Transcript
AUT PhD researcher Lorenzo Fiori used aerial drones to record whale behaviour inside Vavau's tourist areas to compare them to whales in their uninterrupted state.
He found clear evidence of avoidance.
AUT's Mark Orams, who was involved in the latest Humpback research and with cetacean study in Vava'u since the 1990's, says the industry has grown significantly since that time.
"What's unique about the Tongan situation is that, unlike most other whale watching destinations, they actually allow people to get in the water and snorkel with the whales. And that is often a really wonderful experience for the tourist but does have the potential to disturb what is a really important part of the life cycle of Humpback whales."
Professor Orams is referring to the birthing and bonding of new-born calves with their mothers.
He says tourism has the potential to disturb this fledgling bond.
"They learn most of what they need to know from their mother and so that time, that three to four months they spend after being born, up in those warm tropical waters is a really critical time so something that we need to be really sensitive about in terms of our interest in getting close to the whales."
Mr Orams says increased tour boat activity is forcing mothers to make deep vertical dives to avoid vessels, a tactic which infant calves aren't yet capable of.
He says these longer separation periods between mothers and calves caused by tourism are not necessarily harmful but indicative of something to be concerned about.
One of Vava'u's longer term operators, Vaka and Moana's 'Aunofo Havea Funaki, has said previously it's getting unsustainable.
"What I saw was that too many licences were issued in Vava'u and also too many boats."
There are now over 20 commercial operators taking thousands of tourists out to snorkel close to the whales.
The Tongan government has implemented regulations mitigate negative impacts but Lorenzo Fiori's shows compliance can be poor.
Wait times between tour operators is not being adhered to and minimum distances from the whales is often not being observed.
The Vava'u Environmental Protection Association's (VEPA) Karen Stone says, via email, better policing and compliance are needed through active and methodical monitoring.
"With the current regulations, the legislation as attached has clearly laid out fines for infringements on the law, but without monitoring fines cannot be applied."
AUT's Mark Orams says caution is also needed to mitigate potential effects of human interaction.
"For example, if we are disrupting nursing behaviour, or if we are inducing stress reaction in the targeted whales, then that is something we should probably think about how we can reduce that negative impact because it is such a critical component of their life cycle."
He says the research team will continue to work with the government to help educate operators and increase compliance.
In the meantime, a Vava'u accommodation provider, Vaimalo Fale's Nikki Griffin, says tourists are overwhelmed with the beauty of the interaction and say curious Humpback calves often are the ones who approach.
"The regulations seem to be followed. The guides that they're with, the local guides, care about the environment, care about the interaction with the whales. so, it's just a different perspective from the research."
The Tonga government says it is committed to providing a healthy environment for whales and the tourism sector and is currently reviewing regulations.
It says its taking on board recommendations from the research including limiting operating hours, installing GPS tracking and observers on boats, and declaring a 'no-go' safe zones for nursing mothers.
