Hawaii shark-tour visitors were still doing more for sharks two years later
University of Sydney researchers estimate that Oahu shark-tour participants were 40% more likely to act for sharks two years later than without the tour. With a Waikiki Beach comparison group, the result is firmer on a lasting difference than on what the tour caused.
The Scientist · Science desk
Per the University of Sydney study, tour participants were 40% more likely to be engaging in shark conservation behavior two years on than expected without the tour. Over 500,000 people a year are estimated to join shark and ray eco-activities, offered in at least 20 countries.
| Figure | Value | Note | Claim |
|---|---|---|---|
| More likely to act for sharks two years on, per study | 40% | 3 | |
| Participants a year, over | 500,000 people, est. | in shark and ray eco-activities | 9 |
| Countries, at least | 20 countries | offering shark and ray eco-activities | 9 |
What happened
- Both cohorts came from Hawaii: tourists on an Oahu snorkeling or freediving shark tour, and a comparison sample of the public drawn on Waikiki Beach.
- Both groups answered a survey when the tour took place and a second one two years on, asking whether they had taken part in any shark conservation activity.
- Activity rose in both groups, more among tour participants, and the gap held after adjusting for demographics, prior conservation involvement and attrition.
- Among tour participants the biggest increases were in social media posts, petition signing, donations and advocating for legislation.
Why it matters
- constraint Operators and funders cannot yet say how much of the effect comes from the swim and how much from the biologist's teaching, because the tour delivered both together.
- decision Anyone citing the result for the whole industry is stretching one Oahu tour format across at least 20 countries, and should cite it for tours built like that one.
- constraint The outcome is reported behavior, so the study cannot show that the petitions, donations or posts changed shark numbers.
The 40% is a relative figure. It compares tour participants with what would be expected of them had they not taken part [3], and the write-up does not report the baseline rate, the number of people surveyed or the attrition between surveys. Without those, the figure cannot be converted into a count of people who signed, donated or posted.
The comparison group is the part to read closely. People who sign up for an in-water shark encounter may already care more about sharks than a typical beachgoer does. The researchers adjusted for demographics, prior involvement in conservation and attrition [7], which covers the differences they measured. In our view that leaves open how much of the gap reflects who books such a tour.
The tour was also a package. The marine biologist on board surveyed the sharks for ongoing research and gave educational information about shark conservation [5]. With two groups, the study cannot say how much of the effect comes from the encounter and how much from the teaching. Lead author Carmen Dobszewicz said: "Supplementing the underwater experience with educational information on the role sharks play in the ecosystem, the threats they face and what can be done to mitigate these threats leaves tourists with a better understanding of the precarity of shark populations and what we can do to try and rebuild them." [13]
The industry claim needs narrowing. According to the University of Sydney, the findings, together with a recent positive shift in news and online sentiment toward sharks, suggest the benefits of shark tourism are more than economic [14]. The study followed tourists on one Oahu tour [4]. The activity it is cited for draws more than 500,000 people a year in at least 20 countries [9]. Dobszewicz tied her own conclusion to a narrower group: "Our findings suggest responsible tour operators can be a much-needed boon to efforts to halt the rapid decline in shark populations and help shift widely held misconceptions about sharks," she said. [12]
The claim of a commitment lasting at least two years [2] rests on two survey waves, one at the tour and one two years on [6]. They show a difference at the second wave. They do not show a continuous run of activity in between.
We think the data support a statement narrower than the industry-wide one: a biologist-led, education-heavy tour in Hawaii went with lasting extra advocacy among its visitors.
The thing this doesn't tell you is whether any of that activity helped sharks. The outcome measured is what respondents reported doing. Shark populations have fallen 71% over 50 years, and a third of species are threatened with extinction [10].
What to watch
- The paper's own tables: sample sizes and baseline rates would turn the 40% into a count of people.
- A replication outside Hawaii, or one comparing tour-goers with people who inquired about a tour but did not go.
- A trial that varies the education component while holding the in-water encounter fixed.
Clarity's read
What the record supports and how the coverage leans. The claims behind it follow.
Reality
- Evidence55
- Adoption
- Insufficient
- Hype gap+20
- Incentives
- Insufficient
- Confidence50
Claim ledger
Ranked by verification strength, evidence, and original report placement.
- [1]
New University of Sydney research shows people who join shark ecotourism tours are more likely to take action to protect sharks, including donating, signing petitions or speaking up online.
- [2]
The study is described as the first to demonstrate a commitment to conservation lasting at least two years among shark ecotourists.
- [3]
Two years after their tour, participants were 40% more likely to be engaging in shark conservation behavior than would be expected had they not taken part.
- [4]
The researchers surveyed two cohorts, both drawn from Hawaii: tourists on an experiential shark ecotourism tour on Oahu who snorkeled or freedived with sharks, and a comparison group of members of the public sampled from Waikiki Beach.
- [5]
On the tour, participants were accompanied by a marine biologist who surveyed the sharks to support ongoing research and provided educational information about shark conservation.
- [6]
Each group was surveyed at the time of the tour and again two years later, and on each occasion respondents were asked whether they had engaged in shark conservation activities.
- [7]
Conservation activity increased in both groups over the two years, but the rise was considerably larger among tour participants, and this held after accounting for differences between the groups at the start, including demographic traits, prior involvement in conservation and attrition rates between the two surveys.
- [8]
Among tour participants, the biggest increases were in posting on social media, signing petitions, making donations and advocating for legislation.
- [9]
More than 500,000 people a year are estimated to participate in interactive eco-activities with sharks and rays, offered in at least 20 countries.
- [10]
Globally, shark populations have declined by 71% in the last 50 years, with a third of species now threatened with extinction.
- [11]
The research was published in npj Ocean Sustainability and led by University of Sydney Ph.D. candidate Carmen Dobszewicz.
- [12]
"Our findings suggest responsible tour operators can be a much-needed boon to efforts to halt the rapid decline in shark populations and help shift widely held misconceptions about sharks," Dobszewicz said.
- [13]
"Supplementing the underwater experience with educational information on the role sharks play in the ecosystem, the threats they face and what can be done to mitigate these threats leaves tourists with a better understanding of the precarity of shark populations and what we can do to try and rebuild them."
- [14]
Coupled with a positive shift in news media and online sentiment toward sharks in recent years, the findings suggest the benefits of the burgeoning industry are more than economic, offering the potential to help conserve dwindling shark numbers.
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Sources
1 independent publisher whose own reporting we read for this story.
- phys.orgHow shark ecotourism sparks long-term conservation
1 article · October 14, 2026
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