Companion animal management programs

Rowan, A. N., & Williams, J. (1987). The success of companion animal management programs: A review. Anthrozoos: A Multidisciplinary Journal of The Interactions of People & Animals, 1(2), 110-122.

In the early 1970s, a surge of interest in and attention to pet overpopulation led to a revamping of animal control programs around the country and to the promotion of an approach known as LES (legislation, education, sterilization). Concern about pet overpopulation and the killing of healthy animals in shelters continues to be high, but little is known about the effectiveness of LES over the past few years. The present paper reviews the available data and concludes that the pet overpopulation problem has improved in the last ten to fifteen years with only 10% of the national dog and cat population being euthanized in shelters today as compared to 20% in 1973. The data are insufficient to determine which of legislation, education, or enforcement has been the most important factor. Questions are, however, raised about the effectiveness of a sterilization program in the absence of good animal control.

Diet and home range of feral cats in Galápagos

Konecny, M. J. (1987). Home range and activity patterns of feral house cats in the Galapagos Islands. Oikos, 50: 17-23.

The spatial organization of two populations of feral house cats Felis catus, was examined in the Galápagos Islands using mark-recapture and radio telemetry. Both populations were located in the same habitat vegetation type and had approximately equal densities of cats. Two sites differing in resource density and habitat heterogeneity also differed significantly in home range size and amount of overlap. Male home ranges averaged 3.04 km² while those of females averaged 0.82 km². Monthly home ranges did not vary significantly. Activity patterns were roughly bimodal with peaks near dawn and dusk and lows near midday. Daily movement paths differed between sites. Resource levels and home range patterns suggest a resource threshold territoriality based on resource depression at the poorer site while no territoriality was found at the richer site demonstrating the adaptability and ecological flexibility of feral cats.

Konecny, M. J. (1987). Food habits and energetics of feral house cats in the Galápagos Islands. Oikos, 50: 24-32.

The food habits of feral cats (Felis catus) were assessed by visual observations and scats collected in two seasons and at two sites in the Galápagos Islands. Cats were seen to both scavenge and attack live prey with a capture efficiency of 32%. In seasonal comparisons significantly more food items were included in the dry season (7.4) than the wet (5.7). Significantly more items were included in the diet at Tagus Cove (7.8) which was less productive than Cerro Colorado (6.7). The diet included both vertebrate and invertebrate prey but vertebrates constituted 71.9% of each scat by weight and 93.4% of the energy. The estimated daily intake of energy was 170 kcal which is at the caloric break even point for non-pregnant females, slightly below that for adult males and pregnant females and well below that for lactating females. The food habit and energetic data were combined to make some predictions about food preferences, foraging decisions and the role of available water on feral cats.

Effects of FPL on a feral cat population

van Rensburg P.J.J., Skinner J. D. & van Aarde R. J. (1987) Effects of feline panleucopaenia on the population characteristics of feral cats on Marion Island. Journal of Applied Ecology, 24, 63-73.

(I) This paper evaluates the effects ofthe artificial introduction offcline panleucopaenia (FPL) as a primary control measure ofa feral cat population on the sub-Antarctic Marion Island (46º54'S,37º45'E). 

(2) The population decreased from an estimated 3409 cats in 1977 (introduction of control factor) to 615 (S.E. = 107) cats during 1982, suggesting an annual rate of decrease of 29%. 

(3) Litter size decreased and the age structure changed significantly because ofa decrease in subadult numbers. Age specific mortality rates were higher but followed the same pattern as in 1975 because there were fewer subadults but the same age structure of adults. 

(4) The intrinsic rate ofincrease, as suggested by the survival and fecundity schedules of the: population, was higher in 1975 owing to a greater proportion of adults and a higher fecundity in age class II. 

(5) Antibody titres of FPL were lower in 1982 than in 1978 which illustrates that FPL did affect the cat population but is no longer spreading effectively. FPL was independent of feline herpes (FVR), an endemic disease of the cat population. and FPL was, therefore, directly responsible for the decrease in cat population density. 

(6) During 1982 the cat population showed a decrease of 8% year-I, whieh indicates stabilizing of the negative growth rate. This observation was supported by lower titres of FPL. 

Predation by domestic cat in a British village

Churcher , P.B. & J.H. Lawton. 1987. Predation by domestic cats in an English (UK) village. Journal of Zoology. (London.) 212: 439-455

We studied predation by approximately 70 domestic cats (Felis catus L.) in the Bedfordshire village of Felmersham over a one-year period. All the prey items brought home by virtually all the cats in the village were recorded and, where possible, identified. A total of 1090 prey items (53i5 mammals, 297 birds and 258 unidentified animals) were taken, an average of about 14 per cat per year. Twenty two species of birds and 15 species of mammals were identified. The most important items were woodmice (17%), house sparrows (16%) and bank voles (14%).

Old cats of both sexes caught fewer prey over the year than young cats. Female cats on the edge of the village also caught more prey than female cats in intermediate or central areas of the village; male cats showed no such effect. The type of prey caught also varied with position in the village; ‘core’ cats caught proportionately more birds than ‘edge’ cats. There was some indication in the data that cats caught fewer prey in areas where cat density was highest, but this effect was impossible to disentangle from position in the village. Weather apparently influenced hunting success. Temperature had no direct influence, but fewer prey were caught in winter; cats also caught less on wet days and windy days.

Estimates of the number of house sparrows in the village at the start of the breeding season, and the number of sparrows known to have been caught by the cats, suggest that at least 30% of the sparrow deaths in the village were due to cats. Domestic cats would appear to be major predators in this typical English village.