clownfish gender question

[roka64]

If you introduce them all at once, they COULD be ok, but I doubt it. The Maroon might attack the other two. Personally, I wouldn't do it in my tank.

[loyalrogue]

Unfortunately I can't find a scientific article that specifically addresses your question, but there are tons of marine biology articles that breakdown the lifecycle and gender pattern of anemonefish in general.
They all state the basic facts that all anemonefish start as male juveniles.
When two or more are together, the largest will become female and the second largest will become the dominant male.
If the female dies the dominant male turns female and one of the juvenile males becomes the dominant male.
In every case and article I have read, the actual gender changing switch occurs only when it's "triggered" by the social necessity.
If an anemonefish is kept alone there is nothing to trigger or necessitate the gender switch to female.
Another thing to consider is that anemonefish can change gender from male to female, but cannot change from female back to male.
Therefore it would be contrary to the species survival for a single anemonefish to make an irreversible gender change without it being necessary for procreation.

It's safe to say that:

A) If your Maroon Clownfish was tankbred and taken from a group of juveniles then it is still a juvenile male and will remain so until you introduce another Maroon Clownfish to begin a social hierarchy.

B) If your Maroon Clownfish was taken from the wild or was kept in a tank with other Maroon Clownfish past the point of sexual maturity then there is a chance that it has already made the gender switch to female.

I haven't found any articles or information that contradicts the above information or what everyone else has posted.
If your friend says that we are "telling you wrong" then ask him to produce a scientific article that backs up his theory otherwise he's just spreading his own misconceptions.

[loyalrogue]

Originally Posted by choupic

What would happen if you put 3 clowns in one tank (55 gal) two Percula Clown - and one Maroon Clown ?

If they are all tankraised juveniles and added together then there shouldn't be any problems.
If any of them are from the wild or already have a territory established or a host anemone then I wouldn't advise it in such a small tank.

Originally Posted by Drs. Foster and Smith

Tank raised clownfish are not nearly as aggressive. Because these clownfish are raised in a group setting without host anemones, they usually do not develop these territorial aggressive tendencies. They are less likely to be aggressive to tank mates or other species of clownfish. In fact, one of the advantages of many of the tank raised clownfish is that they can be housed with other clownfish of the same or even different species. If the clownfish are added to the aquarium at the same time when they are young, they will often live together peacefully for their entire lives.

Read the full article.

[Tentacles]

loyalrogue thats just what i wanted to hear, and completely agree

''In every case and article I have read, the actual gender changing switch occurs only when it's "triggered" by the social necessity.
If an anemonefish is kept alone there is nothing to trigger or necessitate the gender switch to female.
If your Maroon Clownfish was tankbred and taken from a group of juveniles then it is still a juvenile male and will remain so until you introduce another Maroon Clownfish to begin a social hierarchy.''

do you have the article that stated these things because that would be even more amazing

[angelscrx]

Here's what I found.

Release from:
Adapted by Katherine Redding & Kathleen M. Wong
California Academy of Sciences
What the movie "Finding Nemo" doesn't tell you about clownfish is that they're all transsexuals. In a study published in the journal Nature, evolutionary biologist Peter Buston and colleagues report that clownfish in Papua New Guinea reefs can change their sex at will for social reasons. Clownfish live in strict hierarchical communities. Each neighborhood is dominated by a top-ranking female breeder. Her male partner is next, followed by up to four progressively smaller, non-breeding fish. When the dominant female dies, her mate changes sex and becomes female. The top-ranking non-breeder becomes a sexually active male, and all the other fish shift up a rank. Clownfish also appear to regulate their size in order to remain part of the group. Each fish keeps its body mass 20 percent smaller than the fish directly above it in social rank, probably to avoid conflict. Fish who disrespectfully outgrow their rank are rejected by the clan.

And one more.

Size does matter to sex-changing clownfish
Danny Kingsley
ABC Science Online
Tuesday, 15 July 2003



Clownfish change their size to keep harmony in the group (Shane Paterson, Nature)

Size does matter, especially if you are an aspiring clownfish: a U.S. researcher has discovered that male clownfish grow bigger and change sex if the breeding female is absent.

Clownfish, or Amphiprion percula, live in tropical waters worldwide. In the Madang Lagoon of Papua New Guinea, groups live among sea anemones, which help protect them from predators. Each group consists of a breeding pair and up to four non-breeders.

In these groups, the status of an individual is determined by its size. The largest of the group is the breeding female, followed in size by the breeding male, with the remaining non-breeders getting smaller as their rank decreases.

But Dr Peter Buston of Cornell University in New York found that this can change if the group dynamic is altered. His study is reported the latest issue of the journal, Nature.

He removed the breeding female from one group to see what would happen. In the group, every fish grew and moved up a rank, with the male breeder - the second-largest - growing larger and then turning into a female. The largest of the non-breeders in turn grew, and then turned into the male breeder.

Buston suggests that the strategy may have evolved to prevent conflict between group members, because it ensures that subordinates do not become a threat to their dominants.

The group arrangement is advantageous to non-breeders, who have the chance of moving up the chain; but it is not so good for the breeding pair as the non-breeders can be a threat if they get too large. Breeders sometimes kill or evict non-breeders that have grown to a similar size as the breeders.

These results indicate that the growth rate and size adopted by animals that live in groups can be a strategic response to their social environment. By comparison, in other group situations, animals modify their behaviour within the group instead.

Hope that helps?

[Tentacles]

great articles, but it doesnt address the issue of a clown being by itslef in captivity or the wild, if a clown is alone in a tank, and has no contact with any other clown or fish of any kind, what sex will the clown become at maturity.

Weve established that it is male/unisex but there isnt an article yet that ive found to proove that.

loyalrogues answer i quoted above is what im looking for, but in an actual article. this guy is driving me crazy, he insists they become female after a month.

[Devilishturtles]

Okay, so here is what I did. Some of the most knowledgable people in the hobby run that wet web media website, so I sent 'em an email with our question, because now I really want to know the truth behind all this conflicting information.

Hi WWM Crew. I was hoping you could be of some assistance to a difference of opinion my friends and I are encountering. We are aware that clownfish are born gender-neutral/male and will establish the female gender based on heirarchy, dominance, size, and things of the like. Our question is, what happens to a clownfish that is raised alone, without another? Will it stay gender neutral, or will it change into a female as well? Does it vary on different situations? There seems to be many a different opinion on the web. Thank you for your time! It is much appreciated.
-Lindsay

Hopefully it will not take them too long to respond.

[Tentacles]

sweet, thanks much

on a lighter side i got a new 2 headed frogspawn a ricordea a three headed caulestra (if they are referred to as headed) and a little zoa colony today in the mail, only paid 40 bucks for it all on frags.org, awesome deal, the frogspawn and the ricordea look great already

[loyalrogue]

Originally Posted by Tentacles

great articles, but it doesnt address the issue of a clown being by itslef in captivity or the wild, if a clown is alone in a tank, and has no contact with any other clown or fish of any kind, what sex will the clown become at maturity.

Weve established that it is male/unisex but there isnt an article yet that ive found to proove that.

loyalrogues answer i quoted above is what im looking for, but in an actual article. this guy is driving me crazy, he insists they become female after a month.

My advice to you is to ignore him and don't let him drive you crazy with misinformation that he can't back up.
As I said, there isn't a scientific article that addresses your specific question because that isn't a situation that happens.
You will not find any article on the web or anywhere that states anemonefish become female after 1 month because it isn't true.

If they became female when alone don't you think that one of the thousands of marine research papers or sites would have mentioned it???

As a matter of fact, most anemonefish don't even reach sexual maturity until after they're over a year old... so your friend saying they turn female after a month doesn't make any sense at all.
At a month old they've barely turned from larva into juveniles.
You can't even buy them in a LFS at that age.
If what he said were true then every single lone Clownfish in every LFS would be female, and we all know that's not true.

I've really tried and I can't find one single article that backs up your friend's claims and says that anemonefish turn female if they're kept alone... whether it's after a month or after 5 years... so I really have no idea where your friend could be getting his information from.
Let's take a moment and look at some of the thousands of available articles on anemonefish and their lifecycles...

Originally Posted by MarineBio.com

All anemonefish are born male with active male and dormant female reproductive organs. If the female dies, then the dominant male will sex-change into a female, and a non-dominant male will change into a dominant male. This allows anemonefish inhabiting one anemone to remain self-sufficient in that if the female dies there is no need for the male to find a new mate. The responsibility for caring of the eggs becomes the "new" female's job!

Full Article
Nope, nothing about turning female when alone.

Originally Posted by Australian Government Site

As a general rule anemonefish enter into permanent monogamous pairings. Juveniles live on an anemone with a sexually mature male and female pair. If the female dies, her male partner develops into a female to take her place. The largest juvenile then grows rapidly and replaces him as the dominant male.

Full Article
Nope, nothing about turning female when alone.

Originally Posted by University of Michigan Museum of Zoology

One of the most interesting characteristics of anemonefishes is that all offspring are born male, and mature as such. Therefore, all females are sex-reversed. This sexual metamorphosis occurs when the female of a group leaves. This will trigger the largest male remaining to switch sexes and will allow the largest juvenile to become a mature male. The adult pair will then continue to stunt the growth of the remaining offspring.

Emphasis mine.
Full Article
Nope, nothing about turning female when alone.

Originally Posted by World Association of Zoos and Aquariums

Anemonefish are born male with active male and dormant female reproductive organs. If the female dies, then the dominant male will change sex into a female, and a non-dominant male will change into a dominant male.

Full Article
Nope, nothing about turning female when alone.

Originally Posted by Ichthyology at the Florida Museum of Natural History

The maturity age range for both male and female pink anemonefish is 1.75 to 1.83 years. When they reach maturity, reproduction takes place primarily between the months of April and August, but can occur in February. This species live in social groups that have a strict dominance hierarchy. The larger fish is always the female and the second largest is the male. They are the only two individuals that reproduce within the group. Pink anemonefish's mode of reproduction is protandry in which only the testicular tissue matures. Under certain conditions- the death of the female- testicular tissue degenerates and the gonads change to ovaries, thereby allowing the fish to avoid self fertilization.

Full Article
Emphasis mine
Nope, nothing about turning female when alone... as a matter of fact, this article goes so far as to explain the age of sexual maturity (almost 2 yrs old) and the degenerative tissue process that accompanies gender change. That is an extreme and irreversible biological process that the fish is not going to go thru until it joins a group and it becomes an absolute necessity for mating.

If your friend insists on giving you a hard time and won't listen to reason then tell him to sign up here and post whatever information he has.
The whole point of this place is to share good info, dispel bad info, and to help each other become better aquarists.
The fact that you're here asking questions and he's so stalwart in his ignorance just tells me that you are going to become a much more reliable authority on aquariums than your friend could ever hope to be.


Good luck.

[Devilishturtles]

Wow, nice post loyalrouge! Thanks for taking the time to round up all that info. I feel the same as you and everybody else here. If it really is one month, these are some poorly written articles because they don't mention it.

Now, we can just wait for one of the WWM people (perhaps Mr. Fenner himself will reply to my email!) and prove this other dude incorrect.