Human-Animal Interactions And Captive Dolphin Welfare
For animal advocates, trying to get the general public to see animals as sentient individuals can be a challenge. Though we may succeed in convicing people that animals have emotions and feel pain, we may have a harder time making the case that individual animals of the same species experience the world differently. Here at Faunalytics, we’ve seen some studies that gesture towards this, such as this study, which looks at the differences between optimistic and pessimistic pigs.
This study was conducted by researchers who wanted to study the relationship between animals’ anticipatory behavior and their mental state. Furthermore, they wanted to study the motivation behind anticipatory behavior for non-food rewards, like playtime or belly rubs. This is a relatively unexplored topic in animal-related research and has implications for the measurement of captive animal welfare.
The research was conducted in a French zoo on seven bottlenose dolphins of various ages, with three being wild-caught, and four born in captivity. Enrichment and food rewards were scheduled at least once per day, often multiple times. These rewards were preceded by a sound cue, which could be heard throughout their indoor and outdoor pools. The dolphins had never heard these sounds before, and a control sound was used to rule out the possibility that they weren’t simply responding to a new sound.
The researchers used Pavlov’s classical conditioning model, which is the standard for studies of anticipatory behavior. In this model, a stimulus is given, followed shortly afterwards by a reward. Through repetition of this pairing, the animals eventually come to expect the reward upon sensing the stimulus. In Pavlov’s original experiment, he trained dogs to salivate at the sound of a bell by feeding them whenever the bell rang. Even in the absence of food, the dogs would salivate – their minds had paired the bell with the expectation of food.
Three types of rewards were used for the experiment: a trainer playing with or petting the dolphins, adding a toy to the pool, and feeding the dolphins. To measure their level of anticipation, researchers recorded two dolphin behaviors: looking at the surface of the water and spy hopping (poking their heads out of the water). To ensure the experiment wasn’t compromised, no other human activity around the tank was allowed for its duration.
The dolphins were found to be much more likely to perform anticipatory behavior when they heard the sounds that preceded rewards compared to the control sound. The researchers found dolphins that performed the most anticipatory behaviors were more likely to participate in the rewards. Generally, the dolphins preferred interacting with trainers to receiving food or a toy. However, the strength of this preference varied between each dolphin – as we would expect with individual beings.
This study is, admittedly, very small. The data from seven dolphins in a single zoo is not enough to extrapolate onto all animals, and certainly not all captive animals. Different animals will behave differently, and it is possible that many will completely “fail” to perform anticipatory behavior. For their part, the researchers recognized the limitations of their study, and call for more research covering greater numbers of animals and more species.
If the results of this study hold true for other species, it could be greatly beneficial for captive animal welfare. By measuring levels of anticipatory behavior, trainers and handlers could determine what forms of enrichment animals enjoy the most. Instead of just throwing a toy into an enclosure, the zoo could conduct research to determine what individual animals prefer in terms of enrichment and interaction. Some animals will prefer toys, some will prefer food, and some will prefer interaction.
This is one step in recognizing animals’ individual personalities and preferences. As we learn more about the cognitive capacities of animals, we will hopefully come to see them as individual beings, like we do with humans. A daycare that only provides one kind of enrichment would be rightly criticized for treating all children as the same, when we know that different children have different preferences. Studies like these will be crucial in breaking down the communication barrier that often prevents humans from seeing animals as individuals, and could, by extension, lead to people questioning the captivity of animals in zoos as such.