Heavy flooding effects on home range and habitat selection of free-ranging Iberian hares (Lepus granatensis) in Doñana National Park (SW Spain)

The Iberian hare Lepus granatensis is a common and abundant species throughout the Iberian Peninsula; however, studies documenting its ecology are scarce. Between August 1996 and September 1997, after a long drought, we studied the effects of a widespread flood on the Iberian hare ecology in ecotone pastures of Doñana National Park. Hares were captured using vertical nets through part of 1996 and 1997. Fourteen adult hares (nine females and five males) were tagged with radiocollars and located by triangulation on a daily basis at least once a week. Habitat use was estimated using a geographical information system. The average home range size was 28 ha for males and 24 ha for females. No significant differences were observed between sexes. Significant differences were observed in the use of scrub areas and in dry pastures. During the dry and wet seasons, males and females were most often located in the pastures of the ecotone, rush stands and scrub. The dense bracken (Pteridium aquilinum) and seaside bulrush (Scirpus maritimus) communities were avoided. These results are the first on the spatial ecology of this species in its native habitat.Plan Andaluz de Investigación. Junta de Andalucía. RNM-118Comisión Interministerial de Ciencia y Tecnología de España. Proyecto “Efecto de las inundaciones en poblaciones de liebres en el pantano de Doñana". CICYT (1996-1997

Survival of mediterranean hare (Lepus granatensis Rosenhauert, 1856) in Doñana National Park during a wet year

Desde agosto de 1996 hasta septiembre de 1997, coincidiendo con una época de fuerte inundación invernal, se han estudiado los patrones de supervivencia (mediante marcaje individual en las orejas y por radioemisores) de la liebre ibérica (Lepus granatensis Rosenhauer, 1856) en dos zonas, Marisma-Veta y Vera, del Parque Nacional de Doñana con diferentes características botánicas y fisiográficas. Además, durante las inundaciones una zona tenía posibilidades de migración (Vera) y la otra no. También se analiza la supervivencia en función del sexo. Sólo se han considerado los individuos adultos. Aplicando el test de Kaplan-Meier se ha establecido, para el citado periodo, una supervivencia del 38% para un periodo de 141 días en la Marisma y 22% para un periodo de 244 días en la Vera. No se han encontrado diferencias significativas mediante el test de Mantel-Cox. La supervivencia por sexos varia del 29% en machos al 26% en hembras, sin apreciarse tampoco diferencias significativas. Se discuten estos resultados y se comparan con otras especies de liebres.A total of 29 hares (14 in the marshland and 15 in the ecotone zone) were tagged and marked with radiocollar during the summer of 1996. The periodic study finish in September 1997. An unusually hight rainfall, during the fall of 1996, produced a long winter flooding of the lowland. The estimated survival of the hares (following the Kaplan-Meier method) for the periodic study was 38% (marshland) for a period of 141 days and 22% (ecotone) for a period of 220 days. No significant differences were observed (Mantel-Cox test). By sex, the survival was variable (29,17% for males and 26,61% for females). No significant differences were observed. The low survival rate observed in this study was compared with another hare species and habitats.Programa Sectorial de Promoción General del Conocimiento (DGICYT), Ministerio de Educación y Ciencia de España APC96-0075Junta de Andalucía. Grupo RNM 011

Abundance trends of the Iberian hare (Lepus granatensis Rosenhauert, 1856) in Doñana National Park

Se ha estudiado la evolución numérica de las liebres en el Parque Nacional de Doñana mediante el índice kilométrico de abundancia (IKA) durante los años 1995, 96, 97 y 98, aplicando un muestreo estratificado por grandes unidades de vegetación. Los medios prospectados han sido: Vera, Marisma baja, Marisma de transición y Marisma alta. El periodo de inicio del estudio se caracterizó por una fuerte inundación, la más importante en los últimos 26 años y el último año se ha caracterizado por una fuerte sequía. En total se recorrieron 294,9 km y se censaron 306 liebres, con un Ika global de 1,04 liebres/km. Entre años y hábitat, las diferencias entre los Ikas son significativas (test de Friedman = 7,8 (gl = 3 p<0, 05). Finalmente, se discuten los resultados y se propone un modelo de regulación poblacional para el Parque Nacional de Doñana.The density and relative abundance index (IKA: hares/km) of the Iberian hare (Lepus granatensis) was studied in Doñana National Park (DNP) in 1995, 1996, 1997 and 1998 in the main 4 plant communities of DNP (ecotone zone –Vera-, lowland marshland, highland marshland and transition low-high marshland). During the 4 year study period there has been an alternate cycle of drought and flooding. The first study year (1995) was the last one of a long (5 year) drought period (1991-1995). 1996 and 1997 were very wet (the wettest in the last 26 years). In 1998 a new drought period started again. A total of 294,9 km were census and 306 hares were counted. The global observed Ika was 1,04 hares/km. Significant differences were observed in IKA between years and plant communities. After a high abundance index period (1995) a high intensity marshland flooding in 1996 and 1997 produce a fast decline in the hare population density. During the following years a recolonization process was observed. Finally, a regulation model for the hares is proposed an the results are discussed according the proposal hypothesis.Programa Sectorial de Promoción General del Conocimiento (DGICYT), Ministerio de Educación y Ciencia de España APC96-0075Junta de Andalucía. Grupo RNM 011

Diseases of Iberian ibex (Capra pyrenaica)

Iberian ibex (Capra pyrenaica) is an ecologically and economically relevant medium-sized emblematic mountain ungulate. Diseases participate in the population dynamics of the species as a regulating agent, but can also threaten the conservation and viability of vulnerable population units. Moreover, Iberian ibex can also be a carrier or even a reservoir of pathogens shared with domestic animals and/or humans, being therefore a concern for livestock and public health. The objective of this review is to compile the currently available knowledge on (1) diseases of Iberian ibex, presented according to their relevance on the health and demography of free-ranging populations; (2) diseases subjected to heath surveillance plans; (3) other diseases reported in the species; and (4) diseases with particular relevance in captive Iberian ibex populations. The systematic review of all the information on diseases affecting the species unveils unpublished reports, scientific communications in meetings, and scientific articles, allowing the first comprehensive compilation of Iberian ibex diseases. This review identifies the gaps in knowledge regarding pathogenesis, immune response, diagnostic methods, treatment, and management of diseases in Iberian ibex, providing a base for future research. Moreover, this challenges wildlife and livestock disease and wildlife population managers to assess the priorities and policies currently implemented in Iberian ibex health surveillance and monitoring and disease management

Body Parameters and Growth of the Wild Rabbit, Oryctolagus cuniculus (L.), in Western Andalusia

Se han medido las longitudes totales, radio-cúbito, pie, tarso y oreja así como el peso de 520 conejos. Se han analizado los posibles pares de interrelaciones de estos seis parámetros corporales. Las ecuaciones de las rectas de regresión que mejor se le ajustan se han resumido en el cuadro 2. También se ha analizado la relación peso-edad real de los conejos, ajustándosele a la nube de puntos las funciones de Gompertz y Logística (Fig. 1a y b). Se dan los coeficientes de ambas funciones que minimizan los residuos. Se discuten los diferentes ajustes y se establece que las acuaciones que se obtienen (lineales o no) son un método aceptable para conocer un parámetro corporal a partir de cualquiera de los otros. También es válido para conocer la edad de los conejos. por lo que se sugiere su empleo en los estudios de selección de presa por los predadores.Five different morphological measurements and the weight of 520 rabbits have been taken. All possible pairs of interelationship of these six body parameters are analysed. The equations of regresion lines that best fit are summarized (Table 2). The age-weight relationship of rabbits is also analysed, the Logistic and Gompertz curves fitting the data. The coefficients of both functions which minimized the residues are given. The different fits are discussed. The equations obtained are a useful method to find out a body parameter from any of the others. It is also used to find out the age of rabbits and hence its use is indicated in the studies of prey selection of rabbit predators

Sex ratio and age structure of a Mediterranean wild rabbit (Oryctalogus cuniculus L.) population in Western Andalusia (Spain)

Se ha estudiado durante 24 meses consecutivos una población de conejos (Oryctolagus cuniculus) en un hábitat típicamente mediterráneo del S.O de España. Los conejos, capturados vivos con la ayuda del hurón y de redes se marcaron, pesaron, midieron y se le anotó el sexo. El presente trabajo aporta datos inéditos sobre dos aspectos concretos de la dinámica de población de esta especie: la estructura de sexos y edades. La razón de sexos (RS=N.º hembras/N.º toral de capturas) favorece a las hembras (RS=0,63). Se ha observado también que RS es más alto en las clases de edad adulta. Asimismo se ha puesto de manifiesto una evolución estacional en RS, con valores muy altos en los meses de invierno y primavera. Se discuten las posibles estrategias por las que se puede presentar esta diferencia con la RS esperada (0,5) y se sugiere que una diferencia de comportamiento entre ambos sexos (por el que los machos pasan más tiempo de su vida en la superficie) junto con una elevada presión de predación, serían los responsables de los altos valores de RS en las poblaciones de conejos en la zona mediterránea ibérica. En cuanto a la estructura de edades, se ha observado que sigue un patrón cíclico, estrechamente relacionado con la actividad reproductiva de los conejos. Se sugiere también su simplificación a sólo dos modelos de estructura de edades que se corresponden con los periodos de actividad e inactividad reproductiva. Se discuten las ventajas e inconvenientes de esta simplificación.Sex ratio (RS) and age structure of a Mediterranean wild rabbit (Oryctolagus cuniculus) population have been studied in a northwestern Andalusian (Spain) locality from January 1976 to December 1977. Rabbits were caught alive using a ferret and nets, and their sex and body weight determined. It was observed that RS was significantly blased in favour of females (average RS=0,63). RS was greatest among the adult age classes. The analysis of the monthly evolution of RS showed that the highest values of the RS coincide with the main reproductive season of the rabbit population, suggesting that the peculiar behaviour of the male rabbit (spending more time outside the warren defending its territory) may be the cause of the high RS values. In addition, the high predation pressure faced by rabbits in the Iberian Mediterranean habitat may similarly be related to high RS figures. Age structure shows a destined seasonal pattern and it is related to temporal variations in reproductive activity of the population. Two simple models of age structure are proposed for better understanding the population dynamics of the rabbit, and the advantages and disadvantages of each of them are stressed

Composition of the Passerine Bird Communities in two Southern Spanish Habitats

The composition of the passerine bird communities inhabiting two southern Spanish habitats was investigated from October to June. The habitats were a "Matorral" stand composed of many scrub species, and a Quercus woodland in which were represented several oak species together with a dense, varied understory ("Umbría"). Linear transects were conducted and the results are given as relative frequencies of occurrence of the various species per unit of length walked. Seasonal changes in total number of contacts, number of species and the ratio contacts/species are obtained for both plots. The relative importance of resident species with respect to number of contacts is rather high in both sites throughout the study period, and larger in the Umbría site than in the Matorral. The significance of this high importance of individuals belonging to resident species is discussed in the light of previous studies and it is concluded that this appears to be a common feature to all southern Spanish mediterranean bird communities so far studied, regardless of the habitat type involved.Se ofrecen los resultados de una investigación dirigida a determinar la composición de dos comunidades de passeriformes en dos biotopos de Sierra Morena occidental, en el norte de la provincia de Sevilla. Una extensión de monte bajo ("Matorral") y un encinar-alcornocal-quejigal ("Umbría") fueron recorridos mensualmente desde Octubre a Junio. Los resultados se expresan como frecuencias relativas de contactos para cada especie y se estudia la evolución estacional de varios parámetros que describen globalmente la comunidad (número de especies, número total de contactos por unidad de longitud y el cociente de dividir esta última cifra por la primera). Las dos comunidades estudiadas se caracterizan por poseer una elevada proporción de individuos pertenecientes a especies residentes a lo largo de todo el período de estudio. Esta parece ser una peculiaridad propia a todos los hábitats mediterráneos del sur de España estudiados hasta la fecha

Morphology and sexual dimorphism in the pelvis of Pitymys duodecimcostatus

The pelvis of 87 specimens (39 females and 48 males) of Pitymys duodecimcostatus were examined to find morphological and biometrical features allowing the identification and sex determination of remains found in owl pellets. The results obtained were tested by applying them to a sample of 62 pelvis from Barn OwI pellets. Species determination was easily done in all instances since shape of pelvis of Pitymys (figura 1) is quite distinct from those of other coexisting rodent species (mostIy Muridae). On the basis of mensural criteria, sex determination was achieved for the 87,1% of the pelvis in the sample, then the criteria obtained appear to be reliable