Skip to main content

Verified by Psychology Today

Dolphins Who Hang With Mates Display a Positive Spin on Life

Study shows dolphins who swim together display positive emotions and optimism

"Hanging with your mates may put a positive spin on life"

A few hours ago, when I was looking for some information on another topic, I came across an essay by Ramin Skibba called "Synchronised swimming seems to make dolphins more optimistic." The caption to an image accompanying the article reads, "Hanging with your mates may put a positive spin on life."

Mr. Skibba's essay focuses on a research paper published in Behavioural Brain Research by Dr. Isabella Clegg and her colleagues titled "Bottlenose dolphins engaging in more social affiliative behaviour judge ambiguous cues more optimistically." I honestly didn't see the main message of this extremely interesting and intriguing study until I saw Mr. Skibba's summary.

The highlights for this research essay are online and read:

First 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.

The abstract for this study reads:

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.

Cutting to the chase, this study shows "Bottlenose dolphins that engage in synchronised swimming with their peers tend to see the glass as being half full." When dolphins swam toward an object on the left they received eye contact and applause, and when they swam toward an object on the right, they received much-loved herring. When they were offered an ambiguous target, the researchers showed that the dolphins who swam together were the more optimistic individuals and swam faster than other dolphins. The effect lasted around two months, after which it declined. 

Mr. Skibbas writes, "Swimming together is an important social activity for dolphins that increases bonding between them, and the researchers argue that it could be linked to positive emotions," and lead researcher Isabella Clegg notes, "I think it’s the social behaviour that drives the dolphins’ optimistic decisions." And, it's known that wild dolphins bond as a result of synchronous swimming. Along these lines, Mr. Skibba writes, "The dolphins’ optimistic behaviour resembles 'cognitive bias': how humans judge situations differently depending on their social environment. People’s social activity affects their outlook on the world, and something similar may happen among some animals, too."

What I really like about this study in addition to showing that dolphins who swim together display more optimism, is that it also has practical applications in that social interactions might make captivity less stressful for individuals who are able to socialize with peers. Mr. Skibba concludes, "Clegg agrees. Zookeepers and aquarists could use this to monitor how many dolphins often swim together, and manage their practices accordingly. 'In better welfare situations, animals judge [things] more optimistically,' she says."

I really like this study and I hope other researchers will follow up with additional comparative studies on other species. Social interactions can be very positive for individuals in a wide variety of species, and not only can we learn about wild animals, but also those who are forced to live in captive conditions where they have little to no freedom to make choices about how they want and need to spend their time

Marc Bekoff’s latest books are Jasper’s Story: Saving Moon Bears (with Jill Robinson), Ignoring Nature No More: The Case for Compassionate Conservation, Why Dogs Hump and Bees Get Depressed: The Fascinating Science of Animal Intelligence, Emotions, Friendship, and Conservation, Rewilding Our Hearts: Building Pathways of Compassion and Coexistence, and The Jane Effect: Celebrating Jane Goodall (edited with Dale Peterson). The Animals’ Agenda: Freedom, Compassion, and Coexistence in the Human Age (with Jessica Pierce) will be published in April 2017 and Canine Confidential: An Insider’s Guide to the Best Lives For Dogs and Us will be published in early 2018. His homepage is