Wagner, G. (1975). [Flight leadership in flocks of homing pigeons]. Z. Tierpsychol., (39), 61–74.
Abstract: Groups of 3-5 homing pigeons individually recognizable by different colours of their plumage were followed by helicopter on their way home. In most cases the animals flew together as a group with frequently changing leadership. Flight formations in terms of leadership were noted every minute. It was examined statistically whether the flight order varies at random or whether there are leading and led birds. In 6 out of 7 experiments with groups of 4-5 pigeons flight order was far from random, one or two pigeons proving to be leaders. In only one experiment leadership did not differ from a random distribution. No correlation could be found between the tendency to lead within a group and homing performance of the single pigeon when released individually.
|
Syme, G. J., & Syme, L. A. (1975). The concept of spatial leadership in farm animals: An experiment with sheep. Anim. Behav., 23(Part 4), 921–925.
Abstract: The concept of spatial leadership as applied to farm animals is discussed with particular emphasis on methodological problems. Using three experimental procedures forced spatial leadership orders were measured in a group of Romney ewes. Comparisons between orders showed the effects of both the different experimental tasks and the social context on leadership structure. Both these variables were found to affect the orders obtained. The results are interpreted in terms of the utility of the concept of spatial leadership in domestic animals and the necessity for more systematic procedural investigations in this area.
|
Feist, J. D., & McCullough, D. R. (1975). Reproduction in feral horses. J Reprod Fertil Suppl, (23), 13–18.
Abstract: A behavioural study of feral horses was conducted on the Pryor Mountain Wild Horse Range in the western United States. All 270 horses on the Range were identified individually. The sex ratio was nearly balanced. Foal to adult female ratio was 43-2:100. Morality was concentrated among foals and old horses. Horses were organized as forty-four harem groups each with a dominant stallion, one to two immature stallions, one to three immature mares, one to three adult mares and their yearling and foal offspring, and 23 bachelor groups of one to eight stallions. Harem groups were quite stable year-round because of dominance and leadership by the stallions and group fidelity by mares and their offsring. Most changes occurred during the breeding season and involved immature females. Defeat of dominant stallions was infrequent. Immature males were tolerated because of their submissive behaviour. Bachelor stallion groups were inherently unstable. Mares came into heat after foaling in May/June, and were mated by harem stallions only.
|
Western D,. (1975). Water availability and its influence on the structure and dynamics of a savannah large mammal community. E Afr Wildl J 1, 3, 265–288.
|
Welsh Da,. (1975). Population, behavioural, and grazing ecology of the Sable Island, Nova Scotia. Ph.D. thesis, Dalhousie University, Halifax.
|
Smuts Gl,. (1975). Pre – and postnatal growth phenomena of Burchell's Zebra, Equus Burchelli Antiquorum. Koedoe, 18, 69–102.
|
Smuts Gl,. (1975). Home range sizes for Burchell's Zebra, Equus burchelli antiquorum from the Krüger National Park. Koedoe, 18, 139–146.
|
Short Rv,. (1975). The evolution of the horse. J Reprod Fert Suppl, 23, 1–6.
|
Ruckebusch Y,. (1975). The hypnogram as an index of adaptation of farm animals to changes in their environment. App Anim Ethol, 2, 3–18.
|
Rossdale Pd,. (1975). Das Pferd, Fortpflanzung und Entwicklung. Karger 1975, .
|