Direct threats of ecotourism
Scuba divingScuba diving has become increasingly popular in many places around the world, but concerns exist that it is causing damage to many coral reefs. A study which looked at ways of managing scuba diving on Thailand's coral reefs, showed that 93% of divers made contact with corals; two thirds of which caused damage to them. [21].
Shark provisioning is also becoming an increasingly popular tourist activity, which may lead to the disturbance of marine habitats and the species that live within them. Work carried out by Fitzpatrick et al. (2011) showed that the behaviour of whitetip reef sharks was altered as a direct result of dive boats being present; which could result in a having a negative effect on their overall health (Fig. 3). [21]. Fig. 3 Triaenodon obesus (Whitetip shark)
[8] Domino effectSharks are vital for the health or coral reefs; and studies have shown that the loss of sharks may have contributed to the decline of reefs in the Caribbean [16]. Top predators are important for the maintenance of ecosystems, and removal of them allows other predators to thrive. This could lead to the reduction in the number of gregarious fish species such as parrotfish and surgeonfish [16].
A similar effect has been described by Mc Clanahan & Shifir. (1990), when overfishing had removed gregarious fish speices in Caribbean reefs in the 1970"s. This was followed by a disease that wiped out out sea urchins, allowing algae to thrive. |
TramplingHuman trampling is a common disturbance caused to reef systems that can be caused by swimming and snorkelling (Fig. 4). A study of human trampling effects on Harpacticoida species in reef formations in Brazil revealed that species were most abundant and of higher densities in protected areas compared with areas subject to intensive tourism [18].
Fig. 4 An atoll reef system in the Maldives that has been effected by human trampling.
PollutionPopulation pressures from ecotourism can lead to the accumulation of pollution and rubbish associated with western lifestyles, and normal day to day activities such as eating, drinking and using the toilet can have a major impact on the environment. A study carried out by Burgin & Hardiman. (2011) looked at the impacts on Australian coastal waters from recreational boating and found that most critical chemical impacts results from pollution from fuels and human waste.
Recreational boatingRecreational boating can also have major physical impacts on coral reef communities including disturbance due to movement of craft in shallow waters and effects of anchoring and collisions that may impact marine life [2]. Likewise, the demand for recreational vessels has significantly increased in recent years, and is likely to continue to do so [2].
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