The critically endangered east coast population of the Grey Nurse Shark (GNS) (Carcharias taurus) are an ideal species for marine wildlife tourism (MWT). With 90% of the observed population aggregating at 14 identified critical habitat sites they are easily and reliably accessible, while their placid nature provides opportunities for divers to interact with large sharks without the need of protective cages. This increases their vulnerability to anthropogenic impacts. Understanding the human dimensions of shark interactions, including diver attitudes and behaviours can provide important inputs to conservation management actions and MWT operations. This study applied the frameworks of the Theory of Planned Behaviour (TPB) and recreation specialisation (RS) to examine the motivations, attitudes and behaviours of divers at the critical GNS aggregation site of Flat Rock, North Stradbroke Island. The data highlights the importance of diver experience and subjective norms in influencing diver behaviour. A model is suggested that places shark divers on Bryan’s RS continuum, noting that as divers progress along the continuum from generalists to specialists, their motivations shift from the thrill and status of the encounter, to be more aligned with increasing shark related conservation issues and that they exhibit more pro-environmental behaviours and beliefs.