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Asia-Pacific Network for Global Change Research

Asia-Pacific Network for Global Change Research

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Ocean acidification and implications of the COVID-19 pandemic for the SCUBA diving industry in four regions in Asia-Pacific

Long-term and short-term challenges for the dive industry


Coral reefs are living structures built from the accretion of calcium carbonate. Ocean acidification is a chronic problem that influences the availability of carbonate ions required to build reefs (Figure 1) (Albright et al., 2018) and increases the risk of reef dissolution (Eyre et al., 2018). Ongoing decreases in pH are predicted under all future Earth System Models (IPCC, 2019). This could drive coral reefs towards their tipping point (Figure 1), with a net loss of coral and associated reefs communities predicted to occur this century (Cooley et al., 2022). This will have serious implications for regional communities that are dependent on coral reefs for their livelihoods.

Figure 1: Conceptual model of the impacts of ocean acidification and dive tourism on coral reefs. An online survey of SCUBA divers, along with dive industry stakeholder interviews undertaken in four Asia Pacific regions were used to assess the state of knowledge on ocean acidification. This will feed into a risk assessment and inform the need for further education and management of coral reefs.
Figure 1: Conceptual model of the impacts of ocean acidification and dive tourism on coral reefs. An online survey of SCUBA divers, along with dive industry stakeholder interviews undertaken in four Asia Pacific regions were used to assess the state of knowledge on ocean acidification. This will feed into a risk assessment and inform the need for further education and management of coral reefs.

Ocean acidification is a complex scientific and management problem that will impact many Asian Pacific Nations that rely heavily on coral reefs for on marine-related economic activities (Cooley, Kite-Powell, & Doney, 2009). Southeast Asia is one of the world’s leading recreational scuba diving destination (Dimmock & Musa, 2015). The combined effects of ocean acidification and marine tourism activities could place intense pressure on sensitive reefs and threaten their ecological and economic sustainability. As corals become more fragile under acidified conditions, their susceptibility to others forms of damage will increase. Dive tourism is known to have some negative impacts on coral ecosystems, such as damaged caused through contact with the reef by boat anchors, fin kicks and poor buoyancy (Juhasz, Ho, Bender, & Fong, 2010; Noh, Shuib, Tai, & Noh, 2018; Praveena, Siraj, & Aris, 2012). The impacts from this type of damage is likely to be exacerbated under acidified conditions.

The combined effects of acidification and scuba diving on increasingly sensitive coral reefs requires effective management to ensure the protection of ecological, cultural and economic values. Managing the impacts of divers on coral reefs requires stakeholder engagement to implement non-regulatory strategies such as education. A study of stakeholder awareness of the importance of coral reef conservation in Perhentian Island revealed variable awareness and some denial of the damaging effects of snorkeling and diving (Saleh & Hasan, 2012). Improved awareness of the threat from ocean acidification could help engender a sense of stewardship in the dive industry , thus improving quality of pre-dive briefings and encouraging good dive technique. Effective education and leadership can encourage the necessary ‘future oriented thinking” (Dimmock & Musa, 2015) for sustainable marine tourism in a changing world.

Awareness of ocean acidification in the dive industry

To assess the level of awareness of ocean acidification in the dive community, we undertook stakeholder interviews with Dive masters in four Asia Pacific regions: 1) Solitary Islands Marine Park, Coffs Harbour, Australia, 2) Hon Mun Marine Protected Area, Nha Trang, Vietnam, 3) Ambon Island, Maluku Archipelago, Indonesia and 4) Tioman Island, East Coast Malaysia. Additional interviews were undertaken with Marine Managers in Nha Trang and Ambon (Table 1). An online survey was also distributed through social media networks and 67 SCUBA divers responded to the question “Before today, had you heard of Ocean Acidification?” We further divided these responses according to their level of dive certification and responses were further collated for divers with Australia, Malaysia or Indonesia identified as their country of origin (no Vietnamese divers completed the survey). Overall, we found an increase in the level of awareness of Ocean Acidification with higher levels of SCUBA dive certification and experience (Table 1).

The Solitary Islands Marine Park has a relatively small dive industry (4 commercial providers), and generally have good environmental awareness. Over 90% of Australian divers who completed the online survey were aware of ocean acidification (Table 1). Nevertheless, only 50% of the dive masters in the Solitary Islands Marine Park interviewed had prior knowledge of ocean acidification, although based on a small sample size (n=4). The two Australian Dive masters who were aware of ocean acidification identified it as a major threat to coral reefs. Furthermore, I the online diver survey, 9 of the 12 participants who specifically identified ocean acidification as a threat to coral reefs were from Australia, with a further two from the USA and the other with no identified country of origin.

Hon Mun Marine Protected area has rapidly grown as a popular dive spot in the last decade, with a burgeoning local and foreign tourist industry in Nha Trang. The Dive Masters and Marine Park Managers from this region report a high level of awareness of ocean acidification (89 and 90% respectively, Table 1). However, unlike the Australians, none of the Vietnamese, participants defined ocean acidification or identified it as a threat to coral reefs. However, all of the Marine Park Managers and one third of the Vietnamese identified climate change, ocean warming or coral bleaching as a threat (Table 2).

Ambon Island has been identified as a high priority for biodiversity conservation in recent assessment of marine biodiversity in the Coral Triangle [16]. It is a relatively untapped area for dive tourism in a biodiversity hotspot, with just four commercial operators at the time of the surveys. None of the dive Masters (Table 1) or the Marine Manager interviewed from Ambon Island) had heard of ocean acidification prior to the survey, but the sole Indonesian diver who completed the online survey had heard of it (Table 1). Of the dive managers in Ambon, 57% considered climate change to be a threat to coral reefs in their region.

The Malaysia Islands are coral hotspots and have been identified as ecotourism destinations. Tioman Island is recognized as the most popular island for the tourism industry (Hanim & Redzuan, 2010). The dive Masters from this region showed a good level of awareness of ocean acidification (67%, Table 1), although none considered it to be a priority threat and only 37% identified climate change as a threat (Table 2). Similarly, 67% of Malaysia divers who completed the online survey were aware of ocean acidification (Table 1), but none identified it as a major threat to coral reefs.

Awareness of diver-induced damage and human impacts

The majority of stakeholders in this study considered the coral reefs in their area to be in a state of decline and identified various human impacts as a major cause (Table 2). Only one of the Australian dive masters identified damage for diving or marine tourism as a risk, although diver induce damage has been previously reported from the Solitary Islands Marine Park (Hammerton & Bucher, 2015). Nevertheless, the relatively small number of marine tourism operators, strict regulations and high levels of education in Australia suggest these subtropical reefs are at lower risk from human activities than the other case study regions in the Asia Pacific.

Diving and tourism activities were infrequently identified as threats by the dive masters or marine managers in Nha Trang (Table 2). However, in a follow up question specifically asking participants whether they agreed diving and boating activities could have negative impacts, 44% of dive masters, but only 7% of Marine Park Mangers agreed. Nevertheless, the majority consider the reefs to be in decline as a result of various human activities (Table 2). A Reef Check programme has been implemented in Vietnam, which has demonstrated degradation of the coral reefs around Nha Trang (Long & Vo, 2013). Large boats of tourists focused around Hon Mun Island in particular could be contributing to observed coral damage and decline.

Diving or risks associated with marine tourism were not identified by any of the participants form Ambon and despite a range of human impacts that were identified, only 57% of these participants considered the reefs in this region to be in decline. This correlates with our observations of some incredibly diverse and pristine reefs on islands surrounding Ambon despite significant impacts in Ambon Harbour (Edinger, Kolasa, & Risk, 2000). The biodiversity value of these reefs, along with the limited knowledge of ocean acidification or potential for diver impacts, leaves these coral reefs quite vulnerable to potential expansion of tourism in the region, without effective management.

Unsustainable coastal development and uncontrolled tourism activities are though to be causing to the declining of corals in Tioman Island (Shahbudin, Akmal, Faris, Normawaty, & Mukai, 2017). Indeed, a relatively high percent of Malaysia Dive Masters identified diver and tourism related damage as a problem (68% Table 2). However, most of these dive Masters appropriately commented that it was only a problem if done excessively and without precautions or training. A Reef Check programme has been implemented in Malaysia to facilitate marine parks management and diver education (Wetzelhuetter, Chelliah, & Chen, 2014). The outcomes of our survey are encouraging, supporting the positive impacts on diver awareness that can stem from programmes like this.

Table 1: Summary of the awareness of ocean acidification in the scuba dive industry and different cohorts of scuba divers in response to the question, “Before today, had you heard of Ocean Acidification?”
Stakeholder group Yes No Percentage
Australian dive masters 2 2 50%
Nha Trang dive masters 16 2 89%
Nha Trang Marine Park managers 14 1 90%
Ambon dive masters 0 7 0%
Malaysian dive masters 13 6 68%
Scuba divers (online survey All) 46 19 71%
         Australian divers 21 2 91%
         Malaysian divers 10 5 67%
         Indonesian divers 1 1 50%
Certificate level
         Open water 2 3 40%
         Advanced 13 8 62%
         Rescue/Research/Scientific/Tec 50 12 4 75%
         Master 9 3 75%
         Instructor/Course Director 10 2 83%
Table 2: The proportion of stakeholders that mentioned ocean acidification (or pH) and/or climate change in response to questions about the main threats1 to coral reefs. This is compared to the number of stakeholders who referred to diver damage or marine tourism as a threat, or more generally, human impacts2 and consider coral reefs as currently in a state of decline3.
Stakeholder group Acidification Climate change Divers/ Tourism Human Impacts Reefs in decline
Australian dive masters 2/4 3/4 1/4 4/4 3(minor)/4
Nha Trang dive masters 0/18 6/18 2/184 13/18 15/18
Nha Trang Marine managers 0/15 15/15 1/15 15/15 14/15
Ambon dive masters 0/7 4/7 0/7 6/7 4/7
Malaysian dive masters 0/19 7/19 13/19 17/19 17/19
Scuba divers (online survey) 12/65 40/68 28/68 65/68 17/19

1 The question about threats was open ended for the dive industry stakeholders, but for SCUBA divers in the online survey reference to climate change is take from responses to a question asking them to identify the top three significant threats to coral reefs, whereas reference to ocean acidification is taken from the same if specifically identified or responses to a question asking what they think about with respect to impacts of climate change on coral reefs. Climate Change encompasses ocean warming, global warming, rising temperatures and coral bleaching in the summarised results.

2 Human impacts include diving, boating, tourism, fishing and pollution, but not climate change.

3 Stakeholders were also asked about whether they considered the reefs in their region to be declining in health since they commenced diving and this is broadly categorised into yes or no responses.

4 In an additional question specifically about potential for diver and tourisms impacts 8/18 diver Masters and 4/15 marine park managers answered yes.

Implications of the COVID-19 pandemic for the dive industry

In 2020, the progress of this project became significantly hampered by the global COVID pandemic. The borders of participating countries closed and most countries went into lock down. This restricted our ability to travel to undertake stakeholder interviews, but is likely to have had an even more significant impact on the livelihoods of many stakeholders in the dive industry due to a cessation of international tourism and temporary drops in the domestic market. However, the length and magnitude of impacts is likely to have varied between countries (Table 3).

In Australia, the borders were closed to international tourists for 2 years. However, complete lockdowns were relatively short, thus allowing domestic travel, at least within states and territories for most of this time (Table 3). The Government also provided financial assistance to impacted businesses and employees during lockdown and schemes to promote domestic tourism to reignite the economy after lockdown. The Australia dive industry stakeholder surveys were conducted early in 2021, after the first lockdown, whilst some border restrictions were still in place, which made it difficult to find participants. Two of the four Australia Dive Masters noted impacts due to COVID in the surveys; one mentioned fewer boats and divers and another indicated more “red tape” and getting harder to do the right thing and be financially viable. Interestingly, one commented that COVID might cause more people to look within the state of NSW for diving and one explicitly stated they didn’t close during (the first) COVID lockdown. Two mentioned that whale watching and diversity have contributed to the viability of their businesses in these difficult times. Overall, the Solitary Island dive industry was impacted by COVID-19 but is relatively resilient.

Vietnam reopened its international border in March 2022, two years after it had been closed to foreign travelers (Table 3). Diving activities in Nha Trang attract mainly international tourists. Prior to the Covid-19 outbreak, the majority of foreign visitors to Nha Trang (roughly 70% of all visitors) came from China and Russia (VNExpress, 2018). However, China hasn’t really opened up to allow its citizens to travel abroad until recently. In addition, the prolonged war between Russia and Ukraine made the ruble depreciate, leading to a significant decrease in the number of Russian tourists to Nha Trang as well as Vietnam (VietnamFinance, 2018). Therefore, Nha Trang’s tourism industry has yet to recover from the COVID  19 pandemic. Only a small portion of the scuba diving industry is active; many scuba diving businesses are still closed and unsure of when they will reopen. Of the 24 SCUBA dive companies in Nha Trang that were advertised online before the pandemic, only 8 appear to be active with postings about dive events within the last few months. One company explicitly states that they have now closed due to lack of divers and the others haven’t posted since 2019 or have websites that no longer work.

In Indonesia, international borders were closed for one year, however, there have been lockdowns restricting movement on a local scale in some provinces due to higher and lower infection rates in the population (Table 3). Furthermore, in April 2020, all diving tourism activities were stopped, and people were not able to travel to areas to dive due to a government policy implementing restrictions on community activities in an effort to stop the spread of the corona virus. The dive industry in Maluku province was heavily impacted due to lack of international and domestic tourists and all of the diving centers closed during the ppandemic. However, starting in March 2022, the Indonesian government, eased domestic travel restrictions. Domestic and foreign tourists are now returning, despite the ongoing Covid-19 pandemic. It may take a while for the dive industry to recover in more remote areas like Ambon and Banda Island. However, some of the divers surveyed online did indicate preference for low tourist areas. This could be used as a niche marketing incentive to attract higher paying environmentally aware SCUBA divers interested in a safe diving holiday in a pristine location.

To combat the COVID outbreak, the Malaysia government implemented Movement Control Order (MCO) from March to May 2020 (Table 3). During MCO, any mass gathering and outside movement other than purchasing necessities such as buying food or medicine were prohibited. Further, the MCO was replaced by the Conditional Movement Control Order in June 2020 where the economy was reopened in a controlled manner. However, education sector including universities remained closed in Malaysia. Complete total lockdown was implemented in June 2021 (Table 3) resulting in delaying the project survey. The surveys of dive stakeholders in Malaysia were only able to be conducted in October 2021 after extended total lockdowns had lifted. These surveys asked for pre-Covid responses and did not specifically ask any questions about COVID-19 impacts. None of the Malaysia diver masters mentioned COVID-19, however five out of 9 Dive shop managers identified it as a challenge. The issues identified included travel restrictions on local and international travelers, lack of medical facilities, struggling with unstandardized COVID-19 SOPs, Government intervention and controls, financial struggles and generally struggling to survive the Covid-19 pandemic.

Table 3: Summary of border closures, lockdowns and government assistance in response to the COVID-19 pandemic
Country International border closure Months of local lockdowns Government assistance
Australia1 24 March 2020-March 2022 April – July, 2020 then state/region dependent including Aug-Oct 2021, then state/hotspot dependent. COVID payments for impacted businesses and employees, early access to superfund scheme, regional stimulus packages and free vaccination.
Vietnam March 2020-March 2022 March – April 2020 (countries lockdown), July -September 2021 (local lockdowns). Social security package of up to $US 2.6 billion with specific support for the poor and workers who lost their jobs due to the COVID-19 epidemic. Tax exemption and reduction of fees to support the recovery of businesses, cooperatives and households after the COVID-19 epidemic, support for union members and employees affected by the COVID-19 epidemic.
Indonesia2 2 April 2020-2021 April-June 2020, lockdown in several provinces, then restrictions on community activities and social distancing since January 2021 in hotspots areas to prevent spread. Yes – cash transfers for impacted people, relief in credit payments for informal workers, provide tax incentives and free vaccinations.


Malaysia 18 March 2020 – April 2022 Movement Control Order in March to May 2020, Conditional Movement Control Order from May to March 2021, Total lockdown June 2021. Yes, COVID-19 payments for impacted businesses and employees, bank loan moratorium, educational loan repayments deferred, free vaccination, daily free 1GB internet.

1 Department of Employment and Workplace Relations. COVID-19 timeline. Years, Months, Dates City/Town State/Territory Event Australian Government

2 Ministry of Public Works and Housing of the Republic of Indonesia. Handling the covid -19 pandemic.

The online diver survey was undertaken in early late 2021- early 2022 when some countries were still in lockdown and/or with border restrictions. In response to a question on whether COVID has influenced the way they will choose dive sites in the future, 33 respondents (60%) indicated “yes”, 2 were unsure and 20 indicated “no”. The reasons given by the two indicating ‘no’ were 1) they are vaccinated and don’t go into populated areas anyway and 2) they had decided some years ago to dive locally to reduce their carbon footprint. Of those who indicated yes, the most common reasons were around border or travel restrictions (14) or safety and the risk of infection (13); nine participants identified case numbers in the region and vaccination status of the country and influencing factors; a further four participants identified issues around sanitary measures implemented by the operators. Five participants specifically indicated that they would seek out sites that were less crowded or with fewer divers and/or would avoid sites with mass tourism. Seven participants indicated other issues around travel, including increased costs of travelling and travel insurance and disrupted travel plans. Two participants indicated they were now keen to travel to places they had postponed in the past, whereas another two had reflected on the environmental costs of travel during lockdown and were less likely to travel far. Overall, these insights suggest that there may be increasing demand for boutique diving operations at locations with high quality coral reefs, with few divers and good sanitary methods.


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