After reviewing volunteer tourist motivations generally, 804 domestic visitors to two National Parks in Australia's Gold Coast region were surveyed to identify the motivations and barriers that would either facilitate or inhibit participation in a range of 20 hypothetical volunteering and “quasi-volunteering” site enhancement activities, both on- and off-site, that could help achieve park/visitor symbiosis. Factor analysis of 24 motivation items from the valid returned questionnaires revealed “altruism”, “personal wellbeing” and “personal status” dimensions, with only the first two attracting overall positive means. Variable support for these site enhancement activities, however, was evident when motivation means and factor scores were calculated for visitor segments identified earlier. Clusters open to participation yielded higher motivation levels, but the “altruism” dimension showed a greater range from higher to lower willingness. Throughout, the motivation scores of females were higher. Distance and time were the main barriers to participation, with low amenability clusters yielding the highest level of perceived barriers. The results suggest that motivations of altruism and selected self-interest should be combined in strategies to attract and satisfy participants in protected area site enhancement, to develop aspects of the ecotourium concept and capitalise on the growing interest in personal wellbeing.