Effects of social isolation and crowding on sexual behaviour in the rat (Rattus norregicus).

M.P. Viveros & R. Hernández
Dpto. de Biología Animal II (Fisiología Animal). Fac. de Biología. Univ. Complutense.
Ciudad Universitaria, 28040 Madrid.

Abstract. Effects of social isolation and crowding on sexual behaviour in the rat (Rattus norvegicus).- The effects of social isolation and crowding on the sexual behaviour of Sprague Dawley male and female rats (Rattus norvegicus) were investigated. The major housing condition effect was found among social isolates. A significant decrease in their non-copulatory activity was observed in both genders when compared with socially reared animals, but only a similar tendency appeared with respect to their copulatory activity. No clear effects of crowding on the animal's sexual behaviour was found. The importance of social experience during development for a complete sexual display in the adulthood is discussed. The absence of noticeable effects of crowding upon specific sexual patterns, and the influence of high population density upon several physiological systems are also discussed.

Key words: Rat, Social isolation, Crowding, Sexual behaviour.

A.F. Fraser
Fac. of Medicine, Health Sciences Centre, Memorial Univ. of Newfoundland, St. John's, Newfoundland, Canada, A1B 3V6

Abstract. Horse play as an ethosystem.- Forms of specific equine play can be seen as games in which behavioural laws (or rules) are employed. A great variety of play is the proyection into behaviour of a motivating force concerning action. The capability of the individual horse, as a mobile and social unit, depends on the developments which play facilitates. Horse play serves as a potentially useful model with which to compare analogous forms of play in other species. The resemblances with play in others are striking and could even provide material for appraising human play as an ethosystem which still functions.

Key words: Equine play, System of kinetic organization.

T.Redondo ¹, S.J. Hidalgo de Trucios ² & R. Medina ³
¹ Estación Biológica de Doñana, Pabellón del Perú, Avda. María Luisa s/n, 41013 Sevilla, Spain.
² Cátedra de Biología y Etología, Fae. de Veterinaria, UNEX, 10071 Caceres, Spain.
³ Dpto. de Biología Animal, (Sección de Zoología), Fac. de Ciencias, Univ. de Córdoba, 14004 Córdoba, Spain.

Abstract. Nest placement by azure-winged magpies (Cyanopica cyana).- Nest position inside the tree was studied in 32 nests of azure-winged magpies (Cyanopica cyana) belonging to three colonies. All nests were found in holm oaks (Quercus rotundifolia). Differences between colonies were observed regarding nest-tree size but not between variables characterizing the position of the nest. Nest height above ground did not correlate with tree size, while nest distance to bole did. It is argued that birds maximized nest-bole distance in order to prevent predation by nocturnal mammals. At a given nest-bole distance, nest position (nest-bole angle) inside the canopy is thus aimed at minimizing total costs arising from terrestrial predation, (which increased as nests were placed closer to the lowest branches) and those arising from aerial predation and poor nest insulation against climatic conditions (both of which decreased as nests were placed closer to lowest branches). At a given nest height, partial correlation analyses showed that nests placed at created distances from the bole survived for longer periods of time. Also, nest height affected nest survival adversely at a given distance to bole. Predictions of such a tradeoff model are supported: nests in trees with large canopy radii (and, hence, less prone to predation at given nest-bole angle) were placed in lower branches and survived better than comparable nests placed at wider angles. Data on nest site features for other populations are reviewed.

Key words: Cyanopica cyana, Nest site, Breeding ecology.

Uso del escudo anal por Gallinula chloropus en relación con el peligro por predación.

Abstract. The use of the rump patch by Gallinula chloropus in relation to predation.- Gallinula chloropus possesses a contrasting white rump patch which is shown by rapid tail raising. The rate of rump patch presentation per minute was higher when some raptor was flying over the subjects or when they were either vigilant or in a zone of greater danger of predation (on land rather than on deep water and distant from bullrush thickets). The rate of rump patch exhibition was also higher when the subjects were alone than when they were accompanied by other moorhens. In various aspects the visual alarm in moorhens follows the same rules as antipredator vigilance in other bird species. It is hypothesized that the frequency of tail raising is a signal to the possible predator of the performer's level of vigilance and hence of its predisposition to flee.

Key words: Gallinula chloropus, Rump patch, Predation.

M. Puigcerver ¹, J.D. Rodriguez-Teijeiro ¹ & S. Gallego ²
¹ Dpto. de Biología Animal, Fac. de Biología, Univ. de Barcelona, Avda. Diagonal 645, 08028 Barcelona.
² Museo de Zoología de la Fac. de Biología, Univ. de Barcelona, Avda. Diagonal 645, 08028 Barcelona.

Abstract. Migration and/or nomadism in the quail (Cotumix c. cotumix).- The census, modal moment of activity, and breeding of quails (Coturnix c. coturnix) at four sites in Catalonia between 1983 and 1988 were studied. The modal moment of activity at the southernmost site is related to the moment in which cereals approach the asymptote of their growth curve. A relationship was also found between the altitude of the sampling site and a) the modal moment of activity, b) the mean moment of hatching and c) the capture time of young birds. This relationship is explained in terms of cereal crop ripeness, which is delayed in high grounds compared to lower ones. These facts seem to point out to nomadic movements which may overlap with migration.

Key words: Coturnix, Movements, Migration, Nomadism.

N. B. Metcalfe
Dept. of Zoology, Univ. of Glasgow, Glasgow G12 8QQ, Scotland, UK.

Abstract. The effect of flocking on the efficiency of foraging search paths.- Previous studies have examined the searching efficiency of solitary foragers. There has also been much work on the cost and benefits of belonging to feeding flock. This study links the two lines of investigation, by examining how the search paths of feeding turnstones (Arenaria interpres) are influenced by the need to remain close to conspecifics. The results demonstrate that turnstones on the edges of a flock altered their search paths so as to move back towards conspecifics, but the strength of this tendency varies according to the benefits of flocking. Thus they are more likely to move towards conspecifics when the habitat reduces their ability to detect approaching predators, and less likely to do so when in mixed-species flock (when they can avoid conspecifics yet still remain within a flock).

Key words: Flocking, Foraging, Arenaria interpres, Shorebirds, Optimization.

Estudio comparado del juego materno-filial y paterno-filial en un grupo de gorilas (Gorilla gorilla gorilla) cautivos.

J.R. Gil & J.C. Gómez
Dpto. de Psicología Evolutiva, Univ. Autónoma de Madrid, 28049 Madrid.

Abstract. A comparative study of parent-infant play in a group of captive gorillas (Gorilla g.gorilla).- This paper reports a study of parent-infant play in a group of captive lowland gorillas (Gorilla g. gorilla). The group consisted of one adult male, one adult female and their offspring - a male infant aged 12-13 months. The results showed that, contrary to previous findings, both dyads played very frequently. Father-infant play was more active and intense and presented features of"rough-and-tumble", whereas mother-infant play was more relaxed and gentle, and slower, and occurred in longer episodes. Previous studies failed to find any significant play activities between infant and silverbacks and reported lower rates of mother-infant play. The high frequency of parent-infant play found in this study is ascribed to the minimal size of the group: both parents, but specially the father, would provide extensive social play interactions to compensate for the absence of appropriate peers in the group. The silverback's behavior is considered to be consistent with reports on their tolerance and behavioral flexibility towards infants.

Key words: Gorillas, Social Play, Father-Infant Interactions, Mother-Infants Interactions.

R. Campan & G. Beugnon
Centre de Recherche en Biologie du Comportement, U.R.A. CNRS n. 664 and Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cédex, France.

Abstract. Spatial memories and cognition in insects.- We first propose a classification of the different types of spatial memories observed during spatial orientation in insects: (1) The Read-Only-Memory is stored within the "hardware" of the animal; (2) The Volatile-Memory operates only during the current orientation process and is then reset to zero at the end of each excursion; (3) The Constant-Memory is stored by each individual according to its own experience. Two types of Constant-Memory orientation can be distinguished according to the way they are stored and used: as a file where discrete spatial information can be used in a standard succession and an unvariable sequence (Sequential-Access orientation memory) or as a file in wich the accesss to spatial information can be achieved from any known location (Random-Access orientation memory). At last, we discuss how these mnesic and cognitive processes could be involved during spatial orientation of insects in the complexity of their natural habitat.

Key words: Spatial memories, Spatial cognition, Insects, Homing, Field orientation.

The principle of self-reinforcement in nest building: evidence from abnormal nests of a weaverbird (Ploceus cucullatus).

N. E. Collias
Dept. of Biology, Univ. of California, Los Angeles, California 90024, U.S.A.

Abstract. The principle of self-reinforcement in nest building: evidence from abnormal nests of a weaverbird (Ploceus cucullatus).- The male african village weaverbird (Ploceus cucullatus) normally weaves a roofed nest with a bottom entrance to which he adds a short entrance tube after a female has accepted his nest. The young male must practice a good deal before he can make a normal nest, and each appropriate species-typical building act may be self-reinforcing (self-rewarding). Different kinds of abnormal nests observed over some years can be interpreted by and give evidence for this principle of self-reinforcement which enters into the selection and preparation of nest materials, general organization of the nest and sequence of nest stages. The importance of weaving from a fixed spot is emphasized. A male was induced to build an entrance tube several times the normal length and this habit persisted in subsequent years in absence of further training, suggesting that the male develops a mental image of what a completed nest should look like. Evidence is presented from a novel abnormal nest that some reasoning may possibly enter into the conception of his nest by an experienced male.

Key words: Nest building, Abnormal nests, African village weaverbird, Ploceus cucullatus, Self reinforcement, Self-rewarding act.

L. Flato, K. Houpt & C. Brozowski
Dept. of Physiology, N.Y. State College of Veterinary Medicine, Ithaca, N.Y. 14653-6401, USA.

Abstract. The behavior of feral donkeys (Equus asinus) in captivity.- The behaviour of captive feral donkeys was studied in order to compare their behavior with that of the free ranging donkey population studied by others. In addition to six feral donkeys, a donkey born by embryo transfer to a horse and a hinny (donkey dam and horse sire) were also observed. The time budget was: eating 51 %, resting while standing 8%, standing alert 27%, self grooming 2.5%, walking 6% and sniffing 2.5%. Other miscellaneous behaviors occupied 5% of the animal's time. This time budget was very similar to that of free ranging feral donkeys. The similarity between the behavior of captive and free ranging donkeys indicates that confinement is not particularly stressful to them. Drinking tended to occur more frequently in association with feeding than when the donkeys were not eating. There were some behaviors that occurred more frequently than what has been reported in free ranging females, such as braying (once per hour) and female-female. Urination tended to stimulate urination by other females.

Key words: Donkey, Behavior, Hinny, Feeding, Drinking, Vocalization.

X. Espadaler
Laboratorio de Zoología, Univ. Autónoma de Barcelona, 08193 Bellaterra, España.

Abstract. Ethology in spanish.- A list of ethological literature references in Spanish is provided. Whith the exception of the works by Darwin, Kohler and Fabre, the time elapsed between publication of the original text and the first Spanish translation ranged from l to 35 years (mean±SE=6.75±0.67), with a mode of 3 years. The potential of Spanish language to absorb and generate texts is emphasized.

Key words: Bibliography, Ethology, Spanish.