Fabienne Delfour

Inter-modal learning task in bottlenosed dolphins (Tursiops truncatus): a preliminary study showed that social factors might influence learning strategies

We studied the dolphin’s capacity to perform a cognitive task when information arrives through two different sensory modalities (visual and auditory). Three female bottlenosed dolphins (Tursiops truncatus) were submitted to a two-, three-, or four-choice visually combined with auditory discrimination problem without any food reward. Since they were not isolated, we examined the significance of the role of identified social constraints on the learning process. The results tended to show an ability to associate simple visual forms and auditory information using an underwater touchscreen. This task was learnt in various ways according to identified social constraints. For each subject, we examined and discussed the number of successful answers, their ability to focus attention on the test and to acquire, or not, the specific task, while noting influences of the social interactions and the social hierarchy on the whole acquisition process.

Bottlenose dolphins engaging in more social affiliative behaviour judge ambiguous cues more optimistically

HighlightsFirst cognitive bias test application to a marine mammal or zoo‐housed species.Stable individual differences in judgements of ambiguous cues were found.Dolphins performing more synchronous swimming made more optimistic judgements.Longer‐term behavioural data suggest results reflected a transitory affective state.Results support hard‐to‐measure link between social affiliation and positive affect. Abstract Cognitive bias tests measure variation in emotional appraisal and are validated methods to assess animals’ affective states. However, the link between social behaviours and cognitive bias has not yet been investigated. Bottlenose dolphins are a gregarious species for whom welfare research is increasing in importance, and thus are a good model to test such an association. We adapted a spatial location judgement bias test for eight captive bottlenose dolphins to investigate the link between cognitive bias and social behaviour, where we conducted behavioural observations outside of training sessions and did not experimentally induce an affective state. Subjects showed stable individual differences in cognitive biases across the three test days. Furthermore, dolphins showing more synchronous swimming, a fundamental affiliative behaviour, judged ambiguous cues significantly more optimistically. Our longer‐term data showed cognitive bias and synchronous swimming frequency were significantly associated for up to two months preceding the test, but disappeared prior to that, suggesting that here cognitive bias differences were reflected by transitory affective states rather than longer‐term traits. We hypothesise that the frequency of synchronous swimming may induce affective states and/or be induced by them; either way, it has strong potential as an indicator of affective state in this species and beyond.

Schedule of Human-Controlled Periods Structures Bottlenose Dolphin (Tursiops truncatus) Behavior in Their Free-Time.

Behavioral patterns are established in response to predictable environmental cues. Animals under human care frequently experience predictable, human-controlled events each day, but very few studies have questioned exactly how behavioral patterns are affected by such activities. Bottlenose dolphins (Tursiops truncatus) maintained for public display are good models to study such patterns since they experience multiple daily human-controlled periods (e.g., shows, training for shows, medical training). Thus, we investigated the effect of training session schedule on their “free-time” behavior, studying 29 individuals within 4 groups from 3 European facilities. Our initial time budget analyses revealed that among the behaviors studied, dolphins spent the most time engaged in synchronous swimming, and within this category swam most at slow speeds and in close proximity to each other. “Slow-close” synchronous swimming peaked shortly after training sessions and was low shortly before the next session. Play behavior had significantly higher frequencies in juveniles than in adults, but the effect was only seen during the in-between session period (interval neither shortly before nor after sessions). Anticipatory behavior toward sessions was significantly higher shortly before sessions and lower afterward. We conclude that dolphin behaviors unconnected to the human-controlled periods were modulated by them: slow-close synchronous swimming and age-dependent play, which have important social dimensions and links to welfare. We discuss potential parallels to human-controlled periods in other species, including humans themselves. Our findings could be taken into account when designing welfare assessments, and aid in the provision of enrichment and maintaining effective schedules beneficial to animals themselves.

Does Enrichment Improve Well Being in Animals under Human Care? A Case Study of Two Harbor Seals (Phoca Vitulina)

ABSTRACT Harbor seals in the wild live in a stimulating environment; therefore, nonhuman-animal caretakers have increasingly been using environmental enrichment to improve the well being of seals under human care. The purpose of this study was to evaluate an object-based environmental enrichment program during a four-month period on stimulating exploration and play and improving conspecific social interactions and human–animal relationships (HAR). Zoo staff conducted the environmental enrichment program as part of the animal care program. Seals were given objects haphazardly and were observed for 20 minutes, and seals’ responsiveness during training sessions before and after enrichment was assessed. Seals showed interest in objects throughout the study and interacted more times per session with objects during the later months. Seals showed preferences for objects that were suspended in the water column (e.g., rope). Seals did not show more affiliative behavior but did show some aggressive behavior during enrichment sessions in comparison with free-swimming sessions. One seal showed better responsiveness to trainers in training sessions that followed an enrichment session than in other trainings sessions. Overall, the enrichment program was successful in increasing intrinsically motivated behaviors and showed that object-based enrichment has the potential to improve HAR between seals and their trainers.

Does emotional state influence motor lateralization in California sea lions ( Zalophus californianus )

Motor lateralization is a behavioural asymmetry between the left and the right side of an individual due to hemispheric specialization. The right hemisphere controls the left side of the body and the left hemisphere the right side. The right hemisphere processes negative emotions such as fear and frustration, and on the contrary, the left hemisphere processes positive emotions such as happiness. This study, conducted at Parc Asterix Delphinarium (Plailly, France), tested the influence of supposedly positive, negative and neutral emotional situations on four California sea lions’ (Zalophus californianus) motor lateralization while performing a known exercise, here climbing on a stool. Latency between the caretakers’ command and the animals’ response was recorded. The results showed an interindividual variability in the effect of the supposed emotional situations on their motor lateralization and their response latency. The nature and the strength of this effect require deeper investigation by further studies, on a larger number of individuals and contexts.