True or False? Anemones life span less than 2 year?

[phender]

I am pretty much agreeing with both sides at this point.

My main gripe is similar to Bonsainut's, that is once something gets printed, it becomes an assumed fact and then gets misrepresented. I have already seen many articles/posts stating that anemones should not be kept because wild anemones are 100s of years old. There is a whole boat load of reason's that we should cut down on the number of anemones being taken from the wild, but every wild anemone being 100 years old isn't one of them.

The main reason I did my survey and article in the first place was that every article and book at the time that talked about keeping anemones said that "sebae" anemones were very easy to keep. Turns out most of the people writing these articles and books had never kept sebae anemones, they were just parroting a previous article. Since there weren't many anemone articles in those days, that bad info really got around. Actually most advanced anemone keepers in fact were not able to keep sebaes, especially the bleached ones. Similar misinformation being quoted over and over has become one of my pet peeves.
I'm not saying the "live for 100 years" thing is wrong, but it is very often misrepresented.

 

[WDLV]

Well put. I get that this is a pet peeve for at least two of the contributors of this thread. There are some very good points made and I understand why it bothers you. I will say however that I'm a little surprised that neither of you have followed this to what I feel is a logical conclusion... that is to write an article or at least a thread that can be stickied for posterity. A 'Anemone Life Span - Dispelling The Myths' kinda thing. It won't eliminate the idea that it is a norm for all host anemones to live for hundreds of years, but it might in time at least be held in the same reverence as your (Phil) previous article.
If it were to come in the form of an article you'd obviously want to cite crediable sources to support your belief but if it were in the form of a sticky thread, it could be done casually with more generalizations.
...or have you already done this?

Either way, I've gained a lot out of this thread. I never gave this particular aspect much thought before now and just sort of took it for granted that anemones were naturally long lived. Now I have a better idea why in some cases that might be true and why in others it may not.

 

[BonsaiNut]

I will say however that I'm a little surprised that neither of you have followed this to what I feel is a logical conclusion... that is to write an article or at least a thread that can be stickied for posterity.

I will attempt to provide at least some insight, though it may take a while. There are plenty of field surveys that point to high rates of mortality among sea anemones in the wild, which are inconsistent with the idea that sea anemones are hundreds of years old...

The symbiosis between giant sea anemones and anemonefish on coral reefs is well known, but little information exists on impacts of this interaction on the sea anemone host. On a coral reef at Eilat, northern Red Sea, individuals of the sea anemone Entacmaea quadricolor that possessed endemic anemonefish Amphiprion bicinctus expanded their tentacles significantly more frequently than did those lacking anemonefish. When anemonefish were experimentally removed, sea anemone hosts contracted partially. Within 1–4 h in most cases, individuals of the butterflyfish Chaetodon fasciatus arrived and attacked the sea anemones, causing them to contract completely into reef holes. Upon the experimental return of anemonefish, the anemone hosts re-expanded. The long-term growth rate and survival of the sea anemones depended on the size and number of their anemonefish. Over several years, sea anemones possessing small or no fish exhibited negative growth (shrinkage) and eventually disappeared, while those with at least one large fish survived and grew.

The pest anemone Aiptasia is notorious for its ability to asexually reproduce, and to take over closed systems in a short period of time. Yet no one seems to wonder why Aiptasia does not cover the reefs of the world. Clearly something is causing a high rate of mortality for this species that is keeping its numbers in check. Removal of this limiting factor would tend to demonstrate the ability of asexually reproducing anemones to quickly reproduce out of control.

Continuous carpets of the anemone Aiptasia sp. were recorded on vast areas of shallow reef platforms along the eastern shore of Fernandina Island in December 2000 and March 2001. The Aiptasia sp. carpets have replaced diverse assemblages of algae, invertebrates, and fishes that once characterized these platforms. Virtually the only other mega-invertebrate that persists in these areas is the pencil urchin Eucidaris thouarsii. Patches of the alga Padina sp. are occasionally present, although somewhat covered with Aiptasia sp. anemones. Fishes are very low in abundance and diversity. Hence, we describe the anemone-dominated habitat as anemone barrens... ...The holothurian Stichopus fuscus is a suspected predator of Aiptasia in the Galapagos because Bermeo-Sarmiento (1995) found 'cnidarian polyps' in this benthic-feeder's gut. Holothurians like Stichopus fuscus are more likely to inhabit open habitats because of their chemical and other defenses, but a very intense sea cucumber fishery (Okey et al. 2002) has considerably reduced this species throughout the Galapagos concurrently with the appearance of the anemone barrens.

Other examples of anemones "taking over" ecosystems abound. When environments are disturbed, or predators are removed, anemones can quickly become pests. High rates of reproduction do not normally correlate with long life - they are typically correlated with high rates of mortality and short life.

There are other examples around the world of clones spreading over small to large areas, usually in sheltered reef habitats... ...At Moorea, Society Islands, the anemone Heteractis magnifica covered very large areas of reef until cyclones broke up the anemone fields into small patches (D. Fautin, pers. comm.). Similarly, on a fringing coral reef at Eilat in the northern Red Sea, the corallimorpharian anemone Rhodactis rhodostoma covered up to 69% of the inner reef flat after a catastrophic low tide in 1970 partially caused by consecutive days of strong wind from the north (Chadwick-Furman and Spiegel 2000). They suggested that this species has become an alternative dominant species replacing stony corals in that system.

I will dig around and try to pull something together. Unfortunately it will take me some time to get access to some of the research - I have to work through third parties sometimes to get papers.

 

[jsharp1]

Although we have managed to go slightly off topic here, I think the spirit in which this thread was started is still relavent.... If you really want to know what the life span is in captivity for anemones, do an advanced search in Google. Put "www.reefcentral.com" in the domain field and the words "help" and "anemone" in the word search field and see what you come up with. The point being that you can easily do a survey on anemone survival rates in captivity just by reading the outcomes on this site. Most result in death in the first few weeks or months....

The ones that don't start with "help" in the title start out with 'lookey here' and end up with warnings about bleached specimens and either they die or you never hear from the original poster again.
Then there are those who are skilled and those who are lucky. Those are the threads that get the most hits and (I think) contribute to the beginner thinking these animals are reasonable to keep one month into the hobby. They don't want to read about the guy who is struggling to keep one alive, though those threads often have very good advise about both what to do and what not to do.

It's nice to see the different views that's why I like to read/post on here As far as the article goes, I definitely don't take everything I read as fact. Whether or not wild anemones live for hundreds of years or captive anemones live for less than 2 years, I really don't know. The reason I posted the article is because I thought it would be interesting to hear what the more successful anemone keepers thought of this. I like to read about the different experiences that people in this hobby have had with keeping their nems. So, I guess I'm saying that I am not so much interested to know if the survival rate of captive nems is more or less than 2 years, but I am more interested in the reasons behind why they have or haven't survived and to hear from those who have successfully kept a nem for more than a couple of years. Lol, I hope I'm making sense!

 

[tufacody]

I agree that the beauty of this thread is that it thrives on scientific process, or the elimination of other factors before reaching a conclusion.

With that said, I view this topic as similar to evolution. Not all the answers are in, but that doesn't make the scientific process any less faulty. For the most part, I think that the thesis that anemones can live for decades or longer has good support.

For those who have been lucky enough to keep nems long term, we tend to notice something interesting - the tissue just shows no signs of aging, nor do their behaviours change with age. This is fairly unique in the animal kingdom. If these things do age, it appear to take longer than our lifetimes to notice it.

 

[BonsaiNut]

It's nice to see the different views that's why I like to read/post on here As far as the article goes, I definitely don't take everything I read as fact. Whether or not wild anemones live for hundreds of years or captive anemones live for less than 2 years, I really don't know. The reason I posted the article is because I thought it would be interesting to hear what the more successful anemone keepers thought of this. I like to read about the different experiences that people in this hobby have had with keeping their nems. So, I guess I'm saying that I am not so much interested to know if the survival rate of captive nems is more or less than 2 years, but I am more interested in the reasons behind why they have or haven't survived and to hear from those who have successfully kept a nem for more than a couple of years. Lol, I hope I'm making sense!

LOL Jsharp - you started quite a thread

I guess you could say the following:

(1) No one knows the actual age of any anemone in the wild. There is evidence to suggest some may be quite long-lived, while others may be only a few years old and appear identical. There is evidence to suggest that anemones have the POTENTIAL to live a long time - assuming perfect conditions and lack of predators.

(2) For the anemones that we are interested in (clown anemones), long term survivability, growth rates, and size are positively correlated with the presence of two or more clownfish. Anemones without clownfish tend to shrink and/or disappear. Anemones with clownfish are much more likely to survive and thrive.

(3) Clown anemones have been grown from eggs to large individuals in three years, so being large (by itself) is no indication that an anemone is any older than three years old. Conversely, just because an anemone is small does not mean it is young. Size of an anemone is more correlated with environmental conditions than age.

(4) Mortality of anemones in the wild is no indication of mortality in captivity. Anemones tend to be poor shippers and difficult to acclimate. Additionally, they tend to have specific environmental requirements that are not always met by aquarists. Once established in an appropriate tank, anemones tend to be long-lived. In fact, there are plenty of examples of anemones living in captivity for much longer than the two years in your question.

I tried to stay true to the facts

The keys to anemone success:

(1) Start with a healthy individual.

(2) Provide a proper environment for the species - don't round corners and try to get by with not enough light, not enough water movement, etc.

(3) Provide clownfish. Not required, but numerous studies have been done on the nutritive benefits clowns provide host anemones.

(4) Keep your system stable. Once anemones are established, they can be hardier than many other tank invertebrates and can survive system failures that kill other critters (temp drops, loss of electricity, etc). However changes to the system appear to be the primary cause of death once an anemone is established in a tank. This includes things like (a) introducing a different, sick anemone, (b) feeding bad food, (c) introducing unintentional predators (worms, butterfly fish, crabs, shrimp, large angels, etc), (d) doing a major system change with new lights, new filters, etc... and the list goes on. Once you find a formula that works, stick to it and don't introduce changes.

 

[WDLV]

I will attempt to provide at least some insight, though it may take a while.

That would be great. Even if I retort. LOL

I have thoroughly enjoyed this thread.

 

[jsharp1]

Lol, your makin him do his homework!

 

[WDLV]

Nah. I think he already has his #### straight.

 

[bues0022]

Wow, I haven't looked at the thread for a few days and it goes crazy! My hat goes off to all contributors of this thread being able to discuss this topic with so much objectivity and openness without it degrading into name-calling and bashing. This has been a good read!