Effects of recreational scuba diving on Mediterranean fishes: evidence of involuntary feeding?

Abstract

Despite a large body of literature assessing the impacts of recreational scuba diving on marine habitats, little attention has been paid to the potentially harmful effects this has on fishes. The aim of this study was the assessment of the immediate response of different fish species to divers’ activities. A decrease of fishes’ natural diffidence towards divers is shown, probably due to an enhanced availability of their prey as a result of divers’ contacts with the substrate.

Comparison of efficiency of direct observations by scuba diver and indirect observations via video camera for measuring reef‐fish behaviour

“…In fact, given the necessity for observers to be in close proximity to the studied animals and the visual, olfactory, auditory and somatosensory cues produced by divers, observer presence might be reasonably assumed to influence behaviour (Lobel, 2005;Radford et al, 2005). Indeed, the question of whether the presence of divers influences fish behaviour, has been previously addressed (Barker et al, 2011;Cubero-Pardo et al, 2011;Di Franco et al, 2013;Nanninga et al, 2017;Smith et al, 2010;Titus et al, 2015). Overall, there is some evidence in the literature demonstrating that divers influence fish behaviour (Brignon et al, 2011;Byerly & Bechtol, 2005;Chapman et al, 1974;Dickens et al, 2011;Schmidt & Gassner, 2006;Stanley & Wilson, 1995) but different species respond differently to human presence (Cole et al, 2007;Dearden et al, 2010;Kulbicki, 1998;Thresher & Gunn, 1986;Watson & Harvey, 2007).…”

2. Using Of Natural Spaces For Tourism Activity Scuba Diving And Impacts On Aquatic Animals

“…Moreover, it gives better chance to the reef system to be free from human impacts (Musa et al, 2010). Di Franco, Baiata, and Milazzo, (2013) have studied about underwater impacts from recreational scuba diving worldwide, which majority is focus on potential disturbance on benthic zones, and just few are directed to motile species. These last reflex studies on interactions fish-human when fish-feeding occurs.…”

“…Studies about scuba diving, are mostly highlighting socio-economical perspective, or impacts on the bottom of the water-bodies (Di Franco et al, 2013), some others report divers' performance and comfort level (Dimmock, 2007) for underwater behavior towards good diving practices in benefit of the environment (Musa et al, 2010). Diver skills and education have been targeted for commercial use and access to interest groups (Dimmock, 2004).…”

“…Scuba diving as itself does not harm the environment, but these suffer from side activities necessary for providing comfort and safety. Unless divers grab, touch or harass marine animals (Franco et al, 2013;Siti and Badaruddin, 2014), the activity follows good ethics and does not disrupt normal activity on the reef, and the only accountable impact is "leave bubbles".…”

“…Facts show severe impacts created from divers associated to physical destruction, it is very importance to master diving techniques and raise awareness of how divers can damage such fragile environment (Franco et al, 2013). It is also important to understand the impact created by the activity (Musa et al, 2010), and therefore adopt 'safety for all' on the reef.…”