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Just like a snowflake falling from the sky, the whitespotted eagle ray is unique; no two are exactly the same. The whitespotted eagle ray is a beautiful sight to behold with its long pointy tail and its body spotted with white dots.

The whitespotted eagle ray (Aetobatus narinari) is a cartilaginous fish—and one of the ocean’s largest rays. The genus name Aetobatus comes from the Greek word aetos meaning “eagle” and batis meaning “ray.”

Habitat and Size

Whitespotted eagle rays can be found swimming in tropical to warm temperate waters in the Atlantic. They are easy to spot because of their spotted bodies—and they are favorites for ocean photographers and scuba divers to witness.

The whitespotted eagle ray spends most of its time gliding through the open ocean. But they can also be found in coastal environments such as coral reefs, estuaries and bays. In the open ocean, whitespotted eagle rays usually swim in large schools towards the surface of the ocean. That would be a wonderful sight to see! They are also known to swim long distances.

Whitespotted eagle rays are massive in size—they have a wingspan of up to 10 feet and can weigh up to 500 pounds! If you were to measure one, from the tip of the snout to the tip of the tail, you would find that it could be as long as 16 feet. Female whitespotted eagle rays tend to be larger than the males.

Physical Appearance

When looking at a whitespotted eagle ray, you’ll notice that the snout looks similar to a bird’s beak—which is exactly how the whitespotted eagle ray got its name. Their unique-looking snouts work to their advantage. While looking for food, they use their snouts to investigate and dig around in the sand for something delicious to eat. Their mouths contain flat plates of teeth which are used to crush their food—the hard shells of crustaceans and mollusks.

Like a snowflake or human fingerprint, each whitespotted eagle ray has a unique pattern of spots. The top of the body is a darkish brown or black with white circles. The bottom of the body is whiteish.


Fun Facts About Whitespotted Eagle Rays

  • A group of rays is called a “fever of rays.”
  • In the animated Disney movie Finding Nemo, Nemo’s schoolteacher, Ray, is an eagle ray. Do you remember the song Ray sang to the students?

Venomous Tail Spines

The whitespotted eagle ray is shy and non-aggressive. However, it is still considered dangerous to humans because of its venomous tail spines which can cause some serious wounds. The whitespotted eagle rays use their tails, which may have two to six venomous spines at the base, for self-defense.

Flying and Jumping

Whitespotted eagle rays have occasionally been known to leap completely out of the water! Scientists don’t really know why they jump and leap. They think this unusual movement could be a mating ritual, an effort to escape predators, a way to communicate with other rays or a method to help remove parasites.

Diet and Reproduction

The whitespotted eagle ray, like other sharks and rays, has an electrosensory system consisting of hundreds of electroreceptive organs, referred to as the ampullae of Lorenzini. These organs help them sense other organisms hiding behind coral or buried in the sand. They are predators and use the ampullae of Lorenzini to detect prey and prepare for an attack. They enjoy eating mollusks, oysters, shrimp, crabs, octopus, worms, whelks and small fishes.

Regarding reproduction, whitespotted eagle rays are ovoviviparous. This means they reproduce via internal fertilization. The female incubates the eggs internally where they hatch. Then, the female gives birth to live pups.

Whitespotted eagle ray swims in ocean

Age and Population Status

The lifespan of a whitespotted eagle ray is about 15 years, but they can live to 20 years or more.

Whitespotted eagle rays are listed as “Endangered” on the Red List of Threatened Species of the International Union for the Conservation of Nature (IUCN). Their populations are declining throughout the world, with fishing being one of the main threats. They are directly targeted in some places around the world and caught as bycatch in other fisheries. They are also threatened by pollution, habitat loss and impacts from climate change.

How You Can Help Whitespotted Eagle Rays

It’s up to all of us to help protect whitespotted eagle rays, coral reefs, the open ocean and all the animals living in the sea. Ocean Conservancy is working with you to protect the ocean from today’s greatest global challenges. Together, we create evidence-based solutions for a healthy ocean and the wildlife and communities that depend on it.

Please make a donation to Ocean Conservancy—give today and make a difference for the future of our ocean!

The post All About Whitespotted Eagle Rays appeared first on Ocean Conservancy.

All About Whitespotted Eagle Rays

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Ocean Acidification

The Mysteries of the Mariana Trench

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Our ocean is an incredibly vast and mysterious place. And there is no place where that is more evident than the deepest ocean area in the world: the legendary Mariana Trench. Located east of the Philippines, the Mariana Trench lies in the Mariana Archipelago in the western portion of the North Pacific. The greater area of the Mariana Trench Marine National Monument is made up of more than 95,000 square miles of ocean. Beneath these waters lie incredibly complex aggregations of submerged islands and volcanoes … and of course, an astoundingly massive trench.

Dive in with us to have your biggest questions answered about the famed Mariana Trench.

How deep is the Mariana Trench?

The deepest part of the Mariana Trench, known as Challenger Deep, is almost 36,000 feet below the ocean’s surface. For context, Mount Everest is about 29,000 feet above sea level, so the Mariana Trench is about 7,000 feet deeper than Mount Everest is tall. For one more comparison, the RMS Titanic lies at a depth of about 12,500 feet below sea level. The Challenger Deep is in waters nearly three times deeper than this ship’s final resting place.

Due to its enormous size, the Mariana Trench has at times been affectionately nicknamed the Grand Canyon of the ocean. This is certainly a picturesque image, but don’t let the mammoth size of this U.S. national terrestrial park fool you into thinking the Mariana Trench matches its size. The trench’s footprint is estimated to be 120 times larger than the Grand Canyon’s, and to reach the bottom of Challenger Deep, you’d need to descend through almost six Grand Canyons stacked on top of each other before you’d reach the seafloor.

Oh … and did we mention it’s five times wider than it is deep? It’s about 43 miles wide!

What is Challenger Deep, and how long would it take to reach it?

Challenger Deep is the deepest point of the Mariana Trench. Fewer than 30 people have ever journeyed to this area. The trek below the surface is long, dark and time-consuming, and it’s not an expedition considered lightly by scientists and explorers.

The first people to descend into the depths of this area in 1960 were oceanographers Jacques Piccard and Don Walsh, and it took them close to five hours to reach Challenger Deep. Since then, more advanced submersibles have been created, but it still takes two to four hours for modern vessels to reach such depths. For example, explorer and filmmaker James Cameron reached the seafloor in a little more than 2.5 hours in the first documented solo submarine dive to the area, and it took oceanographer Dr. Dawn Wright about four hours in 2022. It is crucial that these submersibles descend slowly and steadily beneath the surface, as the immense water pressure compounds with every mile a submersible descends. Speaking of pressure …

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What is the water pressure at the bottom of the Mariana Trench?

If you thought the depth of the Mariana Trench was its only jaw-dropping feature, think again. Water pressure is one of the most important factors affecting deep-sea life. In the ocean, pressure increases by one atmosphere for every 33 feet (10 meters) of depth. One atmosphere (a unit of measurement for pressure equivalent to average air pressure at sea level) is equal to about 14.7 pounds per square inch (PSI), which is the approximate standard atmospheric pressure at sea level. If you were to convert atmospheric pressure into weight, one atmosphere is about the weight of a bowling ball. Stay with me, friends.

If a vessel were to dive 2,000 feet below the surface, the pressure would equal that of 60 bowling balls stacked atop every square inch of that submersible. But 60 bowling balls is simply nothing compared to the pressure in the Mariana Trench. The atmospheric pressure at the depths of Challenger Deep is equal to about 16,000 PSI. That pressure is about the same as the weight of an entire full-grown elephant on every square inch of a submersible!

Need a more extreme comparison? If a human were to be placed at the bottom of the Mariana Trench, the pressure would be equal to that of 50 jumbo jets piled on top of a person!

Do any animals live in the Mariana Trench?

The depths of the Mariana Trench come with immense pressure and extreme darkness, but somehow, life finds a way to survive. Organisms that live at an extreme depth, like that of Challenger Deep, have to be highly adapted to low temperatures (typically just above freezing), high pressure and virtually no light at all.

Species found in the depths of the Mariana Trench might look vastly different from animals from other ocean depths because their anatomy has been refined to thrive in harsh conditions. At such great depths, these animals typically depend on chemosynthesis (using nutrient-rich waters being pumped out of hydrothermal vents) or descending detritus (dead matter that has fallen from higher parts of the ocean) for food, such as whale falls. Just a handful of these animals include species of octopuses and squids, sea cucumbers, amphipods, sea jellies, shrimp, sea worms and some wild-looking fish!

In 2025, more than 7,000 new species were discovered in the Mariana Trench, including the hadal snailfish (Pseudoliparis swirei). This is the deepest-dwelling fish currently known to science. Now, the fish has been dubbed “the Mariana snailfish.”

This ghost fish, of the family Aphyonidae, was filmed alive for the first time during a deep-sea dive. Observations like this are critical to understanding an organism’s life. We now have the first evidence of where these fish live!

How was the Mariana Trench formed?

The process by which the Mariana Trench was created is a geologically fascinating one known as subduction. On the Earth’s surface, there are thin plates that cover the planet’s mantle, which is made of molten rock. If two of these plates collide, one pushes down into the Earth’s mantle while the other is pushed over the bottom plate. When this happens, a trench is formed from the drag of the bottom plate. This process can sometimes create incredibly strong earthquakes. The plates that forged the Mariana Trench’s creation are estimated to be up to approximately 180 million years old.

This trench was unknown to scientists until 1875. It was then that a team of explorers on the HMS Challenger measured the depth of the sea by simply lowering a weighted rope into the water. They were baffled when they measured that first portion of the seafloor to be five miles below the surface. And so was born the origin of some of the most daring deep-sea explorations known to mankind to date.

Is the Mariana Trench protected?

The Mariana Trench is in waters off Guam and the Mariana Islands. The region is protected from some human activities under its status as a marine monument. The creation of the Mariana Trench Marine National Monument signified that international, national and local leaders all recognize the importance of protecting this area.

However, just because the region is protected does not mean it’s not vulnerable to modern threats to ocean health. Plastic bags have been spotted in the Mariana Trench during several expeditions, highlighting the far-reaching impact of the marine debris problem. No corner of our ocean is safe from the ever-present threat of plastic pollution. The reality of a changing climate makes the future well-being of wondrous places like the Mariana Trench uncertain. What’s more: More than 70% of the global ocean has yet to be mapped. And what we don’t yet know about, we cannot wisely work to protect.

It’s up to us to work together to defend our ocean, from the sandy shores of our favorite beaches to the deepest, darkest parts of the sea. Together, we can work to protect our ocean as a whole, which ultimately helps protect treasured places like Challenger Deep.

Find out how you can join Ocean Conservancy’s wave of momentum to secure a healthy ocean and a thriving planet, forever and for everyone!

The post The Mysteries of the Mariana Trench appeared first on Ocean Conservancy.

The Mysteries of the Mariana Trench

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Ocean Acidification

Soundscapes in the pearl of the orient seas: The Philippines!

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Intro

At the western tip of Luzon, which is the biggest island of the Philippines, lies the small coastal town of Bolinao. Tourists seldom find their way here as it takes around seven hours to get here by bus from Manila. Still, you can spot foreigners walking around every now and then, but they really stand out among the Filipinos. A reason for their presence is often that they study or work at the Bolinao Marine Laboratory (BML), which belongs to the University of the Philippines (UP). It is one of the seven research institutions participating in the GAME project 2026. Every year, GAME brings together Master’s students from all over the world to experience different cultures and conduct globally replicated experiments in marine ecology.

Konstantin buying veggies at the local market.

This year’s Team Philippines consists of Jona, a Filipino master student of Marine Biology at the University of the Philippines, and Konstantin, a German student who is enrolled in the Master programme „Ecology and Evolution“ at Freiburg University. As part of GAME 2026, we are currently staying at BML for 6 months to run experiments about the influence of underwater soundscapes on the colonization of marine hardbottoms.

Jona and Konstantin near the experimental sites.

Where are we?

At the BML, we live in a dormitory together with many other students and scientists mostly from the Philippines and a few international interns. At almost any time of the day there is someone in the kitchen to hang out with, eat together, or simply have a chat. It is easy to make friends in this little community. The way to work is just a short walk along a forest path, where we can pick mangos for a snack and spot butterflies, birds, or even wild macaques climbing through the trees. After crossing a street, we reach the institute. But instead of enjoying the cool temperatures of the laboratories, we spend most of our working days outside, doing fieldwork in or near the water.

The way from the dormitory to the institute.
The kitchen of the dormitory is always crowded with people cooking and laughing together.

On Fridays, Konstantin experiences real Filipino culture during an almost weekly party at the institute with karaoke and lots of food and drinks. And Jona even brought some German culture to the Philippines by baking German bread for everyone.

On Friday evenings the workplace changes to a party place with karaoke and Filipino food.

What do we do?

Even though Bolinao is a remote place, it can get quite loud. Tricycles and jeepneys pass by, children play basketball in the streets, and karaoke can be heard almost everywhere and at any time. But just a few meters offshore, the soundscape changes. Beneath the surface of the ocean, you enter a world filled with sounds that are not so familiar to humans. When you dive down, alongside the rhythm of your own breathing, you might hear the crackling snaps of shrimp, the grunts of fish, or the rumble of waves rolling overhead. Together, these sounds form a natural underwater symphony which, however, can easily be interrupted by the noise of passing boats.

The ocean in front of the institute is often full of boats.

Marine organisms use sounds to communicate and to gather information about their environment, and there is growing evidence that this also applies to the larvae of sessile invertebrates such as mussels, barnacles and tunicates. During their pelagic life they are presumably able to use sounds for finding their way to suitable habitats, in which the sessile adult life stage can survive and reproduce. But what happens when these natural soundscapes are disturbed by anthropogenic noise? And what is the effect when the soundscape in a degraded reef gets enriched with sounds of a healthy coral reef?

In our experiments, which we just finished a few days ago, we investigated how different underwater soundscapes influence the colonization of hard substrata by the larvae of marine invertebrates. For this, we placed PVC settlement panels in the water and exposed them to playbacks of either boat noise, or amplified recordings from healthy coral reefs. A further group of panels was not exposed to any playbacks. By comparing the communities that establish under these different acoustic conditions, we can determine whether soundscapes affect the settlement of larvae.

Challenges

In contrast to the other GAME teams of this year’s project, we don’t have a jetty at BML. So, our first challenge was to build a setup that could carry an MP3 player for the soundscape playbacks, an amplifier, and an underwater speaker, which all need electricity supply, and position it about 30 to 50 meters away from the beach.

We ended up building a floating frame that carries the settlement panels as well as the underwater speaker, and combined it with a waterproof box, which was above the waterline and contained all the sensitive technical equipment. The box was firmly sealed so that it withstood waves and heavy monsoon rains, while its interior remained dry. At the same time, it was protecte