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Mal, M. E., McCall, C. A., Newland, C., & Cummins, K. A. (1993). Evaluation of a one-trial learning apparatus to test learning ability in weanling horses. Appl. Anim. Behav. Sci., 35(4), 305–311.
Abstract: Fourteen Arabian foals were used to determine if a one-trial appetitive conditioning task, developed for laboratory rats, could be adapted for use in equine learning research. The learning apparatus consisted of a 1.5 m x 0.6 m wooden grid containing 40 compartments. Seven foals received a complete learning test which consisted of placing a foal in a pen with the learning apparatus on one wall, recording the foal's behavior for 5 min and then placing a food reinforcer in a target compartment (TC). After location of the food, the foal's behavior was recorded for an additional 5 min. Total visits made to the apparatus and compartments visited by the foal were recorded. The remaining seven foals received a test in which no reinforcer was placed in the TC. These foals were re-tested the next day with reinforcement. After location of the food reinforcer, all foals exhibited more visits to the apparatus, visits to the TC, visits one compartment from the TC, and visits greater than one and less than or equal to two compartments from the TC (P<0.05). Mean distance of visits from the TC decreased after location of the reinforcer (P<0.05). Increased frequency of visits to the apparatus and concentration of visits around the TC after finding the reinforcer suggest that foals had learned the location of the reinforcer. Results suggest that a one-trial appetitive conditioning test may be applicable in equine learning research.
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Boyd, L., & Bandi, N. (2002). Reintroduction of takhi, Equus ferus przewalskii, to Hustai National Park, Mongolia: time budget and synchrony of activity pre- and post-release. Appl. Anim. Behav. Sci., 78(2-4), 87–102.
Abstract: A harem of takhi (Equus ferus przewalskii) was observed during introduction to the Hustain Nuruu Steppe Reserve of Mongolia. The goals were to examine whether the harem exhibited significant behavioural synchrony, whether release had an effect on time budget, and what the implications might be regarding acclimatisation to the wild. Behaviours were scan sampled every 10 min between the hours of 06:00 and 22:00, twice before release, twice immediately after release, and twice 2 years after reintroduction. Time budgets were constructed from these data. Considerable behavioural synchrony was evidenced both before and after release. Crepuscular grazing and midday resting were typical, regardless of the date relative to release. Upon release, the amount of time spent moving doubled for all age classes. It is suggested that this increase resulted from exploration. The amount of time spent grazing and standing remained unchanged; the increased amount of time spent moving came at the expense of resting. Two years later, the horses still spent more time moving than when captive. Somewhat less time was spent grazing, although the difference was not significant. More time was spent resting in 1996 than immediately after release. These time budgets provide evidence of successful acclimatisation to the wild. Trekking between favoured sites could account for the persistent increase in time spent moving, with concomitantly less time needed to meet nutritional needs by grazing and more time available for resting. Housing captive takhi in large enclosures is evidently insufficient to permit the amount of movement exhibited by this wild harem. The time budget of the 1- and 2-year olds was more similar to that of adults than foals, indicating approaching adulthood. That 1- and 2-year olds were nursed, without loss of body condition by the dam, provided additional evidence that the takhi achieved excellent nutritional status in the wild.
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Pavey, C. R., & Smyth, A. K. (1998). Effects of avian mobbing on roost use and diet of powerful owls,Ninox strenua. Anim. Behav., 55(2), 313–318.
Abstract: We observed the species and numbers of mobbing birds and their effects on a large, nocturnal, bird-eating predator, the powerful owl, together with the pattern of owl predation on mobbing and non-mobbing species. Owls were mobbed on 35 occasions by seven of 44 species of forest birds at a site composed of open forest (88% by area) and rainforest (12%). The majority of bouts involved individuals of a single species, although mixed groups were observed on nine occasions. Regular mobbers were between 4 and 26% of the owls' body weight. Owls abandoned their daytime roosts during 20% of bouts and responded by calling or actively monitoring mobbers during 54% of bouts. Mobbing appeared to explain why owls roosted in rainforest significantly more often than expected by its availability, mobbing being significantly less frequent in rainforest than in open forest. Only one mobbing species regularly occupied rainforest and the canopy of roosts in rainforest was denser than that in open forest, thus reducing the chances of an owl being detected by potential mobbers. Twelve species of forest birds were within the range of prey size of the powerful owl (75-800 g): six were mobbers and six non-mobbers. The frequency of owl predation on non-mobbers was 8.75 times that on mobbers. The species in this study took a high risk by mobbing a very large predator, but benefited by greatly reducing their chances of predation.
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Pettifor, R. A. (1990). The effects of avian mobbing on a potential predator, the European kestrel, Falco tinnunculus. Anim. Behav., 39(5), 821–827.
Abstract: European kestrels were observed being mobbed by other birds on 63 occasions. Eleven species were involved, and in two instances mobs were composed of more than one species. Both flight-hunting and perch-hunting kestrels flew significantly further between their foraging positions when they were mobbed than when they were not mobbed; on average, mobbing resulted in flight-hunting kestrels moving 6[middle dot]8 times, and perch-hunting kestrels 2[middle dot]7 times, the mean distances moved by non-mobbed birds. The mean strike distance of perch-hunting kestrels attempting to capture birds was significantly less than the distance between perches flown by perch-hunting kestrels when mobbed. These data provide quantitative support for the assumption that mobbing causes a predator to vacate its immediate foraging area. The activity of the kestrels also influenced the frequency that they were mobbed, with kestrels that were flight-hunting being mobbed more than expected compared with ones that were perch-hunting. Kestrels were observed being mobbed throughout the year, and there was no discernible difference in their response to mobbing between seasons. These results are discussed in relation to current ideas on the functions of avian mobbing.
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Cowley, J. J., & Griesel, R. D. (1966). The effect on growth and behaviour of rehabilitating first and second generation low protein rats. Anim. Behav., 14(4), 506–517.
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Barnard, C. J., & Sibly, R. M. (1981). Producers and scroungers: A general model and its application to captive flocks of house sparrows. Anim. Behav., 29(2), 543–550.
Abstract: Many forms of interaction within and between species appear to be based on `scrounger' individuals or species exploiting a limited resource provided `producers'. A mathematical model is presented which shows whether or not scroungers are maintained in a group, depending on their frequency and the group size. Some of the predictions of the model were tested in captive flocks of house sparrows Passer domesticus L. Here the scroungers obtained most of their food (mealworms) by interaction and the producers found most of their food by actively foraging: the pay-off to each type was measured as mealworm capture rate. Neither type changed strategy opportunistically in response to instantaneous flock composition but, not surprisingly, scroungers fared better when one of more producers were present. However, scrougers did much worse than expected when greatly outnumbered by producers, perhaps because producers then found the available food very quickly.
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Taillon, J., & Cote, S. D. (2007). Social rank and winter forage quality affect aggressiveness in white-tailed deer fawns. Anim. Behav., 74(2), 265–275.
Abstract: Achieving a high social rank may be advantageous for individuals at high population densities, because dominance status may determine the priority of access to limited resources and reduce individual loss of body mass. The establishment of dominance relationships between individuals involves variable levels of aggressiveness that can be influenced by resource availability. The relationship between social rank and aggressiveness and the impacts of resource abundance on aggressiveness are, however, poorly understood, but may be relevant to understand the mechanisms determining dominance relationships between individuals. We experimentally simulated, in seminatural enclosures, a deterioration of winter forage quality induced by a high-density deer population and examined the effects of (1) social dominance and (2) diet quality on aggressiveness, forage intake and body mass loss of white-tailed deer, Odocoileus virginianus, fawns during two winters. Within diet-quality treatments, fawns were consistently organized into linear hierarchies and showed clear dominance relationships. Dominants initiated more interactions and showed higher aggressiveness than subordinates, but subordinates had higher forage intake than dominants throughout winter. Social rank did not influence cumulative body mass loss of fawns. During both winters, fawns fed the control diet maintained their aggressiveness level, whereas fawns fed the poor-quality diet decreased it. Our experimental approach revealed that white-tailed deer responded to a reduction in winter forage quality by modifying their aggressiveness, indicating that ungulates may show plasticity not only in their foraging behaviour in response to decreased resources but also in their social behaviour.
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Schloegl, C., Kotrschal, K., & Bugnyar, T. (2007). Gaze following in common ravens, Corvus corax: ontogeny and habituation. Anim. Behav., 74(4), 769–778.
Abstract: Co-orientation with others by using their gaze direction is considered to be adaptive for detecting food or predators or monitoring social interactions. Like the great apes, common ravens are capable of following human experimenters' gaze direction not only into distant space but also behind visual barriers. We investigated the ontogenetic development of these abilities by confronting birds with a human foster parent looking up (experiment 1) and behind visual barriers (experiment 3) and their modification by habituation (experiments 2 and 4). We tested a group of 12 hand-reared ravens during their first 10 months of life. Ravens responded to others' look-ups soon after fledging but could track their gaze behind a visual barrier only 4 months later, at the age they usually become independent from their parents. Furthermore, ravens quickly ceased responding to repeated look-ups by the model, but did not habituate to repeated gaze cues directed behind a barrier. Our findings support the idea that the two modes of gaze following reflect different cognitive levels in ravens and, possibly, have different functions.
Keywords: Corvus corax; gaze following; habituation; ontogenetic development; raven
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Bonnie, K. E., & Earley, R. L. (2007). Expanding the scope for social information use. Anim. Behav., 74(2), 171–18.
Abstract: Our understanding of how, why, and the circumstances under which animals use social information has been facilitated by three principal areas of research, social learning, public information use and social eavesdropping. With few exceptions, these related concepts have remained remarkably distinct within the literature, with little discussion or integration among them. Are these distinctions warranted? We tackle the issue by exploring similarities and differences between the concepts with respect to how animals gather and use social information, the type of information gathered, how information is packaged, and the relative payoffs to individuals involved. We contend that none of the currently dominant paradigms, social learning, public information use, or social eavesdropping, provide a unifying theme for studying social information use. Instead, we favour the central characteristic of the three concepts, social information use, as the overarching umbrella, and advocate a broader conceptual framework for understanding more comprehensively how animals behave with their social environments. Our intention is not to revolutionize the fields of social learning, public information use or social eavesdropping, but rather to stimulate discussion among researchers investigating the abilities of animals to extract information from the social environment.
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Henson, S. M., Dennis, B., Hayward, J. L., Cushing, J. M., & Galusha, J. G. (2007). Predicting the dynamics of animal behaviour in field populations. Anim. Behav., 74(1), 103–110.
Abstract: Many species show considerable variation in behaviour among individuals. We show that some behaviours are largely deterministic and predictable with mathematical models. We propose a general differential equation model of behaviour in field populations and use the methodology to explain and predict the dynamics of sleep and colony attendance in seabirds as a function of environmental factors. Our model explained over half the variability in the data to which it was fitted, and it predicted the dynamics of an independent data set. Differential equation models may provide new approaches to the study of behaviour in animals and humans.
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