Scientists watch Molokini as tourists return | News, Sports, Jobs
Changes in fish populations and behavior were already apparent last week when tour boats and snorkelers returned to Molokini, according to a researcher who has been studying the waters around the crater for 20 years.
“We certainly saw differences between last year and this year – last year there were hardly any boats out; this year, from 18 to 20 boats at peak times ”, said Alan Friedlander, chief scientist for Pristine Seas and the National Geographic Society and director of the Fisheries Ecology Research Lab at the University of Hawaii. “So it looks like it’s back to where it was before, if not more.”
During the first few months of the pandemic, researchers had a unique opportunity to study the Molokini ecosystem without the commercial tours that typically fill the crater off the leeward coast of Maui. A year later, with an increase in visitor arrivals and a busy summer season around the corner, scientists are back in the water to understand the impact of human activity on the marine environment.
Last summer, months after COVID-19 protocols cut off the flow of commercial boats, more fish and bigger predators like ulua, omilu and reef sharks, as well as dolphins and manta rays , had begun to return to the waters off Molokini.
But between April 2020 and this year, there was about a 25% drop in total fish biomass, Friedlander said.
During dives last week, he observed an absence of omilu, sharks and other predators inside the crater.
The fish were seen at the back of the 77-acre crater, which is “In line with what we would expect,” Friedlander said. “These animals are moved from their preferred habitat to another habitat just because of all the people there. Animals definitely react to this.
Friedlander, who is the co-author of five research publications on Molokini conducted in conjunction with the Aquatic Resources Division of the State Department of Lands and Natural Resources, has studied the same sites at Molokini for the past 20 years, witness to a substantial decline. in reef fish populations.
Even though there were no tour boats for a year, private fishing boats and poachers were still spotted in the crater, according to Friedlander and the DLNR.
When commercial activity resumed and visitor arrivals increased, boats could only operate under strict protocols – starting with a maximum capacity of 10 people including crew, then at 50% capacity and now 75%.
“I think what started to happen was that we started to see more and more ships at one point because there was so much demand and the ships couldn’t handle the normal load.” . said Russell Sparks, aquatic biologist with the Maui Aquatic Resources Division. “This could be part of what explains the observations of Alan’s work is that the boats make a lot of noise, they come and go, maneuver and change direction, so having more boats could be worse than have more people.
“Obviously having more people in the water splashing is not good, but what I learned from being there is that the sound of these boats, especially the bigger ones, is considerable.
Molokini is the most visited marine protected area in the world, Friedlander said, attracting around 375,000 people in a regular year, which translates to around 100 people in the water at any given time.
On a positive note, Sparks said the deep waters and strong currents of Molokini help mitigate physical damage to coral reefs or the pollution that settles in the area.
“These are all benefits for Molokini, but I still think we are learning a lot about how intensive human use affects the natural distribution of fish in the area and how this ripples through the webs and the interconnections between these. species ”. he said. “All of this concerns us.”
While Friedlander conducted his annual survey last week of his favorite sites, Sparks and his team surveyed 40 random sites on both shallow and deep reef points in Molokini.
DLNR has been collecting detailed data from marine reserves since 2015, which includes counting fish populations, estimating their size, registering species, counting and quantifying sea urchins and other large invertebrates, the reef health analysis and more.
The two groups compare the results after the data is collected and analyzed.
While research is still ongoing and not all data is ready, Sparks said “I’m pretty sure there is a significant difference” between spring 2020 – when there was no human activity and the number of predatory fish increased – and today.
In the 1970s, Molokini was established as a marine life conservation district due to its “Unique geology and marine life”.
“If you look at the legislation for marine life conservation districts, these are supposed to be the most special places in the state of Hawaii,” Friedlander said. “The main goal is to protect marine life, then it’s access, then it’s trade, and that doesn’t seem to be the way it is now.”
Molokini serves as a connector and resting place between Kahoolawe and Maui when species travel between these islands. Human activity and boat traffic can disrupt their movements, hamper fish reproduction and affect their behavior, he said.
The crater is also of value to local communities and businesses, so better ways of managing the area would help mitigate adverse effects on the marine environment and its resources, he said.
“There has to be that happy medium where people enjoy the place, people enjoy the natural experience, the operators make money, but the resources are healthy and they don’t poach either. a challenge,” Friedlander said.
The bottom line is that people have to recognize that Molokini is a “Very special place, it’s irreplaceable, but it’s also fragile”, he said.
There are currently no restrictions on the number of commercial boats that can be docked at Molokini at one time, according to the DLNR. However, only 40 commercial use permits can be issued for the Molokini Marine Life Conservation District.
DAR aims to review legislation that caps the number of commercial boats at 12 in the crater at the same time once the impacts of the pandemic abate, Sparks said, adding that he understood the challenges this would pose for operations. companies.
“It won’t solve all the problems, but it should help”, he said.
In general, he noted that the boating industry has been “Cooperative and willing to work with us” to find a solution that is both financially efficient and environmentally safe for Molokini.
* Dakota Grossman can be reached at [email protected]