A"Nemo"ne Fish - Nemo's Real Story

It always fascinates people when I tell them about the real life of "Nemo", because their perceptions have all only been based on the cartoon movie that kids and adults alike all love. No doubt the love for "Nemo" worldwide has skyrocketed due to the movie, but other than knowing that the "Nemo" is adorable, what do you really know about this type of marine creature?

So, what is the "real" life of the Nemo, you ask?

The False Clown Anemonefish

Before we go into the shocking facts, do you know why the name "Nemo" is an appropriate name for the cute main character in the Finding Nemo movie?  That's because the main character Nemo is a type of anemonefish (note the underlined alphabets) in the ocean that lives within the tentacles of the Sea Anemone, an animal that looks like an upside down jellyfish with its tentacles swaying in the water (yes, it is an animal and not a plant).

The actual common name of the orange and white striped "Nemo" fish in the marine world is the False Clown Anemonefish.  Wait, you may ask....why is it a "false" one?  That's because...the real scientifically-known Clown Anemonefish actually has dark borders around its body (see picture below):

The "real" Clown Anemonefish, with black borders on its body.

Right, now that we have gotten that happy part straightened out, I have 4 main shocking things to reveal...

1) First of all, the Clownfish is NOT the only type of anemonefish you will see underwater.  There are many others which live within the tentacles of the Sea Anemone, some of them include....

the Pink Anemonefish (above), which is pink and has a white dorsal stripe from between eyes to tail, 

the Tomato Anemonefish (above, female), which is black on sides with red snout,

the Spinecheek Anemonefish (female, above), and

the Orange Anemonefish (above), with a white dorsal stripe running often from the lip to tail,

and the Clarke Anemone (above), which is black with white stripes, among many other kinds of anemonefish to be found.  

So next time when you see these fishes living within the tentacles of the Sea Anemones, you will know they are also anemonefish and are in the same family as the "Nemo".

2) Secondly, ALL anemonefishes are born as Males.
Yes! Question is - if they are all males, then who's going to be the female and how do Anemonefish reproduce?

The answer is this - the anemonefish can change their gender to become female at an appropriate time! So...when is the appropriate time?  Before answering that, you have to understand this - when you see a group of anemonefish living within the tentacles of a Sea Anemone, know that the largest of them all is the ONLY female living within that particular Sea Anemone.  The rest are all male.  The largest male in the group is the only one that will mate with the female for reproduction.  The rest are just juvenile males that do not mate with the female anemonefish.  No polygamy...yay!  !

Above: guess which is the female anemonefish?

Now, when the only female in the Sea Anemone moves to another home or is eaten up by a predator, the largest male in the group grows rapidly (averagely up to 25% bigger) within a short time and changes its gender to female.  It will then mate with the largest male now in the group, which would also have grown larger for the purpose.  Isn't that just fascinating??  

But that also means that the group you see living within a Sea Anemone is NOT a family like how the cartoon Finding Nemo depicts...sorry kids to burst your fantasy!

Above: a larger female anemonefish with eggs laid and adhered on a substrate beside the Sea Anemone

3) Thirdly, the Sea Anemone doesn't allow just ANY fish to live with it.
In fact the Sea Anemone ejects stinging nematocysts when touched (that's why, you should never touch the Sea Anemone!). However, the anemonefish is not afraid because it has a special layer of mucus on its body that protects it from the nematocysts stings.  It is one of only a few types of fish that can live within, and is protected from its predators by, the tentacles of the Sea Anemone (some others include the rare Banggai Cardinalfish which can also be found living with Sea Anemones).

And the Sea Anemone is pretty happy to have the anemonefish too.  The anemonefish's excrements benefit the Sea Anemone by providing nutrients.  In addition, by virtue of their bright colors, the anemonefish sometimes lure small fishes which the Sea Anemone prey on (I told you the Sea Anemone is an animal!).  These, and other benefits provided by the anemonefish create a Mutualistic Symbiotic relationship, whereby both the Sea Anemone and the anemonefish benefit from the relationship.

Don't be deceived by the beautiful colors of this bulb-tentacle Sea Anemone - it stings!

4) Lastly, the caretaker of eggs is the Male anemonefish (and NOT the female)!

The eggs of the False Clownfish - you can see the eyes of the babies! 

The eggs of the anemonefish take about 6-10 days to hatch after they have been laid.  During this time, the male anemonefish will take care of them by aerating them and guarding them against predators very aggressively, even against fish much larger than it.  The female only takes responsibility occasionally.  This is another case of gender equality underwater...(see my previous article about the cuttlefish, which has a similar story)!

Above: Male False Clown Anemonefish aerating and fanning the eggs 

The more time invested by the male anemonefish in fanning its eggs, the more rapidly the eggs will hatch (which explains why the hatching time period ranges from 6 - 10 days), and the more successful the development of the eggs.

So now you have a much better understanding of that cute looking Nemo.  Hopefully you can also tell others about the fascinating stories of the anemonefish! :)


(All photos, except that of the "real" Clown Anemonefish, are courtesy of the author Kathleen Ng)