ehizaldiren jarraipen osoa egin zen. Garia eta ekilorea, bai eta biak nahasirik edo beste ale batzurekin (artoa, zalke, artatxiki, etab.) eginiko nahasketak dira gehien erabilitako abatak. Gazteen proportzioa helduekiko askoz handiagoa da erakargarriak erabiltzen diren lekuetan erabiltzen ez direnetan baino, eta ekilorea da espeziearentzat eraginik negatiboena duena., L'utilisation de l'aliment en guise d'appat de tourterelles et autres oiseaux est une pratique de gestion récente et actuellement très répandue en Espagne, bien qu'elle soit interdite par la législation en vigueur. Dans ce travail on analyse l'utilisation de ces appats et leur effet sur la Tourterelle. On a réalisé pour cela le suivi complet de 113 parties de chasse réparties dans toute l'Extrémadure durant 1999. Les appats les plus utilisés sont le blé et le tournesol, ainsi que les mélanges des deux avec d'autres graines (maïs, petit pois, millet, etc.). La proportion de jeunes abattus est beaucoup plus grande que celle des adultes dans les zones où l'on utilise ces appats que dans les zones où on ne les utilise pas. Le tournesol est la graine qui a le plus d'effets négatifs pour l'espèce., The use of food as an attraction for turtle-doves and other species is a recent management practice, which is currently very extended throughout Spain, in spite of its prohibition in the legislation in force. In the present work, the authors analyse the use of such attractions and their effect on the Turtle Dove. In order to do so, a thorough monitoring of 113 hunting grounds disseminated all over Extremadura was carried out during 1999. The lures that were used the most were wheat and the sunflower seeds, as well as the mixtures of both and with other seeds (corn, vetch, millet, etc). The proportion of young birds shot down is much greater with respect to adult birds in areas in which such attractions are used, as opposed to where they are not, sunflower seeds being the kind of lure that produces the most negative effects for the species.

Since its detection in China in 1984, rabbit haemorrhagic disease (RHD) has been the subject of numerous studies. Yet, the evolutionary origin of rabbit haemorrhagic disease virus (RHDV) is still under debate. For example, some aspects related to the epidemiology of the disease are still unknown, such as where the virus is hosted between RHD outbreaks. To detect the presence of RHDV in rabbit-sympatric micromammals, 51 rodents (29 Mus spretus and 22 Apodemus sylvaticus) and 31 rabbits (Oryctolagus cuniculus) from the same location in central Spain were analyzed. In those samples in which the virus was detected, a fragment of the VP60 protein gene from the RHDV capsid was sequenced and the phylogenetic relationships between them and other strains of RHDV in the Iberian Peninsula were analyzed. In total, five viral strains were identified in A. sylvaticus, M. spretus and O. cuniculus. All strains were found to be well supported within the clade of RHDV found in rabbits in the Iberian Peninsula. Moreover, one of the strains was found in all three species under study, which suggests the capability of RHDV to infect other mammals apart from the rabbit which have not yet been investigated. The transmission of the virus is discussed as well as its ecoepidemiological implications.

[Background]: Rabbit haemorrhagic disease virus (RHDV) is a highly virulent calicivirus, first described in domestic rabbits in China in 1984. RHDV appears to be a mutant form of a benign virus that existed in Europe long before the first outbreak. In the Iberian Peninsula, the first epidemic in 1988 severely reduced the populations of autochthonous European wild rabbit. To examine the evolutionary history of RHDV in the Iberian Peninsula, we collected virus samples from wild rabbits and sequenced a fragment of the capsid protein gene VP60. These data together with available sequences from other Western European countries, were analyzed following Bayesian Markov chain Monte Carlo methods to infer their phylogenetic relationships, evolutionary rates and demographic history. [Results]: Evolutionary relationships of RHDV revealed three main lineages with significant phylogeographic structure. All lineages seem to have emerged at a common period of time, between ~1875 and ~1976. The Iberian Peninsula showed evidences of genetic isolation, probably due to geographic barriers to gene flow, and was also the region with the youngest MRCA. Overall, demographic analyses showed an initial increase and stabilization of the relative genetic diversity of RHDV, and a subsequent reduction in genetic diversity after the first epidemic breakout in 1984, which is compatible with a decline in effective population size. [Conclusions]: Results were consistent with the hypothesis that the current Iberian RHDV arose from a single infection between 1869 and 1955 (95% HPD), and rendered a temporal pattern of appearance and extinction of lineages. We propose that the rising positive selection pressure observed throughout the history of RHDV is likely mediated by the host immune system as a consequence of the genetic changes that rendered the virus virulent. Consequently, this relationship is suggested to condition RHDV demographic history.

[EN] The European turtle dove (Streptopelia turtur) is an important gamebird in south-western Europe, and in some areas a significant proportion of hunting grounds conduct targeted management aiming to increase its breeding densities and hunting opportunities, mainly through food provision. Using harvest data from managed grounds, we estimated the productivity (juvenile/adult ratio), the harvesting levels and the local turtle dove abundance before the hunting season, the latter being compared to the number of birds observed by hunters in food plots. Our research found high values of productivity and significant differences between the estimated abundance and the number of birds observed by hunters, which suggests that in a high proportion of grounds, the latter method may have led to bird overestimation and overharvesting. As managed grounds for the turtle dove may increase the productivity and recruitment of the species, it is crucial to ensure sustainable harvesting through (1) bird monitoring based on transects to calculate abundance and (2) promoting regulations to adjust the number of hunting days.

Background Avian trichomonosis is known as a widespread disease in columbids and passerines, and recent findings have highlighted the pathogenic character of some lineages found in wild birds. Trichomonosis can affect wild bird populations including endangered species, as has been shown for Mauritian pink pigeons Nesoenas mayeri in Mauritius and suggested for European turtle doves Streptopelia turtur in the UK. However, the disease trichomonosis is caused only by pathogenic lineages of the parasite Trichomonas gallinae. Therefore, understanding the prevalence and distribution of both potentially pathogenic and non-pathogenic T. gallinae lineages in turtle doves and other columbids across Europe is relevant to estimate the potential impact of the disease on a continental scale. Results We examined 281 samples from four wild columbid species for Trichomonas infection and determined the genetic lineages. The overall prevalence was 74%. There were significant differences between the species (P = 0.007). The highest prevalence was found in stock doves Columba oenas (86%, n = 79) followed by wood pigeons Columba palumbus (70%, n = 61) and turtle doves (67%, n = 65), while three of five collared doves Streptopelia decaocto (60%) were infected. We found seven different lineages, including four lineages present in columbids in the UK, one lineage already described from Spain and three new lineages, one of those found in a single turtle dove migrating through Italy and another one found in a breeding stock dove. Stock doves from Germany and collared doves from Malta were infected with a potentially pathogenic lineage (lineage A/B), which is known to cause lesions and mortality in columbids, raptors and finches. Conclusions Generally, turtle doves showed high prevalence of Trichomonas infection. Furthermore, the potentially pathogenic lineage A/B (or genotype B according to previous literature) was found in a recovering stock dove population. Both findings are worrying for the