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baldomero
12/30/2008, 02:35 PM
hey guys i have 4 nems in my tank that were caught not too far off shore here in puerto rico by the guy i buy fish and inverts from.now my question is as u all know in the caribbean there are no clown fish so nothing hosts anenomes over here if i buy a clown would he host my nems and would the nems let the clown host them what do u guys think

Brandon M
12/30/2008, 02:37 PM
I don't know for sure about the anemone accepting the clowns, but I do know every clown is different. Some have had clowns that won't host for 1-2 years, and others that will go right for it. Every fish is different.

Good luck!

jenglish
12/30/2008, 02:39 PM
<a href=showthread.php?s=&postid=14043518#post14043518 target=_blank>Originally posted</a> by Brandon M
I don't know for sure about the anemone accepting the clowns, but I do know every clown is different. Some have had clowns that won't host for 1-2 years, and others that will go right for it. Every fish is different.

Good luck!
+1, its always a crap shoot.

Brandon M
12/30/2008, 02:39 PM
Also, you may have more luck posting in the Anemone and Clownfish (http://www.reefcentral.com/forums/forumdisplay.php?s=&forumid=36) section.

reefworm
12/30/2008, 02:41 PM
Brandon is right that every clown is different. That said, most anything with tentacles will host a clown [notice the grammar shift ;)] Mine was hosted for years in a
Euphylia ancora - hammer/anchor coral. Others have reported hosting by other Euphylia sp., sarcophyton and other leathers, bubbles, short and long tentacle plates, you name it

surge19us
12/30/2008, 03:43 PM
Mine are tank raised and chose to ignore my Frogspawn and Torch and instead are playing with fire.

http://i461.photobucket.com/albums/qq339/surge19us/CIMG0688.jpg

noboddi
12/30/2008, 03:53 PM
Every clown is different, but if the anenomes were collected near Puerto Rico then they are not natural hosts. There are only 10 species of host anenomes, and all the anenomes and clowns live in the Pacific.

Many of the clowns in stores today are tank raised, and have never seen an anenome in their life. Even when you have the correct clown species and the correct host species, the clown may not choose to bond. It all comes down to the individual fish.

Toddrtrex
12/30/2008, 04:25 PM
<a href=showthread.php?s=&postid=14044069#post14044069 target=_blank>Originally posted</a> by noboddi
............

Many of the clowns in stores today are tank raised, and have never seen an anenome in their life. Even when you have the correct clown species and the correct host species, the clown may not choose to bond. It all comes down to the individual fish.

Tank raised or wild caught isn't an issue. Being hosted is an inborn instinct as opposed to a learned one.

reefworm
12/30/2008, 04:29 PM
surge - never seen that one before! Has the clam tried closing on it, or do you know of incidents in which a clam has killed a fish like that?

eyesinthedrk
12/30/2008, 04:35 PM
i have seen pics of a clown INSIDE the clam its not uncommon

surge19us
12/30/2008, 05:16 PM
The clam sometimes partially closes and the clown leaves. At night the clam closes and the clowns sleep next to it.

noboddi
12/30/2008, 06:14 PM
<a href=showthread.php?s=&postid=14044282#post14044282 target=_blank>Originally posted</a> by Toddrtrex
Tank raised or wild caught isn't an issue. Being hosted is an inborn instinct as opposed to a learned one.

We're getting off topic here, but it depends upon clown species. Some clown species are pre-disposed to their anenome host species by the mucus off the anenome that their parents laid the eggs next to. Having this absent in their developmental period has an effect. In my experience, tank raised are less likely to host. Whether it is for this, or for some other reason, because quite frankly the interactions between 29 species of clowns and 10 species of hosts is not well understood, it's hard to say.

But tank raised are not the same as wild.

I have also seen many common clowns (Amphiprion occelaris) host in a BTA (Entacmaea quadricolor) which is not a natural host, so in an artificial environment you get interactions not found in nature, which goes to it's more than just instinct. I had one host in a Sinularia with a perfectly good BTA in the tank.

greenbean36191
12/30/2008, 06:17 PM
Tank raised or wild caught isn't an issue. Being hosted is an inborn instinct as opposed to a learned one.
Searching out a host is an instinct, but which host to search for isn't entirely. Imprinting plays a big role, so wild caught or tank raised does make a difference. You're less likely to get a wild caught clown to take an unnatural host.

abraha
12/30/2008, 07:14 PM
My clowns host a big mushroom. It's hard to say if your clown will host your nems or not. Only time will tell.

reefworm
12/30/2008, 07:33 PM
If I invite them in, them I'm the host. There, I've said it. ;)

baldomero
12/30/2008, 08:38 PM
maybe i will buy a clarkii clown and see if the nems would host em but couldnt the nems grab the clown and eat em or do clowns have a resistencee to their stickiness

noboddi
12/30/2008, 08:44 PM
<a href=showthread.php?s=&postid=14045008#post14045008 target=_blank>Originally posted</a> by greenbean36191
Searching out a host is an instinct, but which host to search for isn't entirely. Imprinting plays a big role, so wild caught or tank raised does make a difference. You're less likely to get a wild caught clown to take an unnatural host.

Again, depends on the species. Species like A. occelaris seem to imprint. A. clarkii does not seem to imprint, and it is probably no coincidence that this is the only species that uses all of the host anenome species. And some species have been observed in the wild with no host at all. They are not obligate symbiants.

It is not as simple as it is often portrayed. Which is why the "it's a crapshoot" advice is accurate.

noboddi
12/30/2008, 09:20 PM
I should add that while clarkii's are the easiest to get to accept a host, they are one of the larger clown species, one of the more territorial and also one of the more aggressive species.

greenbean36191
12/31/2008, 07:35 AM
Again, depends on the species. Species like A. occelaris seem to imprint. A. clarkii does not seem to imprint, and it is probably no coincidence that this is the only species that uses all of the host anenome species. And some species have been observed in the wild with no host at all. They are not obligate symbiants.
References? This is part of what I work on and your claims are completely counter to my experience and all of the published literature I'm aware of.

paraletho
01/01/2009, 04:44 PM
So Greenbean your saying it is similar to a salmon smelling for his birth stream or a sea turtle the sand that that they were hatched in. Not completely but in some part.

noboddi
01/01/2009, 06:55 PM
<a href=showthread.php?s=&postid=14048432#post14048432 target=_blank>Originally posted</a> by greenbean36191
References? This is part of what I work on and your claims are completely counter to my experience and all of the published literature I'm aware of.

There was an article in French journal a few years ago, Do the anemonefish Amphiprion ocellaris (Pisces: Pomacentridae) imprint themselves to their host sea anemone Heteractis magnifica (Anthozoa: Actinidae) ?, by Arvedlund and Nielsen who experimented with A. occelaris fry. The conclusion is that they found the host by smell, did not imprint, and suggested a genetic pre-disposition to H. magnifica.

Check out some Australian Museum site. They discuss that there are 28 (we now know there are 29 with A. barberi) species and each species has an individual relationship with it's host, so what is observed for one species may (or may not) apply to another species.

Allen and Fautin have observed two methods of anenomefish becoming immune to the host. One being that some species of anenomefish have a mucus covering rendering themselves invisible to the anenome, the other being that the anenomefish coats itself in the mucus from the anenome and acclimates over time. Occs and Percs do the first, Clarkii does the latter, I have not seen any articles where this has been studied for all the anenomefish and anenome host combinations.

Bob Fenner has written hat he has observed anenomefish living on the reef without a host. That brings into question the whole theory of obligate symbiosis, and that makes sense as they adapt so well without a host in an aquarium (can you imagine a coral living without zooxanthella?)

IME, the hobby literature over generalizes. An observation made on Occs and Percs, the most common bred species, is carried over to all clownfish. Not always accurate.

greenbean36191
01/01/2009, 10:37 PM
I'm good friends with Mike and very familiar with his work. You should reread it. They do locate the host by smell, but they recognize the smell due to imprinting. Naive fish show no directed swimming in response to olfactory cues. Their does seem to be some innate recognition when the fish can see the host, but the response is much weaker than imprinted fish. He's published similar work on A. melanopus that shows that they imprint as well. He's also done unpublished work with several other species and all species he tested (including A. clarkii) showed some degree of imprinting except maroon clowns, which only have one host species. Aside from those he's directly tested, he's investigated egg placement preference among about 4 or 5 other species and their choices suggest they choose nest sites that maximize the amount of chemical cues washing over the eggs, despite the danger to the larvae at hatching.

Aside from A. sebae and P. biaculeatus all of the other anemonefish common in the hobby have multiple host species so are more likely to imprint than not.

Allen and Fautin have observed two methods of anenomefish becoming immune to the host. One being that some species of anenomefish have a mucus covering rendering themselves invisible to the anenome, the other being that the anenomefish coats itself in the mucus from the anenome and acclimates over time. Occs and Percs do the first, Clarkii does the latter, I have not seen any articles where this has been studied for all the anenomefish and anenome host combinations.
These are the two leading hypotheses. There is evidence from various studies that supports both, but I don't know of any studies showing definitively that ANY species uses one or the other or that different species do it differently.

Elliot and Mariscal tested combinations of 10 clown species with 9 anemones and their work suggested it's the fish's own mucus in all cases. Still, the issue was far from settled the last time I really gave it any attention (probably 4 years ago).

Bob Fenner has written hat he has observed anenomefish living on the reef without a host. That brings into question the whole theory of obligate symbiosis, and that makes sense as they adapt so well without a host in an aquarium (can you imagine a coral living without zooxanthella?)
I think the simple explanation here is that Fenner's observations were erroneous. There are no such observations in the peer reviewed literature and it's unlikely that so many authorities like Fautin, Mariscal, Allen, Chadwick, etc. would repeatedly say that clowns are indeed obligate if they could be found without anemones.

It's certainly not at all hard for me to imagine how Fenner could be fooled though. When I work in the field we have to mark all of the anemones in the study site. The easiest way to locate the anemones is to look for the fish. Fairly often though we come across fish where we can't find any sign of an anemone no matter how hard we look. When we see that we put a tag down anyway because we know there is an anemone hidden there somewhere. We have yet to be disappointed. Sometimes it takes a couple of dives to find it, but an anemone always eventually reveals itself. Unless you're doing repeated dives looking for the same animals though, you might conclude there's no anemone there.

Aside from the lack of corroborating evidence for Fenner's observations in the lit, there is good evidence that clowns really are obligate symbionts. When you experimentally remove anemones in the field the fish either relocate to different anemones or are eaten, often within minutes. In areas where aquarium collection occurs there is also evidence that the clownfish population is controlled by collecting pressure on the anemones. Similarly, preliminary work I was involved in has shown that the number of adult A. bicinctus is controlled by the availability of E. quadricolor.

I think the fact that they do well in captivity without hosts can simply be attributed to the lack of predators.

noboddi
01/01/2009, 11:10 PM
I would read the study on imprinting. They tested many scenarios, and one was hatching fry with a different species of anenome (do not recall which one). The fry in that scenario reacted to H. magnifica in about the same percentage as the fry in the other scenarios. The preferred H. magnifica when presented with both species. Their conclusion is that imprinting did not play a significant role and the hypothesis is a genetic component for occs

greenbean36191
01/02/2009, 12:03 PM
As I've said before, I'm very familiar with Mike's work and have discussed it at length with him first-hand. You're combining the findings of two different studies and not getting the details of either right.

In the first study he raised A. ocellaris with and without a natural host anemone (H. magnifica) present. Imprinted fish showed strong directed swimming to the source of the host smell even when it was hidden. Naive fish showed no directed swimming. That indicates that imprinting was responsible for the olfactory recognition of the host. When fish were allowed to see the host, naive fish took days to approach and enter the anemone whereas imprinted fish found it and entered within minutes. The fact that both eventually found and entered the host suggests that there is some innate recognition, but the difference in response to the chemical cues and time to enter the host shows that imprinting is likely the major factor in host recognition. From the paper:
"The results of this study suggest that Amphiprion ocellaris imprints itself olfactorily to its species-specific host sea anemone Heteractis magnifica, and, furthermore, may be genetically disposed towards olfactory recognition of the host sea anemone."

The other study he published was with A. melanopus. In this one he hatched the eggs without a host, with a natural host (E. quadricolor), and the unnatural host H. malu. Those raised without an anemone were not attracted to the smell of any anemones. Some of those raised with H. malu showed a response to BTAs but none showed a response to H. crispa, another natural host, or to H. malu. All of those raised with BTAs showed a very strong response to the smell of a BTA but none to H. magnifica, a natural host.

When these fish could see the host as well as smell it, those raised with with BTAs immediately went for BTAs but did not react to H. magnifica. Those raised with H. malu showed no reaction to BTAs or H. magnifica. Those raised without an anemone showed a weak response to BTAs.

These results back up the earlier study, but go a few steps further. They show that like A. ocellaris, naive A. melanopus have a weak but innate ability to recognize their most common host. Again, imprinting is key to host recognition. They also show that the fish can't be imprinted with unnatural hosts and that rearing them with such a host might actually interfere with their innate recognition. To quote this study:
"These findings are similar to the results of Arvedlund & Nielsen (1996) for the anemonefish A. ocellaris, which appears to imprint on its host anemone Heteractis magnifica, as well as having a genetic predisposition for olfactory recognition of this anemone... individuals of A. ocellans reared without an anemone did not acclimate to their host anemone Heteractis rnagnifica until 48 h after the start of the experiment. Am- started to acclimate on average after 28 min 35s. We therefore suggest that A. melanopus may have a stronger innate recognition of its main host than does A. ocellaris."

reefworm
01/02/2009, 12:29 PM
This is a great discussion! Thanks! I love it when an individual's tank-specific question leads to a scientific discussion. It's an education

paraletho
01/03/2009, 08:24 AM
+1 My favorite kind of thread. You usually get to see a couple of sides to the story. Literature is cited for you to check and see if you agree with conclusions. Very knowledgeable debaters with first hand experience. I don't have to hunt for any of the stuff. I'm basically a lazy scientist (LOL).