Happy World Manta Ray Day!

manta ray named Cherilyn
Manta Ray named Cherilyn (yes, after me!)

Happy World Manta Ray Day! This is Moby, and I’m a manta ray. I’ve been lucky to be featured in this blog, see Moby the Manta Ray: I Am Not a Devilfish Part 1, Moby the Manta Ray Part 2: How I Am Alike and Different From My Cousins the Sharks and Why Manta Rays Are Becoming Endangered and today I felt the need to bring up the state of the ocean I live in.

We manta rays really are gentle giants, reaching lengths of 23 feet (7 meters) and 6,600 pounds (3000 kg). But all we eat are plankton, the tiny plants and animals floating in the ocean. And we don’t have a stinger on our tail like stingrays. Our only defense is our size, but as you’ll find out, it’s no match for humans.

I face so many threats living in the ocean including pollution (especially plastic), ghost nets, and being fished out by fishermen, to name a few.

I’ve heard things are going poorly on land, but at least you’re not swimming around in and eating garbage! I mean that literally—junk food is nothing compared to the microplastic I ingest everyday.

Microplastic are small bits of plastic. Some pieces are grinded down from larger pieces, and some are manufactured that way (like microbeads in beauty products).

I eat plankton, the tiny plants and animals that live in the sea. The microplastic floats around with the plankton. I filter the seawater around me through my gills, and have finger-like gill rakers on my gills that trap the plankton, which I then swallow.

Each gulp of water brings probably thousands (or more!) microplastic bits in which I swallow. This plastic bioaccumulates in my body, which means that little by little the plastic builds up in my body over time.

You, as humans, carry several pounds of plastic in your body. Even human babies are born with plastic in their bodies.

It’s ironic, the very structure that keeps me alive—my gills—helps me to breathe oxygen from the water around me, and also helps me filter out the food I eat— may lead to my downfall.

You see, me and my manta ray friends’ gill rakers are used in a new controversial Traditional Chinese Medicine formula created in modern times. Some TCM formulas date back 2,200 years but not this one. This means now that manta rays are being hunted exclusively for our gill rakers.


We weren’t always well-liked by fishermen in the past because we manta rays would get caught in their nets and ruin them. They nicknamed us “devil rays” because of that and because our curled up head fins look like devil horns.

Phew, don’t get me started on the dangers of fishing nets to manta rays. If we do get caught in a fisherman’s net there’s no guarantee that we’ll get set free in time to survive.


And there’s something called ghost nets which also lead to many manta rays and other large sea creatures dying. Ghost nets are fishing nets that fishermen have abandoned at sea. Many times they are made of a semi-transparent material called monofilament which looks nearly invisible underwater to most sea creatures.

Once tangled in one, it’s likely that the animal, like a sea turtle, shark or dolphin will die without getting enough oxygen. Sea turtles and dolphins need to get oxygen from air and sharks need to swim constantly to move water over their gills to breathe.

How can you help? You can visit the websites below and donate your time or money. Or just learn more about me and my manta ray friends and spread the word about our plight.

Please vote and let legislators know the health of our oceans matter to you (and me especially!).

Manta Trust
Dr Andrea Marshall, the Queen of the Mantas
Manta Pacific Research Foundation
Marine Mega Fauna Foundation
Wild Aid Manta Ray Program

Meet the Pink Manta Ray!

pink manta ray, manta ray Australia
Pink Manta Ray from Australia photo by Kristian Lane/Instagram

Yes, I’m really pink. My belly is pink, whereas in “normal” manta rays their belly is white with black spots and splotches on it. I’ve been nicknamed “Inspector Clouseau” from the movies and tv program called the Pink Panther. You clever humans!

Why am I pink? I don’t know, I think I was just born that way. You intelligent humans have ruled out stress. From a small skin sample (a biopsy) they have ruled out a diet full of red food, it’s not an infection or genetic mutation.

So now you humans guess that it’s a “unique expression of melanin” or my pigments in my skin are just “off”. Duh, I could’ve told you that! After all there are “strawberry blonde leopards,” and “fuchsia grasshoppers,” due to something called erythrism. That causes animals to appear reddish or pinkish.

I was first seen in 2015 off of Australia’s Lady Elliot Island. I’m now 11 feet wide (wingtip to wingtip) and yes, I’m a boy. I was last seen as part of a courting train, which is when a line of males (in this case 8) chases a female to try and mate with her. Her pheromones are quite irresistible! If she’s looking for unique, I’ve got all the other boys beat!

Even though I stand out in a crowd of manta rays, I’m relatively safe from killer whales and great white sharks due to my size. In fact, my biggest potential predator is you humans!

Yes, all manta rays are at risk at being targeted and hunted by humans. Fishermen nicknamed us devil rays because our curled up head fins look like devil horns. We would often get tangled in their fishing nets and ruin them. They really didn’t like that or us.

Now us manta rays are being targeted for our gill rakers. They are thin, comb-like strings on our gills that capture all the yummy plankton from the water I strain through my gills. In other words, my gill rakers keep me alive!

Unfortunately, a new not-so-traditional controversial formula of Traditional Chinese Medicine utilizes gill rakers and humans now target us gentle and giant beings. We manta rays have the largest brain-to-body ratio of any fish, but alas, even our intelligence can keep us from being hunted, possibly someday to the point of extinction. Coupled with our lack of defense (we have no stingers) we have little hope of surviving unless humans stop targeting and killing us faster than we can reproduce. Its no wonder females have a train of males trying to court them—they only mate every two years and have pups every 2-5 years.

For more on how you can help manta rays, visit these conservation non-profits:

Manta Pacific Research Foundation

Manta Trust

Marine Megafauna Foundation

Wild Aid’s Manta Ray Program

Articles used in this blog post:

Rare pink manta ray spotted near Australia’s Lady Elliot Island

How manta rays gill rakers filter water without clogging

Manta ray reproduction

Manta Rays Have Social Lives!

manta ray, reef manta ray, Manta alfredi
Reef manta ray (manta alfredi) photo by: Shiyam ElkCloner, Wikimedia Commons

Hee, hee. Did you know manta rays have a social life? I know because I AM a manta ray. My name is Molly. Humans have only studied manta rays in depth (probably) for decades. Before we were admired for being a gentle giant, fishermen called us “devilfish.” Our curled up head fins look like devil horns, hence the name. Never mind most of the time we’re feeding and our cephalic fins are uncurled. We’d often get caught in fishermen’s nets by accident. The fishermen would get angry that not only did they have to untangle us, but they often had to repair their nets.

In any case, humans have come out with a research study showing that female reef manta rays (Manta alfredi) “show preference” to other female manta rays. I’d say we’re friends, or acquaintances at least for the short-term. We also remember our contact with each other.

We form bonds with other female manta rays over weeks and months but not necessarily longer. That’s okay as many times after a feeding frenzy, or a stop at a cleaning station, we go our separate ways. We don’t vocalize like whales, who keep in touch at long distances. When we get excited socially we can brighten the white splotches on our black backs. But we do have the largest brain-to-body ratio of any fish so it’s no wonder we can use some of our brainpower to recognize others.

The boys, well they’re on their own unless they group with other males, females and juveniles. The main times we all come together are for feeding (plankton for all!), at cleaning stations (ahh…), and for mating. A train of males will trail a female for a long time until she gives in and mates with one. It’s fun, up to a certain point. Who doesn’t like all that attention?

We are in trouble nowadays because of our gill rakers. The very body parts that keep us alive are now threatening our lives. Gill rakers are a covering on my gills, which not only help me breathe, but also feed. The gill rakers act like strainers. They filter ocean water as I swim. Plankton in the water stick to the gill rakers. Plankton are the tiny plants and animals that live in the ocean and are at the bottom of the food chain. The plankton builds up on my gill rakers and yum, time to swallow!

Unfortunately many humans covet our gill rakers for the Traditional Chinese Medicine market. There is no traditional formula that contains manta ray gill rakers, just a controversial new one.

I only have 1-2 pups every 2-5 years. That’s not very often, and we certainly can’t keep up with the fishermen killing us.

Other threats to manta rays, which are making us become endangered, are injuries from being entangled in discarded fishing nets, pollution (especially microplastics) and habitat destruction.

For more information on how you can help visit:

Marine Megafauna Foundation’s work with manta rays

Manta Trust and threats to manta rays

Wild Aid’s work in China to save manta rays

Paper published on 22 August 2019: Rob Perryman et al, “Social preferences and network structure in a population of reef manta rays” Behavioral Ecology and Sociobiology

Ocean Animals and the Mirror Self Recognition Test

dolphin mirror test, mirror self recognition test, self aware animals
Dolphin reacts to own image in mirror

With recent news that the cleaner wrasse might have mirror self-recognition (MSR), I thought I’d write about the ocean animals that have MSR. Bottlenose dolphins and killer whales have MSR for certain. Possible mirror self-recognition ocean animals include manta rays and cleaner wrasses. Ocean animal that failed the mirror self-recognition test is the octopus.

So what is self-recognition? With a mirror, self-aware animals such as chimpanzees and bottlenose dolphins recognize themselves and don’t react as if the image is another animal of the same species. Some animals that don’t have self-recognition react to their image in a mirror with aggression or other more positive social behaviors.

The mirror self-recognition test is when a human researcher places a mark somewhere conspicuous on a captive animal. With human babies, they place a paint mark on their foreheads. Starting at 18 months, human babies investigate the mark when they see themselves in a mirror.

Then the researchers place the test animal in front of a mirror and judge from their actions (usually curiosity) if they recognize themselves or not. Here are some examples from the ocean:

Bottlenose dolphins in captivity react to a mirror image by “opening their mouths, sticking out their tongues and showing novel behaviors.” When marked, they investigate the mark on their bodies by moving the marked area towards the mirror.

Killer whales in captivity were shown themselves unmarked in a mirror. Then they were marked. The whales behaved like they expected their appearance to be altered. This showed that they have self-recognition.

Manta rays possibly show mirror self-recognition. When captive manta rays had a mirror placed in their tank, they blew bubbles, which they normally don’t do. They also appeared to investigate their image in the mirror by turning their belly towards the mirror and swimming by the mirror repeatedly.

Cleaner wrasses were injected with a mark, which is how scientists mark fish in their studies. When their throats were marked and a mirror placed in their tank, the cleaner wrasses would rub their throats against the tank. Throat rubbing is not behavior seen in wild cleaner wrasses. When the mirror wasn’t in the tank, the wrasses didn’t rub. So seeing the mark in the mirror caused the throat rubbing and hence cleaner wrasses possibly have self-recognition.

As a side note, the inventor of the mirror self-recognition test, Gordon Gallup of the State University of New York, doesn’t think cleaner wrasses have self-recognition and that the study was flawed. What do you think?

Octopuses haven’t passed the mirror test, but in studies they do orient themselves towards the mirror. Octopuses rely on their sense of touch and don’t rely on vision as much as mammals do, so it makes sense they don’t show mirror self-recognition.

On a personal note, I have dived with manta rays off the coast of Hawaii. I looked them in the eye and saw straight into their soul. It was no different than looking into a dog or cat’s eyes. I knew something was going on behind them. I don’t doubt that manta rays are thinking beings and that they may be self-aware.

Websites consulted:
List of Animals That Have Passed the Mirror Test
Article, “Is this Fish Self-Aware?”

My Manta Ray Encounter

manta ray
Close encounter with a manta ray (notice the plankton in the water) photo by: Cherilyn Jose

This blog post won second place in the 2016 San Mateo County Fair’s Literary Contest for best blog entry!

My Manta Ray Encounter

From the back of the boat, I made a giant stride into the black nighttime water. Underwater, the cumbersome SCUBA equipment strapped to my back was weightless. Warm water crept into my wetsuit. Exhaling, I descended into the pitch black. Pinching my nose and blowing out through it cleared my ears every few feet, and the pain in my ears felt like when ascending in an airplane. Exhaled bubbles surrounded and reassured me. My only lifeline underwater was working properly. I paused to marvel at breathing underwater.

My descent stopped near the bottom of the coral reef. Narrow beams of light danced around as other divers searched for life on the night coral reef. My highlighted view showed motionless fish sleeping. Multi-legged critters scampered out of my light. A hungry moray eel caught an unwary squirrelfish.

Ten minutes of swimming brought me to the “campfire.” Placed in the center of this underwater campfire was a bundle of dive lights so the insects of the sea, tiny plankton, swarmed together. Swarms of plankton attracted various hungry sea animals including fish, and the guests for the night. Divers pointed their lights towards the surface to attract more plankton. Settling down on my knees in the moderate current, plankton surrounded me. Little white dots darted to and fro in front of my dive mask. My dry mouth came from breathing the arid air from my tank and made me cough into my regulator. My eyes watered from the coughing, then cleared. Something emerged in the distance.

From the muted black darkness, and through the backdrop of the bright Hollywood lights of videographers, came an alien behemoth that glided over the all the divers. She was the star attraction for tonight, a manta ray. Her black back with white patches looked spray painted. Her flattened head and head fins swayed in her swim path. Her head fins unfurled to help funnel water into her cavernous mouth.

Her diamond-shaped body measured at least 6 feet across. She flapped her triangular pectoral fins in unison like a bird’s wings. Each powerful flap of her wings sent her flying within inches of divers’ heads.

The manta ray’s black back contrasted with her stark white underbelly. Her belly was full of black splotches. Splotch patterns are as unique as a human fingerprint and they allow scientists to identify and name individuals over time. The manta ray I saw was named Shirley. She gracefully flew inches over my head. I was reminded of the opening scene from the original Star Wars movie when an Imperial Star Destroyer appears to fly over the audience’s heads.

We divers are not supposed to hold their breath underwater, but in a briefing on the boat we were told not exhale bubbles directly onto a manta ray. I unconsciously held my breath as having Shirley so close to me took my breath away. I looked straight into one of Shirley’s eyes. They reflected such depth and soul that I couldn’t help but feel a deep connection with this alien being. It was like looking into a mammal’s eyes. Only manta rays are fish. They have the largest brain of any fish in the ocean, and a similar brain to body ratio as mammals. There is no doubt in my mind that manta rays are thinking beings. What they are thinking is a mystery to us humans though.

With her mouth agape, Shirley’s wide throat was visible. Her gills reverberated from the passage of water through them. A manta ray’s gills not only extract oxygen from the water around them, but also extract food like plankton. She closed her mouth periodically, presumably to swallow the plethora of plankton caught in her gill rakers.

I watched in awe as Shirley did loop de loops to gather plankton. The barrel rolls that manta rays perform are a magnificent underwater ballet. They are elegant and graceful. I could watch them for hours barrel rolling.

Later, another manta ray showed up. His name was Uhane Nui, which means “Great Spirit” in Hawaiian. Estimates placed his wingspan at eight feet across. Manta rays are the largest rays in the ocean. This one was huge. Shirley stayed in the lights, but Uhane Nui faded into the darkness and emerged from the bright videographer lights. Each appearance was a surprise and delight. The manta rays could come within inches of the divers and never bump into them. They could turn on a dime.

That magical night off of Kailua-Kona, Hawaii was my first encounter with manta rays. Upon arriving home, I devoured all the information I could find about them. I was dismayed to find out manta rays are killed when they get stuck in fishermen’s nets. Historically, fishermen would exact revenge on any manta rays that got stuck in their fishing nets and kill them.

I was later horrified to learn that today manta rays are now being targeted by fishermen. I got involved in the fight for California to ban the sale, trade and possession of shark fins. Now, much like sharks being targeted only for their fins, manta rays are now being hunted solely for their gill rakers. Gill rakers are used in controversial new formulas of Traditional Chinese Medicine. Often those hunting for shark fins will fin a shark alive and toss it back into the ocean to die a slow and agonizing death. Similarly, those hunting manta rays will kill them, cut out the gill rakers, and throw out the rest of the manta ray. Killing them that way is inhumane and wasteful.

A live manta ray is worth more alive than dead. Experts estimate a manta ray is worth one million USD over its lifetime due to ecotourism, but worth only five hundred USD when dead. Globally manta ray tourism is estimated to be 100 million USD annually. I’m hooked on SCUBA diving with manta rays-I will add to that total!