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Marine Life & Conservation Blogs

Creature Feature: Manta Rays

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In this series, the Shark Trust will be sharing amazing facts about different species of sharks and what you can do to help protect them.

This month they’re showcasing the largest rays in the world. Made up of 2 different species, these captivating giants are highly intelligent. And, come in a range of unusual colours!

The word ‘manta’ is Spanish for blanket or cloak, which perfectly describes the body-shape of a manta ray. These enormous, flat, diamond-shaped animals, have wingspans stretching up to 7m wide and can weigh up to 1,350kg.

Mantas also have 2 horns at the front of their head, giving them the nickname ‘devil fish’. But there’s nothing devilish about these gentle giants. Or their close cousins the devil rays, who often get confused for mantas. Both, use their ‘horns’ (or cephalic fins) during feeding to scoop up tiny plants and animals in the water. Similar to how we use a spoon to eat soup. Their cephalic fins may also play a role in sensing their environment and during social interactions.

Just like the Basking and Whale Shark, manta rays are filter feeders. Swimming with their mouths wide open, they suck in huge volumes of water – rich in zooplankton. Their tiny prey is then filtered through gill plates that line their mouth. Sadly, these gill plates are highly sought after in the Chinese medicinal trade, which has led to mantas being heavily over-fished.

As any diver can attest, seeing a manta in the wild is a pure delight. Their elegance and grace in the water is unrivaled. Particularly at feeding time. Mantas need to keep moving to breathe, so individuals will perform multiple somersaults to stay in a single spot where there’s lots of food. Like a perfectly orchestrated dance, mantas will also follow each other in a circle to chain-feed. Their movements expertly creating a vortex that traps their prey inside.

Manta Rays live in tropical, subtropical, and temperate waters around the world. They tend to live on their own or in small groups. But will often gather in large groups to feed. Hotspots for this feeding behaviour include the Bahamas, Fiji, Indonesia, Thailand, Spain and the Maldives. And aggregations are known as a squadron of manta ray.

In 2008, scientists discovered that the Manta Ray, which was once thought of as a single species, was in fact two different species. The Giant Oceanic Manta Ray (Mobula birostris) and the much smaller Reef Manta Ray (Mobula alfredi). Both species were formerly classified under the separate genus Manta. But following genetic testing in 2017, scientists discovered they were more closely related to devil rays (genus Mobula) than previously thought and reclassified them as such.

The Giant Manta is widespread, spending most of their time far from land in open ocean. While the Reef Manta tends to prefer the warmer coastal waters of the Indo-Pacific. Fully grown, the wingspan of a Giant Manta can reach up to 7m (typically 4.5m). While the largest wingspan for a Reef Manta is 5m (typically 3-3.5m). Both are dark in colour on top with a pattern of white lines. On the Giant Manta the white lines form a T shape, while on the Reef Manta they form a Y shape.

We can also identify each individual manta by their unique markings. Found on the underside of their body (between the gills and on their bellies), these act just like a human fingerprint. Enabling scientists to use photo-ID to discover more about them.

Manta Rays regularly visit cleaning stations, like many other marine animals, often returning to the same spot. Here smaller animals groom them, removing pesky parasites and dead skin. These spa trips to the coral reef provide researchers with the perfect opportunity to photograph and study them in the wild.

In Raja Ampat, researchers have discovered an unusual group of Reef Mantas, affectionately known as the ninja warriors. This area has the highest percentage of melanistic (black) Reef Mantas in the world. Usually melanistic mantas comprise around 10% of a population, but here they represent 40%. This genetic trait is inherited and doesn’t appear to affect their survival rate.

If you visit the Great Barrier Reef, you may witness an even more astounding sight…

A 3m male Reef Manta named ‘Inspector Clouseau’, who also happens to be bright PINK! Big thanks to Kristian Laine Photography for providing the incredible photo above.

The Inspector is the only known pink manta in the world. His rosy hue is believed to be the result of a condition called erythrism – a genetic mutation in melanin production. Again, this doesn’t seem to impact his survival. Indeed, he’s been spotted a handful of times since his first debut in 2015, so is doing well.

Highly intelligent, these majestic animals have the largest brain to body weight ratio of any fish. Studies suggest they have high cognitive function – similar to dolphins, primates and elephants – and excellent long-term memory.

Due to their large size, adult mantas don’t have many natural predators. Although, larger sharks and orca have been known to prey on them. Yet, the biggest threat they face comes from humans. Due to their low reproductive rate mantas are incredibly vulnerable to over-fishing.

These long-living animals are thought to live up to 50 years. Giving birth every 4-5 years, they’ll only produce between 4-7 pups during their lifetime.


GIANT MANTA RAY:

  • SCIENTIFIC NAME: Mobula birostris
  • FAMILY: Mobulidae (Manta & Devil Rays)
  • MAXIMUM SIZE: 7m
  • DIET: Zooplankton, krill & small fish.
  • DISTRIBUTION: Worldwide in tropical and temperate waters. Found from the surface to depths of 1,000m.
  • HABITAT: Spends long periods of time in the open ocean. Visits shallow coastal waters near coral and rocky reefs.
  • CONSERVATION STATUS: Endangered

REEF MANTA RAY:

  • SCIENTIFIC NAME: Mobula alfredi
  • FAMILY: Mobulidae (Manta & Devil Rays)
  • MAXIMUM SIZE: 5m
  • DIET: Zooplankton, krill & small fish.
  • DISTRIBUTION: Tropical and sub-tropical waters of the Indian and Pacific Ocean. Found from the surface to depths of 432m.
  • HABITAT: Shallow coastal waters near coral and rocky reefs. Moves into deeper waters at night to feed.
  • CONSERVATION STATUS: Vulnerable

Header Image: Frogfish Photography

The Shark Trust is the leading UK-based shark conservation charity. The team works globally to safeguard the future of sharks, and their close cousins, the skates and rays. Engaging with a global network of scientists, policymakers, conservation professionals, businesses and supporters, to further shark conservation. Established in 1997 to provide a voice for UK sharks, the Shark Trust has an ever-growing number of passionate supporters. And together we're creating positive change for sharks around the world. Want to join us and help protect sharks around the world? Click here! www.sharktrust.org

Marine Life & Conservation

Top 5 Party Guests: The Magic of Night Diving in Cozumel

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A blog by Pro Dive International

*Header image: On the day of our planned night dive at the Allegro Cozumel, we had to reschedule, as any water activity during thunderstorms and lightning is considered dangerous. We still thought it was worth sharing this breathtaking spectacle with you.*


Have you ever gazed out at the open ocean at night wondering what happens down there as the sun disappears over the horizon and darkness sets in? If all marine life will be sleeping, or if there’s anything creeping along the reefs?

Here’s what really happens, including a list of our Top 5 Party Guests that make you want to add night diving in Cozumel to your bucket list.

Brief Overview

While the Caribbean Sea is not calming down at night due to the effectively constant trade-winds in the tropics that drive ocean wave trains and cause waves to break throughout day and night, a vibrant party under the sea is just about to begin, as huge basket stars unfurl their arms into the night, parrotfish create their mucus bubble beds, giant lobsters, king crabs and octopus prepare for hunt, and bioluminescence sparkles up the scene.

TOP 5 Party Guests

1. Basket Stars

These sea stars can only be observed in their true glory at night when they unfurl their many branched arms into the darkness to filter food from the water. Some reach nearly a meter in size! Shine your torch on them and watch them curl their huge arms back towards their mouths as they eat the small creatures attracted by your light. 

The perfect party costume, do you agree?

Basket Star by Elizabeth Maleham @Pro Dive International

2. Cephalopods – Octopus & Squid

These fascinating creatures are rarely spotted during day dives, but at night you can see them out and about hunting the reef for their next meal. Watch as they move about changing colors and patterns in the blink of an eye! Below is a picture of an octopus spreading its body wide over the reef like a net to encircle its prey.

Did you know that octopuses were that colorful?

Octopus by Elizabeth Maleham @Pro Dive International

3. Crustaceans

Safely tucked away in the back of a crevice during the day, these creatures venture out under the cover of darkness to hunt. A fantastic opportunity to finally get a close-up look at all those king crabs and plenty of lobsters you have only seen as small eyes peering out from the back of a cave.

Up for a dance?

Crab by Elizabeth Maleham @Pro Dive International

4. Parrotfish

Many fish only half sleep, needing to be alert to the dangers 24/7, but parrot fish have evolved an ingenious warning system so they can get their eyes shut. As night draws in, they find a nook to rest in and start to create a mucus like a bubble encircling their whole bodies. They can rest safely in this for the entire night, but if anything disturbs this veil, they are off like a shot into the dark!

How did this sleepy guy make it into our Top 5?

Parrotfish in Cozumel by Guillermo Reta @Pro Dive International

5. Bioluminescence

For those not familiar with this natural phenomenon, bioluminescence is a chemical process which allows living creatures like plankton, tiny crustaceans, some fish, squid and algae to produce light in their body to either attract prey, confuse predators, or lure potential mates.

As the bioluminescent sea will glow when it’s disturbed by a breaking wave or a splash in the water at night, for most of our divers the best part is covering up the torches and waving our arms about disturbing the bioluminescence into sparkling blue points of light. 

This makes the perfect party glitter!

Bioluminescence @Dreamstime


Already in a party mood? Pack your dive gear!

How to join the underwater party in Cozumel?

  1. Join Pro Dive International’s Cozumel Night Dives as a certified diver.
  2. Boost your skills and make your night dive one of the 5 Adventure Dives of the PADI Advanced Open Water Diver course.
  3. Contact us for guidance.


Contact:

reservations@prodiveinternational.com 

www.prodiveinternational.com/contact-us

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Marine Life & Conservation Blogs

8 Places to Seek Adventure with Octopus

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A Guest Blog by PADI.com

World Octopus Day on 8 October 2021 highlights the need to continue to explore and protect the ocean so that the 300 recognized species of octopus can continue to live in rock formations, coral reefs and throughout the seas.

Octopus have long been one of the most fascinating marine encounters to have as a diver. With three hearts, blue blood, the ability to camouflage on demand and their high levels of intelligence, these curious creatures place high on many divers’ bucket lists.

They can be found in a range of ocean climates around the globe, making diving with octopus attainable worldwide.

Here are eight of some of the best places to dive with octopus:

1. Canary Islands

Offering warm and clear water all year round, the Canary Islands off the northwest coast of Africa and the eastern edge of the Atlantic Ocean are a great place to dive with octopus, who are often hiding under the rocky terrain below the surface.

2. The Maldives

This low-lying nation offers white sand beaches, vibrant coral reefs and plenty of opportunity to dive with octopus. The rich water in the Maldives feed the soft coral that clings to rock slides, providing a range of locations for octopus to build their home. They are a common sighting there amongst those who both snorkel and dive.

3. French Polynesia

Octopus are an essential part of French Polynesian culture—they have an octagonal building referred to as the “Octopus Church” on the island of Mo’orea and the island archipelago is home to the Micronesia mythology octopus god referred to as Na Kika. Beneath the surface of these low-lying atolls in French Polynesia are marine creature clusters that often include octopus hiding amongst the rocks or coral beds.

4. South Africa

This destination put diving with octopus on the top of the list for many after last year’s release of the Netflix documentary My Octopus Teacher. False Bay near Cape Town, as highlighted in the film, is one location to dive with octopus. But the varied climates and currents provide a range of opportunities for close encounters with these marine creatures across the coastline.

5. Indonesia

As the epicenter of biodiversity beneath the surface of Indonesia’s waters, octopus are just one of the many marine animals that call this collection of 17,508 islands home. Lembeh Strait is often full of various species, including the mimic octopus, who can change into and act like a variety of other marine species like lionfish and sea snakes.

6. Philippines

The Philippines offers divers thousands of dive sites to choose from. But those wanting to dive with an octopus should plan a visit to the Sea Explorers House Reef in Dauin, where blue ring octopus are known to be found during the month of October, often amongst the colorful soft coral.

7. United States

Off the California coastline are thousands of tidepools that offer a sanctuary for octopus and a great place for those with their fins off to have an encounter with them. Those wanting to dive deeper can do a shore dive at Shaw’s Cove in Laguna Beach, where octopus are known to hang out around the underwater statue dubbed Shelley of Shaw’s. And farther North up the Pacific Coast off the shores of Washington, divers can encounter giant Pacific octopus in the waters of Olympic National Park.

8. Australia

For those wanting to find the world’s smallest octopus, the blue ring octopus can be found off the coast of Sydney and Melbourne in Australia. This tiny octopus is known for its beautiful blue marking and will flash bright blue and black rings to warn predators to stay away. The world’s smallest octopus is also the most venomous, so make sure to admire them from a safe distance.

To explore these dive sites and more, get in touch with your local PADI Dive Center or Resort and become a PADI Open Water Diver.  And for those wanting to help protect octopus, other marine species and the ocean they call home, join the community of PADI Torchbearers to learn more about how to get involved and help restore ocean health.


Photo credit – Annie Crawley, PADI AmbassaDiver and Master Scuba Diver Instructor / @anniecrawley_oceanannie

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Our special, extended, 14 night charter of MV Carpe Diem in the Maldives will visit some of our favourite sites in the central and near-south atolls. We will be spending 14 nights on-board, specifically because we want to travel and have time to enjoy the sites without rushing too much.

The boat will depart from Male on Saturday 23rd October and guests will disembark on Saturday 06th November. The route will incorporate our favourite manta points, shark diving points and spectacular coral reefs.

 

Please contact us for last minute prices on 01473921888 or email us at info@greatescapesdivingholidays.com

 

 

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