Connect with us
background

News

Tourists key to future of rare manta nursery

Published

on

Scientists from the Marine Megafauna Foundation and Murdoch University are reporting a large number of juvenile manta rays in the waters of Nusa Penida, a small island 18km southeast of Bali, suggesting the area may be a nursery for this threatened species.

Reef mantas (Mobula alfredi), which grow up to 5m, 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. In Nusa Penida, they are present year-round making the Marine Protected Area (MPA) a snorkeling and diving hotspot.

One of the popular dive sites (Manta Bay) described in this new study is predominantly frequented by juvenile males looking for food. Some are as small as 1.5m in disc width on first sighting, providing strong evidence that the site forms part of a nursery habitat and foraging ground for the local reef manta population. Most individuals have been seen repeatedly across multiple years.

Image: Simon Pierce (www.simonpierce.com)

Where manta rays are born and grow up still baffles us. Our research in Indonesia suggests there might be a reef manta nursery in the Nusa Penida area and possibly also in the famous Raja Ampat archipelago”, said lead author Elitza Germanov. “It’s really important for us to know where these nurseries are. They provide a safe space for young, vulnerable manta rays to grow and develop away from the reach of predators.”

Interestingly, mature males and females seem to prefer Manta Point, a second dive site a mere 12 km away. Here, the manta rays are mostly observed visiting cleaning stations and engaging in social activity as well as courtship display during the mating season (peaking in May).

Nusa Penida attracts more than 200,000 tourists each year. Of the 11 main dive spots in these waters, Manta Bay and Manta Point are frequented most by tourism operators, putting the local manta ray population under increasing pressure. While manta rays are protected in Indonesia2, there are currently few regulations in place to manage the growing tourism industry. The number of boats allowed to enter manta ray habitats is not limited and codes of conduct for manta ray interactions are voluntary. The average annual number of boats present at the two manta ray sites has increased by 60% since 2012 and tourism is highest during the mating season.

Germanov commented: “Large diving groups and boat engine noise can cause chronic stress to these vulnerable animals. Tourists may disrupt the foraging, cleaning and mating behavior of manta rays if they get too close, which can have serious implications for their growth and fitness.”

Limiting the number of tourism vessels allowed at one time and making codes of conduct for diving and snorkeling with manta rays mandatory are proposed as a way to minimize the impact from tourism. Seasonal closure of Manta Point could also be considered to protect the manta rays from disturbance during the mating period.

Artisanal fishing poses a further threat to the local population. During the study, 14% of manta rays were either trailing hooks and lines or had injuries and even amputations from fishing gear cutting through their skin and cartilage skeleton. While all fishing activities are officially prohibited in both Manta Bay and Manta Point, the whole west coast of Nusa Penida could be closed off as a precautionary measure.

Dr Andrea Marshall, principal scientist and co-founder of the Marine Megafauna Foundation said: “This is clearly an important habitat for reef mantas. In fact, the resighting rates in the Nusa Penida MPA are higher than anywhere else in the world.

“The two aggregation sites are very close to each other but used for different purposes. We still don’t know much about when and how the mantas move between the feeding, cleaning and mating grounds. Putting the pieces of this puzzle together will help us figure out how to protect these slow-growing animals.

For more information about the work of the Marine Megafauna Foundation visit their website by clicking here.

Blogs

Northern Red Sea Reefs and Wrecks Trip Report, Part 2: Wall to Wall Wrecks

Published

on

red sea

Jake Davies boards Ghazala Explorer for an unforgettable Red Sea diving experience…

The second day’s diving was a day full of wreck diving at Abu Nuhas, which included the Chrisoula K, Carnatic, and Ghiannis D. The first dive of the day was onto the Chrisoula K, also known as the wreck of tiles. The 98m vessel remains largely intact where she was loaded with tiles which can be seen throughout the hold. The stern sits at 26m and the bow just below the surface. One of the highlights of the wreck is heading inside and seeing the workroom where the machinery used for cutting the tiles are perfectly intact. The bow provided some relaxing scenery as the bright sunlight highlighted the colours of the soft coral reef and the many reef fish.

red sea

Following breakfast, we then headed to the next wreck, which was the Carnatic. The Carnatic is an 89.9m sail steamer vessel that was built in Britain back in 1862. She ran aground on the reef back in 1869 and remains at 27m. At the time, she was carrying a range of items, including 40,000 sterling in gold. An impressive wreck where much of the superstructure remains, and the two large masts lay on the seafloor. The wooden ribs of the hull provide structures for lots of soft corals, and into the stern section, the light beams through, bouncing off the large shoals of glass fish that can be found using the structure as shelter from the larger predators that are found outside of the wreck.

red sea

The final wreck at Abu Nuhas was the Ghiannis D, originally called ‘Shoyo Maru,’ which was 99.5m long and built in Japan back in 1969 before becoming a Greek-registered cargo ship in 1980. The ship then ran aground on the reef on April 19th, 1983, and now sits at the bottom at a depth of 27m. Heading down the line, the stern of the ship remains in good condition compared to the rest of the hull. The highlight of the wreck, though, is heading into the stern section and down the flights of stairs to enter the engine room, which remains in good condition and is definitely worth exploring. After exploring the interior section of the ship, we then headed over to see the rest of the superstructure, where it’s particularly interesting to see the large table corals that have grown at the bow relatively quickly considering the date the ship sank. After surfacing and enjoying some afternoon snacks, we made sure everything was strapped down and secured as we would be heading north and crossing the Gulf of Suez, where the winds were still creating plenty of chop.

red sea

The next morning, it was a short hop to Ras Mohammed Nature Reserve for the next couple of days of diving. The 6am wake-up call came along with the briefing for the first site we would be diving, which was Shark & Yolanda. The low current conditions allowed us to start the dive at Anemone City, where we would drift along the steep, coral-filled wall. These dives involved drifts, as mooring in Ras Mohammed wasn’t allowed to protect the reefs. As a dive site, Shark & Yolanda is well-known and historically had a lot of sharks, but unfortunately not so many in recent years, especially not so early in the season. However, there was always a chance when looking out into the blue.

red sea

The gentle drift took us along the steep walls of the site, with plenty of anemone fish to be seen and a huge variety of corals. It wasn’t long into the dive before we were accompanied by a hawksbill turtle, who drifted with us between the two atolls before parting ways. Between the two reefs, the shallow patch with parts of coral heads surrounded by sand provided the chance to see a few blue-spotted stingrays that were mainly resting underneath the corals and are always a pleasure to see. With this being the morning dive, the early sunlight lit up the walls, providing tranquil moments. Looking out into the blue, there was very little to be seen, but a small shoal of batfish shimmering underneath the sunlight was a moment to capture as we watched them swim by as they watched us.

red sea

Towards the end of the dive, we stopped at the wreck of the Jolanda where the seafloor was scattered with toilets from the containers it was carrying. This provided a unique site to make a safety stop, which was also accompanied by a large barracuda slowly swimming by, along with a hawksbill turtle calmly swimming over the reef as the sun rays danced in the distance.

For the next dive, we headed north to the Strait of Tiran to explore the reefs situated between Tiran Island and Sharm El Sheik, which were named after the British divers who had found them. We started on Jackson before heading to Gordons Reef, where we also did the night dive. All the atolls at these sites provided stunning, bustling coral reefs close to the surface and steep walls to swim along, which always provided the opportunity to keep an eye out for some of the larger species that can be seen in the blue. Midwater around Jackson Reef was filled with red-toothed triggerfish and shoals of banner fish, which at times were so dense that you couldn’t see into the blue. Moments went by peacefully as we enjoyed the slow drift above the reef, watching these shoals swim around under the mid-afternoon sun.

red sea

The night dive at Gordon’s Reef was mainly among the stacks of corals surrounded by sand, which was great to explore under the darkness. After some time circling the corals, we came across what we were really hoping to find, and that was an octopus hunting on the reef. We spent the majority of the dive just watching it crawl among the reef, blending into its changing surroundings through changes in colour and skin texture. It’s always so fascinating and captivating to watch these incredibly intelligent animals, in awe of their ability to carry out these physical changes to perfectly blend into the reef. Before we knew it, it was time to head back to the boat to enjoy a well-deserved tasty dinner prepared by the talented chefs onboard.

Check in for the 3rd and final part of this series from Jake tomorrow!

To find out more about the Northern Red Sea reef and wrecks itineraries aboard Ghazala Explorer, or to book, contact Scuba Travel now:

Email: dive@scubatravel.com

Tel: +44 (0)1483 411590

www.scubatravel.com

Photos: Jake Davies / Avalon.Red

Continue Reading

Marine Life & Conservation

Double Bubble for Basking Sharks

Published

on

The Shark Trust is excited to announce that, for two more days only, all donations, large or small, will be doubled in the Big Give Green Match Fund!

Donate to Basking in Nature: Sighting Giants

The Shark Trust is hoping to raise £10k which will be doubled to £20k. This will go towards Basking in Nature: Sighting Giants. And they need YOUR help to reach they’re goal.

The Shark Trust’s citizen science project is to monitor and assess basking sharks through sightings; encouraging data collection, community engagement, and promoting nature accessibility. This initiative aims to enhance health and wellbeing by fostering a deeper connection with British Sharks.

Campaign Aims

  • Increase citizen science reporting of Basking Sharks and other shark sightings to help inform shark and ray conservation.
  • Provide educational talks about the diverse range of sharks and rays in British waters and accessible identification guides!
  • Create engaging and fun information panels on how to ID the amazing sharks and rays we have on our doorstep! These can be used on coastal paths around the Southwest. With activities and information on how you can make a difference for sharks and rays!
  • Promote mental wellbeing through increasing time in nature and discovering the wonders beneath the waves!

Donate, and double your impact. Click Here

Continue Reading

E-Newsletter Sign up!

Experience the Red Sea in May with Bella Eriny Liveaboard! As the weather warms up, there’s no better time to dive into the crystal clear waters of the Red Sea. Join us on Bella Eriny, your premier choice for Red Sea liveaboards, this May for an unforgettable underwater adventure. Explore vibrant marine life and stunning coral reefs Enjoy comfortable accommodation in our spacious cabins Savor delicious meals prepared by our onboard chef Benefit from the expertise of our professional dive guides Visit our website for more information and to secure your spot: www.scubatravel.com/BellaEriny or call 01483 411590 More Less

Instagram Feed

Popular