Tourism has not affected whale sharks at Ningaloo Reef, a five-year study has found.
Even allowing people to swim with the mammals has had no impact, indicating conservation efforts are working, the Australian Institute of Marine Science-University of WA report says.
The number of tourists participating in whale shark activities at Ningaloo Reef has sharply increased from 1000 to 17,000 since 1993 and now generates about $6 million each season.
The research, the first multi-year study on the effects of ecotourism on whale shark populations, found sharks that frequently encountered tourists were just as likely to return to the reef as sharks that little interaction with humans.
"Our research shows that the code of conduct used by the Department of Environment and Conservation to protect whale sharks is very effective with no detectable impacts of tourists on their aggregation behaviour at Ningaloo across years," the report's lead author, Rob Sanzogni, said.
The reef's ecotourism industry was sustainable in its present form.
Kim Hands, development manager at Ecocean, which was involved in developing the code of conduct, said the findings were good news.
She hoped other countries where whale sharks congregated, including Mexico, would adopt similar regulations.
"Obviously, it's been a good model and worked very well as a great example for the rest of the world," she said.
Conservation organisation WWF’s marine spokesman Paul Gamblin said the report was encouraging and showed the industry was receiving appropriate attention but more needed to be done to assist our neighbours, particularly around the Coral Triangle, including Indonesia and the Philippines.
"Australia has played an important role but needs to up the ante to protect the whale sharks when they leave our waters," he said.
"We need to help support local community tourism projects up there because the whale sharks enter more dangerous waters when they leave Australia."
Mr Gamblin said despite the report's positive findings there were still concerns about the impact of resources projects in waters near Ningaloo Reef.
"It increases our concern about the increasing development of the oil and gas industry which is getting ever closer to Ningaloo, including areas where the whale sharks migrate through," he said.
"There's potential for a spill, the impact of very high levels of underwater noise and drilling is something that we should be very concerned about the tourism industry.
"[Protection of whale sharks] is something that obviously needs ongoing vigilance; we can't take our eye off the ball."
The researchers hope the report will provide a blueprint for similar work on the impact of ecotourism on other marine megafauna such as manta rays and whales.