The capture of prey by the African lion in Ngorongoro Crater, Tanzania, is examined. For analytic purposes the process is envisaged as a consecutive set of events: searching, stalking, attacking, and subduing prey.Initiation of prey capture activity by the lion arises from the interaction of degree of stimulation presented by the prey, timing of the activity cycle of the lion (diurnal or nocturnal), and its level of hunger. These factors yield thresholds for initiation which result in kills being directly related to prey density at high and low densities and inversely density dependent at intermediate prey densities.Success in stalking appears to depend primarily upon the failure of the prey to see the approaching lion until it is within its effective distance. Using data from actual stalks and contrived experiments, the probability is calculated of the lion being detected for a range of conditions.The attack involves a matching of the sprinting abilities of the predator and prey. To analyze this aspect in detail, the velocity curves of running are defined for the lion and four prey species.

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The scent marking behaviour of coyotes, Canis latrans, was studied in Jasper National Park, Alberta, during the period 1974–1976. Results show that adult males and females scent mark throughout their territory at all times of the year. Urine is most frequently used in marking. The rate of scent marking at the edge of the territory is approximately twice that in the center. This increase is accomplished by reducing the distance between scent-mark sites and increasing the proportion of multiple marks. All members contribute to the marking behaviour of the pack, although the dominant male marks most frequently. The scent marks of neighbours at territory borders are not avoided but vigourously marked. Nevertheless, it appears that marking is associated with the maintenance of territory.

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The population size, area of occupation, and prey consumption of the resident prides of lions at Ngorongoro Crater, Tanzania, were studied from 1970 to 1972. Each pride of lions maintained a territory, yet this sometimes differed for the two sexes. The mean pride territory was 87.5 km2 corresponding to 5 km2 per lion.Net food consumption of an adult female was 2413 kg per year, of which about one-quarter was scavenged from prey killed by hyaenas. In contrast about one-quarter of the hyaena's food was scavenged from the lions' kills (a proportion involving forcing the lions to depart).The social organization of the lions in Ngorongoro Crater appears finely tuned to the extent that with a relatively stable food supply the population of lions remained stable with low input of young, no starvation losses of young during their period with the pride, but losses to the young age-classes resulting from aggression by adults. Aggressive interaction between prides primarily involved the males and seems not to be food related.