"Take only photographs and leave only footprints"?: An experimental study of the impacts of underwater photographers on coral reef dive sites

Impacts caused by recreational scuba diving on coral reefs vary widely amon g different dive locations and individual divers. Linear modelling was used to explore a range of individual and situational risk factors associated w ith divers who damaged corals in the Great Barrier Reef Marine Park. Recrea tional divers were followed for 10-15 min, and all contacts with, and damag e to corals were recorded. Information on the dive site, during experience, gender, and use of an underwater camera were recorded. Thirty-two out of 2 14 divers (15%) damaged or broke corals, mostly by fin kicks (95%). Impacts were most likely to be caused by male divers, in the first 10 min of the d ive, at sites with a large abundance of branching corals. Specialist underw ater photographers caused more damage on average (1.6 breaks per 10 min) th an divers without cameras (0.3 breaks per 10 min). To explore the effects o f gender and use of a camera further, we issued single-use underwater camer as to 31 randomly chosen divers and compared their behaviour to a control g roup. Use of a camera had no influence on the rate or amount of damage caus ed by these naive photographers, but male divers were more likely to break corals and caused significantly more damage, on average, (1.4 breaks per 15 min) than female divers (0.3 breaks per 15 min). Variability in the amount of damage caused by divers in our sample reflected the very different unde rwater behaviours exhibited by specialist, and non-specialist photographers . and male and female divers. Greater understanding of the causes of harmfu l behaviours by these groups will allow better targeting of on-site interpr etative and cautionary information and may prove to be a more palatable man agement strategy than regulation of site use. (C) 2001 Elsevier Science Ltd . All rights reserved.