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Lusseau, D., & Conradt, L. (2009). The emergence of unshared consensus decisions in bottlenose dolphins. Behav. Ecol. Sociobiol., 63(7), 1067–1077.
Abstract: Abstract Unshared consensus decision-making processes, in which one or a small number of individuals make the decision for the rest of a group, are rarely documented. However, this mechanism can be beneficial for all group members when one individual has greater knowledge about the benefits of the decision than other group members. Such decisions are reached during certain activity shifts within the population of bottlenose dolphins residing in Doubtful Sound, New Zealand. Behavioral signals are performed by one individual and seem to precipitate shifts in the behavior of the entire group: males perform side flops and initiate traveling bouts while females perform upside-down lobtails and terminate traveling bouts. However, these signals are not observed at all activity shifts. We find that, while side flops were performed by males that have greater knowledge than other male group members, this was not the case for females performing upside-down lobtails. The reason for this could have been that a generally high knowledge about the optimal timing of travel terminations rendered it less important which individual female made the decision.
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Mills, D. S., & Taylor, K. (2003). Field study of the efficacy of three types of nose net for the treatment of headshaking in horses. Vet. Rec., 152(2), 41–44.
Abstract: Thirty-six owners of seasonally headshaking horses took part in a trial to compare the effectiveness of three types of nose net, a traditional cylindrical net (full net) and two forms of larger mesh nets which cover only the nostrils and dorsorostral muzzle (half nets). Baseline data relating to the overall severity of the problem and 18 specific behaviours describing the nature of the problem were recorded on a check sheet by the owners. A within-subjects repeated measures design experiment, with each net used for a week before reassessment, was then used to assess the effect of the nets on the headshaking problem. Approximately 75 per cent of owners reported some overall improvement with each net; around 60 per cent recorded a 50 per cent or greater improvement and 30 per cent a 70 per cent or greater improvement. The nets significantly reduced the overall headshaking score and the following specific behaviours: up-and-down headshaking, nose flipping, acting as if a bee had flown up the nose, shaking at exercise, shaking when excited, shaking in bright sunlight or in windy conditions (P < 0.0001), striking at the face, shaking at night, rubbing the nose when moving, rubbing the nose on objects, sneezing, shaking in the rain and shaking indoors (P < 0.05). There was no evidence of a significant effect on side-to-side headshaking, shaking at rest or rubbing the nose when stationary, but the effect on snorting was uncertain. There were few significant differences between the nets, but the half nets were reported to be significantly better at controlling 'bee up the nose' behaviour. Horses more than 10 years old were reportedly less likely to show a 50 per cent or greater improvement in 'nose flipping' and 'headshaking at exercise.
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Sakai, M., Hishii, T., Takeda, S., & Kohshima, S. (2006). Laterality of flipper rubbing behaviour in wild bottlenose dolphins (Tursiops aduncus): Caused by asymmetry of eye use? Behav. Brain. Res., 170(2), 204–210.
Abstract: To determine whether wild Indo-Pacific bottlenose dolphins (Tursiops aduncus) at Mikura Island, Japan, show asymmetry of eye or flipper use during a social behaviour, we investigated the laterality of flipper-to-body (F-B) rubbing, in which one dolphin (“rubber”) rubs the body of another (“rubbee”) with its flipper. We analysed 382 episodes of video-recorded F-B rubbings performed by identified individuals (N = 111 rubbers). F-B rubbing was conducted significantly more frequently with the left flipper than with the right flipper. The duration of F-B rubbings was also significantly longer with the left flipper than with the right flipper. Of 20 dolphins, nine individuals showed significant left-side bias as the rubber in this behaviour, whereas no dolphins showed significant right-side bias. The results indicate a population-level left-side bias of the rubber in F-B rubbing. An analysis of the swimming configurations during this behaviour suggests that the asymmetry in F-B rubbing was caused not only by the laterality of the rubber, but by a preference for use of the left eye in both dolphins during this behaviour. Dolphins used the left eye significantly more frequently than the right eye during the inquisitive behaviour, while they showed no significant bias in flipper use during the object-carrying behaviour. These facts also suggest that the asymmetry of F-B rubbing is caused by the preference for using the left eye. Significant left-side bias was observed only in F-B rubbings initiated by the rubbee, in which the rubbee determined its position during this behaviour. This suggests that this behavioural asymmetry was enhanced by the rubbees choosing the left side of the rubber to ensure better and longer rubs.
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Stout, I. J., Clifford, C. M., Keirans, J. E., & Portman, R. W. (1971). Dermacentor variabilis (Say) (Acarina: Ixodidae) established in southeastern Washington and northern Idaho. J Med Entomol, 8(2), 143–147.
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