Ocean of Hope

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 a pink manta ray

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 a pink manta ray?

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 a genetic mutation.

My pink pigments

So now you humans guess that it’s a “unique expression of melanin” or that my skin pigments 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’m a boy!

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) chase a female to try and mate with. Her pheromones are quite irresistible! If she’s looking for unique, I’ve got all the other boys beat–I’m a pink manta ray after all!

My biggest predator…

Even though as a pink manta ray 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!

Devil rays

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 because of that.

What are gill rakers?

Now us manta rays are 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 are what keep me alive!

Even pink manta rays can’t outsmart humans though…

Unfortunately, a new not-so-traditional and 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 cannot 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.

Also see Moby the Manta Ray: Happy Manta Ray Day!

For more on how you can help manta rays, visit these ocean 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

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?”

What Is Bioluminescence and Why Do So Many Deep-Sea Animals Have It?

bioluminescence, bioluminescent ocean waves, bioluminescent waves, bioluminescent plankton
Bioluminescent ocean waves Photo credit: Phil Gibbs on Visualhunt.com / CC BY-NC-ND

What is bioluminescence?


Bio = biological, or life, Lumen = light (unit)
Bioluminescence is the biochemical emission of light by living organisms such as deep-sea fishes. It produces the “glow-in-the-dark” look of certain animals such as fireflies and the “fireworks” show when plankton are disturbed in the ocean(see photo of bioluminescent ocean waves).

What percentage of animals in the deep-sea are bioluminescent?


90% of animals in the deep-sea (below 1,640 feet or 500 meters) are bioluminescent (according to NOAA [National Oceanic and Atmospheric Administration]).

How do animals and plants produce bioluminescence?


Two chemicals are mixed together with oxygen and the reaction produces light. The chemicals are luciferin and luciferase and together they produce oxyluciferan.

Bioluminescence is made up of what colors?


Mainly blue-green as red is absorbed the further you go down in the ocean. There are species that emit infrared and red light and one group of organisms that produce yellow light.
from Causes of Color website

What kinds of ocean animals are bioluminescent?


Bioluminescent ocean organisms include bacteria, jellyfish, starfish, clams, worms, crustaceans, squid, fish, sharks and more to be discovered! (list according to NOAA)

Why are animals bioluminescent?


Animals are bioluminescent for protection as the light will scare some predators away. The vampire squid has bioluminescent mucus that they eject (like ink) towards predators. Animals can use bioluminescence to find mates (which is hard when in the dark, deep sea with no other light). They also can use it to find food (like Dory in Finding Nemo being drawn to the anglerfish lure. Fortunately Dory wasn’t eaten!). Also it can be used in communication, and for illumination.

What questions do you have about bioluminescence? Leave a comment below.

10 Fun Facts About Opah Fish, or Moonfish

Opah fish, Moonfish, opah fish facts, opah fun facts
Opah fish or Moonfish photo by: NOAA Fisheries

1. The opah, or moonfish, is a fully warm-blooded, deep-diving flat and round fish.

2. The opah has a silvery gray body, red fins and mouth, and white spots all over.

3. Opah average 100 pounds (but can weigh up to 200 pounds) and is the size of an automobile tire-about 3 feet in diameter-but oval shaped.

4. Scientists have discovered recently through DNA testing that there are 5 distinct species of opah.

5. Opah eat fish, krill and squid.

6. Opah dive to depths of 165-1300 feet (50-400 meters).

7. Opah swim using their pectoral (side) fins and swim quickly like tuna.

8. Predators of opah include humans and large sharks such as great white sharks and mako sharks.

9. Scientists have tagged opah and found that they migrate thousands of kilometers.

10. Opah are caught as by-catch—by accident—by the tuna and swordfish fisheries. Off the United States, 30,000 opah were caught by the Hawaiian longline fishery in 2015 and the fishery is worth 3.2 million US dollars.

Also see a similar looking fish, the Mola Mola or Ocean Sunfish: 10 Interesting Facts About the Mola Mola or Ocean Sunfish

Articles used:
Opah, the first warm blooded fish identified: 7 facts you should know about it

Sleuthing Leads to New Findings About Peculiar Ocean Fish

Opah on animalspot.net

Meet the Comical Opah, the Only Truly Warm-Blooded Fish

Plastic Bits are Food? An Anchovy’s Perspective…

anchovy, anchovies, anchovies and plastic
Anchovies:Photo credit: Erik Sorenson via Visual hunt / CC BY

Anchovies can smell plastic pieces in the ocean and mistake them for food.

Plastic bits or food-they all smell the same to me. Hi, I’m Annie, and I’m an anchovy. You may have seen my colleagues in a tin can (may they RIP), or in the ocean in a large shimmery school that’s hopefully not being eaten by large predators such as sharks and dolphins, eek!

You might also wonder how we can smell in the first place, as we live underwater. Chemicals travel through the water and into my nostrils, just like they do in the air for terrestrial animals. Sharks can smell blood from very far away or in low quantities. Salmon use their sense of smell to navigate back to their birthplace spawning ground upstream.

Back to the plastic bits-humans have found that over 50 kinds of fish mistakenly eat plastic, thinking that it’s food. That includes my friends and I. A neat study by humans using an anchovy school in an aquarium (Aquarium of the Bay in San Francisco, California) found that by measuring our schooling behavior (how tight we schooled and our body position relative to water flow) that we:

1. Use odors to locate food

2. Plastic pieces are confusing to us due to their similarity to food in appearance and smell

So what can you do to help? Avoid single use plastics (SUP) whenever possible and recycle if you do buy them! Less than 7 percent of plastic in the U.S. gets recycled. Thanks for recycling, every little bit helps! Fortunately I won’t be around in 2050 when there is more plastic in the ocean than fish…

I used information from these articles:
Bait and Switch: Anchovies Eat Plastic Because it Smells Like Prey

The Numbers on Plastics