Time and Space Use by Two Common Genets (Genetta genetta) in the Donana National Park, Spain

Abstract

Viverrids have not been studied in the same detail as other families of carnivores (Eisenberg, 1981). For common genets, Genetta genetta, references to its use of space and time are anecdotal, scarce, and usually included in papers on more general topics. Some studies undertaken in Africa on behavior of free-living Genetta genetta (Ikeda et al., 1983; Waser, 1980) must be attributed to Genetta felina after the taxonomic revision of the genus by Schlawe (1980). In this paper, we present information on patterns of activity, homerange size, habitat use, and daily movements of two common genets radio-tracked between September 1985 and April 1986. The study was conducted at the Doniana National Park, which occupies 550 km2 on the right bank of the mouth of the River Guadalquivir, in SW Spain (ca. 37*N, 630'W). It includes three main biotopes: the marshes or marismas, the scrubland, and the dunes. Usually the marshes are flooded in winter, and they were not used by the genets during this study. There are two main types of scrubland: a dry, xerophytic scrubland vegetated by Halimium sp. and Rosmarinus sp. that reach a height of 1.2 m and with relatively low ground cover, and a dense, mesic scrubland vegetated by Erica sp. and Calluna vulgaris, that may reach 3 m in height and cover the ground completely. In the dunes, there are mobile bare sand dunes and depressions or valleys in between, usually colonized by pine (Pinus pinea) forests. Climate is mediterranean subhumid, characterized by dry, hot summers and mild, wet winters. We radio-tracked a young female (weight, 1,040 g; deciduous dentition) and an adult male (weight, 1,750 g; teeth showing no wear signs). Both were captured in live traps baited with sardines, immobilized by injection of a mixture of ketamine hydrochloride (ketolar) and tiazine hydrochloride (Rompun) and equipped with radio-collars (Wildlife Materials Inc.) with switch sensors. The signal was received by a portable AVM LA-12 receiver. The locations were determined by triangulation from a vehicle. We located the genets at least once an hour during seven 24-h periods, and 155 times at random hours of the day apart from intensive tracking periods. A total of 330 locations was determined. Home-range shape and size were estimated from the independent locations, using the smallest convexpolygon method (Macdonald et al., 1980). To determine the zones of most intense use we represented the utilization distribution (Van Winkle et al., 1973) on 10,000-m2 squares. To estimate hourly activity we used distances traveled at each hourly interval of the 24-h tracking periods. The switch sensor of the radio-collar allowed us to know if the animal was active during independent locations. The daily movements were estimated by adding straight-line distances between 25 consecutive hourly locations and multiplying the results by 1.46, an empirical value obtained by Palomares (1986) while tracking the Egyptian mongoose (Herpestes ichneumon) in the same area. The activity of the adult male was exclusively nocturnal, as is usual in genets (Diicker, 1965; Waser, 1980). None of the 70 locations obtained during daylight hours revealed activity. Nevertheless, the young female was active in 19% of 62 locations made during daylight hours, the percentage increasing to 65% (n = 51) during the night. Previously, Ikeda et al. (1982) reported diurnal activity for a female Genetta tigrina in Ethiopia. The partially diurnal activity of the young female we tracked may be explained by its age, as observations of captive genets by one of us (MD) suggest that nocturnality predominates as animals mature. Also, the animal lived exclusively in a dense heather scrubland, where high concealment could diminish interference competition with larger predators, allowing a relaxation of its schedule of activity. Both genets showed greater activity from sunset to midnight, with a secondary peak of activity by the male just before sunrise (Fig. 1). The home range of the young female from 26 September to 31 December was 1.4 km2. On a monthly basis, however, home-range size was 0.2 km2 in October, 0.7 km2 in November and 1.2 km2 in December,with the number of locations roughly similar for the three months (37, 38, and 47, respectively). These results suggest that the female, probably born in the zone, was increasing its familiar environment, as described by Rowe-Rowe (1970) from a young Genetta rubiginosa kept in captivity.