A radio-tracking study of two adjacent social groups of red foxes was conducted in a suburban residential district of greater Toronto from late July through December 1990. This was the ®rst radio-tracking study of red foxes living completely within a large metropolitan centre in North America. The groups had nonoverlapping home ranges and included both breeding and non-breeding adult females. Mean group home range size was 52 ha, toward the small end of home ranges documented for the species, and distances travelled nightly by adults of both sexes ranged from 2±20 km. The home ranges of both groups were primarily located in a bushy ravine containing golf courses and park land, but individual foxes readily utilized areas of low-density housing characterized by large, well-vegetated lots. However, the foxes avoided adjacent medium-density housing areas, indicating that this population may not be as habituated to urban life as some populations described from Great Britain and mainland Europe. Because of their constant proximity to, and frequent use of, some residential habitat types, these foxes have ample opportunity to transmit diseases such as rabies to domestic pets and humans in the vicinity.
Home ranges, spatial movements and patterns of habitat use were determined during a radio-tracking study on four male and six female Philippine tarsier Tarsius syrichta in Corella, Bohol, from early March to October 1999. This was the ®rst radio-tracking study of the Philippine tarsier that included both breeding adult males and females. Home ranges averaged 6.45 ha for males and 2.45 ha for females (MCP and Kernel 95%), allowing for a density of 16 male and 41 female tarsiers per 100 ha. The habitats are primarily located in secondary lowland rainforest in early to mid succession stage, but individual tarsiers readily traversed open grass areas to move between forest patches. However, the tarsiers avoided adjacent residential areas, clearings and agricultural plantation, even if the last two were found enclosed in homerange polygons. The home range of one male overlapped extensively with that of one female and to a lesser extent with a second female. Home ranges of males showed little overlap (2.71%) and the same was observed among the females (3.35%). Nightly travel distance averaged 1636 m for males and 1119 m for females. Individuals were observed to forage and sleep solitarily. The tarsiers form groups of one adult male and one or two adult females and their offspring.
The European hare Lepus europaeus and the European rabbit Oryctolagus cuniculus are sympatric in many areas of the world. They are medium-sized herbage-feeding lagomorphs and trophic competitors. Both species feed on twigs under extreme and perhaps limiting conditions. To ascertain whether fine niche separation mechanisms occur, several comparative tests of digestive function were undertaken on samples of animals drawn from sympatric populations. The weights of the organs constituting the abdominal alimentary canal, the rates of passage and the extent of trituration of dietary markers intended to mimic twigs, and the digestibility of fibre, protein, and fat were compared. Both the stomach and the caecum of the hare were significantly smaller as a proportion of body weight, and this would result in a higher power-weight ratio. Both species rapidly passed the digestive marker, but passage was significantly faster in the hare. The rabbit chewed twig-like material with a scissor cutting and crushing action, whereas the action of the hare included a stripping action that would more efficiently access soluble carbohydrates stored in vascular rays. Both species were poor digesters of fibre, but digestibility of hemicelluloses was significantly greater in the rabbit. The faeces of both species of lagomorphs contain nutrients that can be attractive to more efficient fermenters of plant fibre, and consumption of those faeces may confound lagomorph population surveys that rely on dung counts.
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