The generation subculture theory asserts that as each generation comes of age and begins to harness political and economic power, their unique value-set will shape social and environmental outcomes. With this in mind, we undertook a preliminary social survey that explored the relationship between birth cohort (the Silent Generation, Baby Boomers, Generation X and Millennials), and marine environmental values, behaviour, and preferences. The findings demonstrate a declining value is placed on the marine environment across the generations, with an associated decrease in pro-environmental behaviours. The results emphasise the importance of targeted conservation outreach, particularly for Millennials.