Evaluating the impact of Blue Planet II on viewers' plastic consumption behaviours

New research from the University of Oxford and Imperial College, London seeks to discover how effective the TV series Blue Planet II was in changing plastic consumption.

High levels of messaging about conservation, and in particular ocean plastic pollution, in the TV series Blue Planet II has been said to have created a 'Blue Planet Effect' which changed viewer’s consumption of plastic. Researchers used actual observations of people’s preference for plastic, rather than relying on individuals reporting their own preference (which can be unreliable). 

Published in The Society for Conservation Biology, participants were randomly assigned to one of two different groups using a Randomised Control Trial. One group was shown the treatment condition (watching Blue Planet II) and the other was shown a control condition. The control condition was the documentary series The Blue Planet, which is a nature show about marine life that doesn’t discuss environmental issues or ocean plastics, as our control condition. 

Participants filled in a questionnaire both before and after watching the respective documentary which measured their understanding of and attitudes towards marine conservation issues. Any changes observed in participants’ questionnaire scores from before to after watching either Blue Planet II or The Blue Planet were compared across the two groups. 

In order to measure individual’s preference for plastic, participants were offered a choice of snacks and drinks to have during their viewing of Blue Planet II or The Blue Planet. These snacks were presented in both plastic and paper packaging. Researchers controlled for any other differences between the options, such as favours or sizes of the snacks, for example by offering the same soft drinks in both plastic and paper cups. Participant’s choices were observed both before and after watching Blue Planet II or The Blue Planet and it was noted whether they choice was for a snack in paper or plastic packaging.  

Researchers found that people’s knowledge about environmental issues increased significantly after watching Blue Planet II. However, this increased awareness did not lead to a change in behaviours, as people’s likelihood to choose plastic did not significantly change after watching Blue Planet II. 

The findings of this research contradict the popular hypothesis that Blue Planet II reduced viewer’s preference for plastic, demonstrating that information will not change behaviour by itself, it needs to be embedded within a wider range of initiatives. These findings are the first to use this type of experimental design along with measuring observed behaviours to test this hypothesis. 

However, this paper also discusses the possibility that Blue Planet II had a wider impact through its ability to increase conversations around ocean plastic pollution, allowing the topic to become more politically palatable and influencing the policy changes that came into effect after the airing of Blue Planet II. 

Going forward, researchers plan to use this evaluation method to test the effectiveness of other conservation related mass media interventions on changing individual behaviours.