The reef manta ray (Mobula alfredi) is a globally threatened species and an iconic tourist attraction for visitors to Komodo National Park, an Indonesian UNESCO World Heritage Site.
The reef manta ray (Manta alfredi) at Dharavandhoo Thila, Maldives. Image credit: Shiyam Elk Cloner / CC BY-SA 3.0.
The reef manta ray is a species of ray in the family Mobulidae, one of the largest rays in the world.
They are typically 3 to 3.5 m in disc width, with a maximum size of about 5.5 m.
First described in 1868 by the Australian researcher Gerard Krefft, they tend to reside and feed in shallow, coastal habitats.
They also visit ‘cleaning stations’ on coral reefs to have parasites, or dead skin picked off by small fish. Courtship ‘trains’ are also observed adjacent to cleaning stations.
In Komodo National Park, manta rays are present year-round, challenging the famous Komodo dragon as the most sought after megafauna for visitors.
“People love manta rays. They are one of the most iconic animals in our oceans,” said Dr. Andrea Marshall, a researcher with the Marine Megafauna Foundation.
“The rise of the number of people engaging in SCUBA diving, snorkeling and the advent of affordable underwater cameras meant that photos and videos taken by the public during their holidays could be used to quickly and affordably scale data collection.”
In their research, Dr. Marshall and colleagues teamed up with the dive operator community serving the Komodo National Park to source identification photographs of manta rays visiting the parks’ waters and submit them to mantamatcher.org, a crowdsourced online database for manta and other rays.
Most of the photographs came from just four locations from over 20 commonly visited by tourism boats.
“I was amazed by how receptive the local dive community was in helping collect much needed data on these threatened animals,” said Dr. Elitza Germanov, a researcher with the Marine Megafauna Foundation, the Centre for Sustainable Aquatic Ecosystems and Environmental and Conservation Sciences at Murdoch University.
“With their support, we were able to identify over 1,000 individual manta rays from over 4,000 photographs.”
The results show that some manta rays moved around the park and others as far as the Nusa Penida MPA (over 450 km to the west), but overall, the animals showed individual preferences for specific sites within the Park.
“I found it very interesting how some manta rays appear to prefer spending their time in some sites more than others, even when sites are 5 km apart, which are short distances for manta rays,” Dr. Germanov said.
“This means that manta rays which prefer sites where fishing activities continue to occur or that are more popular with tourism will endure greater impacts.”
“This study shows that the places where tourists commonly observe manta rays are important for the animals to feed, clean and mate,” said Ande Kefi, an employee of Komodo National Park.
“This means that the Komodo National Park should create measures to limit the disturbance at these sites.”
“I hope that this study will encourage tourism operators to understand the need for the regulations already imposed and increase compliance.”
The findings were published online in the journal PeerJ.
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E.S. Germanov et al. 2022. Residency, movement patterns, behavior and demographics of reef manta rays in Komodo National Park. PeerJ 10: e13302; doi: 10.7717/peerj.1330
Source link: https://www.sci.news/biology/reef-manta-ray-aggregations-komodo-national-park-10813.html
