Social organization and space use in the Cape porcupine in a Southern African savanna

Abstract

SummarySix male and four female adult Cape porcupines (Hystrix africaeaustralis) were radiotracked between July 1989 and June 1990 in a southern African savanna in order to investigate their social organization and space-use patterns. They lived in family groups based upon monogamous adult pairs. Pair members shared burrows and home range areas and all pairs were stable for the duration of the study. It is suggested that the occurrence offamily groups is largely dependent on the opportunities available for mature offspring to disperse from their natal group. Individual home ranges occupied the same general location throughout the year although the exact area used varied from month to month and most activity was concentrated in a relatively small portion of a potentially larger area. Natural foragers had significantly larger home ranges in winter than in summer. Crop foragers exhibited no significant seasonal difference in range size.Home range overlap between natural foraging neighbours was greatest in winter but even then was not extensive, there being little overlap between neighbouring 95'/"0 and 90% home ranges. It is therefore suggested that porcupines are territorial, maintaining a small, exclusive territory within a larger, non-exclusive home range. Neighbours rarely encountered one another in the areas of overlap and territories were probably maintained by scent marking rather than through direct interactions. :2 N. U Corbet and R. J. Van ;tarde nourrissaient en nature disposaiellt (rLll1 territoire significativement plus vaste en hiver qu'en ete alors que ceux qui se nourrissaient sur les cultures ne presentaient pas de difference significative dans ce domaine.Le recouvrement des espaces vitaux des animaux qui se nourrissaient en nature ctait plus important en hiver qu'en ete, mais meme alors il n'etait pas tres grand, car il y avait peu de recouvrement entre 90 a 95(% des espaces vitaux avoisinants. C'est pourquoi on suggere que les porcs-epics sont territoriaux, et conservent un petit territoire exclusifinclus dans un espace vital plus etendu mais non exclusif. Les voisins se rencontrent rarement dans les endroits de recouvre ment, ct les territoires sont probablement gardes au moyen de marques olfactives plutoL que par des interactions directes.

Use of space and movement patterns in monogamous adult Eurasian beavers (Castor fiber)

“…Blanford's fox V. cana, Geffen & Macdonald, 1992; mahogany glider Petaurus gracilis, Jackson, 2000;rock-haunting possum P. dahli, Runcie, 2000). The male-female territory overlap of 81% found in this study is in line with territory overlaps among paired adults from other monogamous mammal species (Cape porcupine Hystrix africaeaustralis: 75%, Corbet & Van Aarde, 1996; mahogany glider P. gracilis: 85.9%, Jackson, 2000; Blanford's fox: 79.9%, Geffen & Macdonald, 1992). Furthermore, minimal intra-and intersex overlaps between residents and neighbours are generally seen as a good indication for strong territorial behaviour of both sexes (Marinelli & Messier, 1993;Powell, 2000).…”

Using Patch Focals to Study Unhabituated Dry-Habitat Chimpanzees (Pan troglodytes schweinfurthii) and Sympatric Fauna at Issa, Ugalla, Tanzania

“…The use of more open woodland habitat is reflective of the encounters of hyraxes and hares, while other animals, such as genets and pangolins, were most often seen in forest, as would be expected based on their general habitat preferences at other sites (Estes 1991;Kingdon 1997;Martinoli et al 2006;Skinner and Chimimba 2005). Finally, the disparity in habitat use by rodents can be explained by the large number of encounters of squirrels and porcupines, animals that more often use woodland habitats as compared to forest (Corbet and Aarde 1996;Emmons 1980;Estes 1991;Kingdon 1997de Villiers and van Aarde 1994).…”

Habitat richness affects home range size in a monogamous large rodent

“…Seasonal variation in food availability could have forced natural foragers (sites A and D) to display a spatial behaviour known as "seasonal contraction" i.e. increased HR size when resources are dispersed/far from the den, and decreased HR size when resources are concentrated/close to the den (Kruuk and Macdonald, 1985;Corbet and Van Aarde, 1996). In other studies (Saltz and Alkon, 1989;Corbet, 1991), crop foragers lived in dens near cultivations, but in our study area (sites A and D), cultivated fields were located in sandy areas, unsuitable for denning (Corsini et al, 1995;Monetti et al, 2005).…”

“…male and female of 8 pairs were radio-tagged, whereas the mates of the remaining individuals had radio-tags on, but they were not included in this study because of premature tag failure. As there were 8 pairs of porcupines in our radiotracked sample and pair members tend to move together (Sever and Mendelssohn, 1991;Corbet and Van Aarde, 1996), relevant data on HR size could be pair-autocorrelated. Then, we cross-analysed our data by sex, including also the porcupines whose mates wore non-functioning radio-tags.…”

“…Burgman and Fox, 2003) have been mitigated (cf. Saltz and Alkon, 1989;Corbet and Van Aarde, 1996) by discarding the peripheral 5% of fixes, i.e. the extreme locations.…”