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Valverde, J. A. 1957. |
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Ecological notes on the Spanish lynx: environment & biocoenosis, the place of the lynx in the biocoenosis of the Coto Doñana, prey, food habits, competitors, reproduction. |
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Valverde, J. A. 1963. |
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Information on the Spanish lynx: description, distribution, biology, research programs, collaboration. |
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Van den Brink, M. F. H. 1971. |
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Reflections on the assumption that the Pardel lynx (Lynx pardina) is an own species, rather related to the bobcat (Lynx rufus) than to the Eurasian lynx (Lynx lynx). |
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van der Loo, W., Ferrand, N.,
and Soriguer, R. C. 1991. |
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The minimal gene diversity at a locus of the antibody constant region, as estimated in natural populations of rabbit, revealed levels of heterozygosity similar to those reported for the major histocompatibility complex in human and murine populations. Sera of 416 wild rabbits were collected on the Iberian peninsula and on three islands of the Azorean archipelago and analyzed for the occurrence of the serological markers of the b locus of the immunoglobulin light chain. All four serotypes present in domestic rabbits were found in Portugal. They represented less than 50% of the gene pool. In Andalusia this was less than 15% and on the Azorean islands less than 10%. The pronounced and systematic hierarchy in allele frequencies, previously found in populations form the more recent distribution area of the species, was not observed. On the peninsula, the frequencies of the "domestic" alleles were similar, averaging 10%. The Portuguese sample revealed a total heterozygosity of at least 87%. This high value was supported by at least 11 serologically different alleles, none of them occurring at frequencies above 20%. These data are in agreement with an Iberian origin of the European rabbit and strongly suggest the coalescence of b locus allelic lines drawn from Iberian and western populations. The role of balancing selection in the evolution of the b locus polymorphism was further emphasized. |
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van_der_Loo_et_al_1991_Immunoglobulin_gene_diversity_in_rabbit.pdf |
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Vargas, A. and Heredia, B. 2001. |
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Content: Planning for the Iberian Lynx Ex-situ conservation program; Founder population: numbers, origin, and placement; Program organization, management, and financial support; Current status. |
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Vargas_&_Heredia_2001_Captive_Breeding_Plan_for_Iberian_Lynx_-_Cat_News_No34.pdf |
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Vargas, A., Martínez, F., Bergara, J., Klink, L.
D., Rodriguez, J. M., Simon Mata, M. A., and Aymerich, M. 2005. Programa de conservación Ex-Situ del Lince Ibérico. Medio Ambiente 49 [Verano / 2005]: 6-11. Junta de Andalucía, Consejería de Medio Ambiente. |
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The breeding for the
conservation of endangered species is an expensive conservation tool that
requires a careful planning to secure its integration in the global strategy
for the recovery of the species. Once the necessity to initiate an ex-situ
conservation programme is established, it is fundamental to prevent putting the
in-situ conservation measures at risk. A breeding programme should only be
started when the necessary administrative support, the financial resources and
the adequate infrastructures to achieve it are consolidated. It is considered
important that a planning of the programme bases in short- and long-term
objectives in which aims concerning the genetic and demographic management in
captivity are included, and which in its turn respects the sanitary,
reproductive and ethological aspects of the captive population. |
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| © Programa de conservación Ex-Situ del Lince Ibérico |
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Vigne, J. D., Biju-Duval, C., Soriguer, R. C.,
Dennebouy, N., and Monnerot, M. 1994. |
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In order to understand the structure and origin of the present distribution of wild rabbits in Western Europe, we intend to characterize each population by sampling and recording a set of biological variables for each. In the present study, a population from southern Spain is used as an example. Biological parameters considered were general size and allometries, hematology, serum biochemistry, osteological morphology, and mitochondrial DNA. The range of each variable is described and its biological meaning discussed. This set of variables seems to be of use in population characterization. Furthermore, the recent history of the population can be explored by reference to bones from nearby archeological sites. |
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Vigne_et_al_1994_Multiple_characterization_of_a_rabbit_population.pdf |
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Villafuerte, R. 2002. |
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Basic information on the Rabbit in Spain: Taxonomy, description, distribution, habitat, reproduction, feeding habits, abundance, social organization & behaviour, economic interests & relation to humans, threats. |
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Villafuerte_2002_Oryctolagus_cuniculus_en_Espana_Atlas_Mamiferos.pdf |
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Villafuerte, R. and Moreno, S.
1997. |
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As European rabbits Oryctolagus cuniculus in SW Spain face high predation pressure, some antipredator tactics are espected. We examined rabbit group size in relation to the safety of the cover (sparse or dense), and the proximity to shrub cover. Stem density influenced the distance rabbits ventured from shrub; rabbits ventured greater distances when stem density in cover was higher. Rabbit group size was related to the distance to cover; solitary animals remained closer to protective cover, whereas rabbits in groups (=/>3 animals) foraged further from cover. These results are consistent with the hypothesis that the formation of rabbit groups is related to defense against predation, and that group size is influenced by risk of perception. |
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Villafuerte_&_Moreno_1997_Predation_risk_in_rabbits_Donana.pdf |
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Villafuerte, R. and Viñuela,
J. 1999. |
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Rabbits are the staple prey for Black Kites in Matasgordas, south-western Spain. Because of their poor predator skills, it has been considered that most of the Rabbits consumed by Kites were young and affected by myxomatosis. After rabbit haemorrhagic disease (RHD) arrived in Spain, and since most of the Rabbits affected were adults, it was expected that the raptor would benefit with the incorporation of larger Rabbits in its diet. In concordance with that prediciton, during the immediate three years before the arrival of RHD (1987-89), average size of those Rabbits consumed by nestling Black Kites were similar and corresponded to the size of those Rabbits affected by myxomatosis. However, after RHD arrival in 1990, sizes of Rabbits consumed by Kites increased, corresponding to the age more frequently affected by RHD. |
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Villafuerte_&_Vinuela_1999_Size_of_Rabbits_consumed_by_Black_Kites.pdf |
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Villafuerte, R., Kufner, M.
B., Delibes, M., and Moreno, S. 1993. |
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Activity pattern of European wild rabbits has been studied in a Mediterranean ecosystem of SW Iberian Peninsula, from where they are a native species. The daily activity pattern of rabbits in the area is similar to those found in other countries where the species has been introduced: high activity at night and at twilights, and scarce activity by day. However, this general pattern shows seasonal changes probably related to environmental conditions and antipredatory strategies. Changes in rabbits activity are correlated mainly with temperature, but sunlight, moonlight, and wind also affect it. Variations of activity pattern suggest that controlling mechanisms are flexible enough to allow adaptations to changing environments. |
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Villafuerte_et_al_1993_Environmental_factors_influencing_seasonal_daily_activity_of_rabbit.pdf |
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Villafuerte, R., Calvete, C.,
Gortázar, C., and Moreno, S. 1994. |
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The first known epizootic of rabbit hemorrhagic disease (RHD) occured in two free-living wild rabbit (Oryctolagus cuniculus) populations at Doñana National Park, Spain. Rabbit population density was not correlated to RHD mortality. Only adult animals were affected; males and females had similar mortality rates. |
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Villafuerte_et_al_1994_First_epizootic_of_rabbit_hemorrhagic_disease_in_Donana_NP.pdf |
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Villafuerte, R., Calvete, C.,
Blanco, J. C., and Lucientes, J. 1995. |
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The current distribution and rate of spread of rabbit hemorrhagic disease (RHD) has been studied in Spain using interviews with hunters and conservationists and field surveys. The disease is currently present throughout Spain. A low rate of expansion (2-15 km per month), yet long distance between simultaneous outbreaks, suggests human-related transmission of RHD. The disease appears annually, mainly during spring (52.5%) and winter (33.8%). Most of the interviewees (63%) indicated that the first outbreak of the disease caused greater mortalities than successive outbreaks. To investigate this, we estimated the mortality rate from RHD of one locality, six years after the initial outbreak. The mortality rate was approximately 30%, and lower than that estimated during the first outbreak of RHD (55-75%). Few populations of rabbits (7.5%) have returned to levels they held prior to the onset of the disease. Recovery ws greater among dense populations. Most sites with low population of rabbits prior to the arrival of HD have not recovered. |
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Villafuerte_et_al_1995_Incidence_of_viral_hemorrhagic_disease_in_rabbit.pdf |
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Villafuerte, R., Luco, D. F.,
Gortázar, C., and Blanco, J. C. 1996. |
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In this paper, we studied the effect of rabbit decline due to RHD on red fox, measuring red fox litter size and fox diet at two areas with different rabbit density before and after RHD in north-eastern Spain. |
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Villafuerte_et_al_1996_Red_fox_litter_size_and_diet_after_rabbit_haemorrhagic_disease.pdf |
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Villafuerte, R., Lazo, A., and
Moreno, S. 1997. |
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In this paper, we present data on rabbit abundance at Doñana National Park during a 25-month period, in the middle of which occurred the first RHD outbreak. We analyse the relationship of rabbit numbers with food abundance and quality, discussing the current management attitudes applied in Doñana to maintain rabbits as an abundant species. |
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Villafuerte_et_al_1997_Influence_of_food_abundance_and_quality_on_rabbit_fluctuations.pdf |
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Villafuerte, R., Viñuela, J.,
and Blanco, J. C. 1998. |
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The European rabbit Oryctolagus cuniculus , an important game species in Spain, has declined sharply since the arrival of haemorrhagic disease in 1988. As a consequence of this decline, it appears that illegal and extensive persecution of predators has increased. We have assessed the impact of this persecution on red kites Milvus milvus . Around 90% of the populations studied have declined during the last 3-10 years, and the species' range has been reduced since 1980, particularly in high rabbit density areas (those most valuable for hunters). Currently, stable or increasing populations of red kites are located in areas of low rabbit density. Their abundance in areas of high rabbit density is similar to that recorded during the 1970s. when, after the spread of myxomatosis over Spain, government- sponsored campaigns of vermin extermination were carried out. Although red kites cannot be considered important predators of rabbits, they are suffering the effects of human persecution, because of their susceptibility to shooting and poisoning, and a lack of understanding among hunters. We discuss the management strategies that might be used during population crashes of game species to avoid unjustified persecution of predators. |
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Villafuerte_et_al_1998_Red_kite_persecution_and_rabbit_population_crash.pdf |
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Viñuela, J., Villafuerte, R., and De le Court, C.
1994. |
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Previous studies have shown that the rabbit (Oryctolagus cuniculus) is the main prey of the Black Kite (Milvus migrans) in Matasgordas (Doñana National Park, southwestern Spain), and that the reproductive success of pairs is enhanced with increasing rabbit consumption. In our study area, rabbits live mainly in large warrens patchily distributed across the breeding area of Black Kites. Rabbit consumption was higher for Black Kite pairs having warren entrances close to their nests. During the 3 years of the study, this population of Black Kites suffered a considerable increase. New pairs in the area selected nesting trees inside areas with a high density of rabbits. The pattern of Black Kite aggregation in out study areas, where they breed in a "colony" with a population density among the highest recorded, can be explained, at least partially, by rabbit aggregation. Defense of feeding resources could help to explain the territorial behavior of Black Kites. Coloniality and feeding territoriality are not mutually exclusive. |
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Vinuela_et_al_1994_Nesting_dispersion_of_Black_Kite_in_relation_to_rabbit_warrens.pdf |
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Virgós, E., Telleria, J. L.,
and Santos, T. 2002. |
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We studied the use of forest fragments by five medium-sized carnivore species in 280 forest fragments on the two Iberian plateaus.We looked for indirect evidence (faeces, tracks, dens) of fragment use (occurrence) by the species and analysed whether occurrence could be related to four groups of variables: local (vegetation structure and patch size), landscape (distance to possible colonisation sources), regional (fragment location on the northern or southern plateau) and the vegetation type of the fragments.We analysed the differential response of species according to their life-history and behavioural traits. The relationship between use by each species and the factors studied was analysed using stepwise logistic regressions. Results indicate that three factors are crucial to explain fragment use: fragment size, geographic location and vegetation type. Large fragments are used more than smaller ones, the northern plateau is more suitable than the southern plateau, and holm oak and broad-leaved oak forests are more used than pine woods. The effects and magnitude varied slightly among species, depending on habitat requirements or life-history traits. Data indicate that conservation strategies in fragmented environments must take into account elements functioning at different spatial scales, and that it is essential to consider each case within a characteristic regional context. |
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Virgos_et_al_2002_Response_to_forest_fragmentation_by_medium-sized_carnivores.pdf |
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Virgós, E., Cabezas-Díaz, S.,
Malo, A., Lozano, J., and López-Huertas, D. 2003. |
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This study analyses differences in European rabbit Oryctolagus cuniculus (Linnaeus, 1758) abundance between fragmented and continuous populations and the relative importance of habitat structure (micro- and macrohabitat) and isolation in determining the abundance pattern in fragmented and continuous areas of central Spain. The species was mainly restricted to mediterranean vegetation habitat. In fragmented areas, rabbit abundance was linked to scrubland cover hut was not correlated to pasture/cropland cover. The model explained very little of the observed variance. Distance to continuous populations did not improve the model. Stochastic phenomena or unmeasured factors (predation level, soil type) could be acting in this context. Rabbits were more abundant in continuous areas than in fragmented ones. In continuous areas, rabbit abundance was associated with mosaics of pastures, scrublands, and croplands. These habitat features are linked to shelter and feeding requirements of rabbits. The model explained an important part of the observed variance. This supports that management and conservation strategies should be based on the landscape pattern in each situation. |