clam X prefers sand is bunk!

[mbbuna]

you always see people saying that squamosa, derasa and gigas "prefer" to be in the sand, why? because thats what they've read and were told, but its not true. when some writes that a clam "can" be found on the sand it doesn't mean that's where it is most commonly found. these clams are most commonly found right up on the reef.

when clams are planktonic they are at the mercy of the current, where they land they land and if the conditions are favorable they will live. a very tiny clam laying on the sand will get quickly covered and die. the only time you will find clams on sand is in very sheltered areas where the sand doesn't blow around.

there's a cool thread by a biology student(edr42) who's working on the GBR with lots of clam pics. heres a few i like

squamosa on the reef



gigas on the reef



derasa on the reef



so please think twice before you tell someone that such and such needs to be on the sand

[bassettmd]

mbbuna.... I agree with you largely on this whole matter. However, in the last pic of the derasa... does that clam have a secondary siphon on the left side of its mantle? Its hard to tell from the pic but that is what it looks like.

[Kalkbreath]

looks like a baby "Nessy" from Lockness.

or maybe its the elusive Derasa goby!

[Kalkbreath]

Its not that you dont find Deras or Gigas on hard reef structure....
Its that you don't find Maxima or Crocea on sand.
Its simply due to the bottom of the calms being different.
Clams with a foot are vulnerable to predators.
Its easy to tunnel under the sand and up into the byssal opening.
Derasa and Gigas have smaller openings or no opening at all.
Maxima and Croceas are setting ducks so to speak , when not tightly wedged into a rock depression.

[Kalkbreath]

The flip side is that while Gigas and Derasa can and do find themselves landing and settling on the reef itself, many times they out grow their location between corals or rocks and die. Since these type of clams don't or cant bore into rock like Crocea and Maxima .... once they run out of room to grow and they cant open their shell to expand they perish.
Out on the open sand a Gigas can grow to four feet. Something most impossible nestled within the reef.
Their inability to bore into rock and dissolve obstructions is of no concern.

[mbbuna]

Originally posted by Kalkbreath
Its not that you dont find Deras or Gigas on hard reef structure....
Its that you don't find Maxima or Crocea on sand.
Its simply due to the bottom of the calms being different.
Clams with a foot are vulnerable to predators.
Its easy to tunnel under the sand and up into the byssal opening.
Derasa and Gigas have smaller openings or no opening at all.
Maxima and Croceas are setting ducks so to speak , when not tightly wedged into a rock depression.

Kalk, your funny i read IBH on RDO every day, love how you try to twist the tide

not disputing that you cant find derasa, gigas or squamosa on sand. what im disputing is the "rock" clam "sand" clam thing, and where they are most commonly found. the reason isn't because of there byssal opening or being stuck in a rock

croceas and maximas are still subject to the same currents. they can and will settle on sand. but sand is dynamic, shifts, moves, burying any clam (unless in a very sheltered area). even in sheltered areas the sand will move, so a clam with a faster growth rate has a better chance of survival= no croceas and maximas

when any of the Tridacnids are very small there shell are almost indistinguishable from one another, all having wide byssal openings. the larger species of clams(gigas, derasa and squamosa) as they grow, rely on there weight to hold them in place. then byssal attachment atrophies and the shell closes in. when they are small and most venerable, all of the tridacnids are subject to the same sort of predation.

[Kalkbreath]

when they are small and most venerable, all of the tridacnids are subject to the same sort of predation.

....yes , but the longer you set in the sand, the more likely something will sooner or later crawl up your byssel.
there is solely one reason why certain clams bore into the rock.
Its to protect their vulnerable undersides.

[ezcompany]

i don't think its the "sole" reason. for croceas it may very well be the main reason, as they are the smallest and most vulnerable. other reasons for attaching/boring would be simply to stay put, and also be able to adjust themselves angle wise to the most favorable position towards the sun. i know my baby maximas move around the rock they are set in. the position changes frequently, like a hand on a clock, but it is still set on the flat piece of rock. my other baby maxima however refused to attach to rock, and would stay on substate, go figure.

[mbbuna]

Originally posted by Kalkbreath
....yes , but the longer you set in the sand, the more likely something will sooner or later crawl up your byssel.
there is solely one reason why certain clams bore into the rock.
Its to protect their vulnerable undersides.

NOPE!!

they attach themselves because they dont have the mass to hold them selves in place on there own. if the sole reason for attachment and boring into the rock was protection from predation they would have used that ability (growing new shell)to close the byssus in long ago.

borrowing into the rock helps keep them in place. the hole that a clam makes when it borrows isn't a tight squeeze. the same predators that can attack from the bottom can attack from the top. besides that, the major predators of clams in the wild will bore right through the shell or smother them with mucus.

anyway where did the classification of "sand clam" and "rock clam" come from?

[Kalkbreath]

The clam needs its foot for more then simply holding on...long after the clam has the size and strength to stay put in the wave action , the byssel opening must remain open so that the clam can continue to secrete calcium dissolving compounds through its foot. (Its the foot which dissolves the surrounding rock)
A boring clam has to continually dissolve the surrounding coral rock as it grows and to keep its opening from closing up. Many times the rock a clam has happened to have bored into is now live coral and this coral will try to out grow the clam. The clam must repeatedly dissolve the growing coral from around its lips and shell for the life of the clam. As it grows larger and larger the hole its in must become larger and larger

Its a trade off though, once a clam bores into the rock it cant escape, it cant change position or relocate.

That is not until some collector takes a hammer and breaks the rock to get the clam out.
We forget that in the wild clams like croceas are most often in bedded in rock up to the point that only their lips are sticking out of the rock.

[Kalkbreath]

I think its safe to say that no hobby clams prefer sand.
If you have a Gigas or Dersa in your tank, its a farmed clam and most farmed clams dont even know what sand is!
the great thing about farmed clams , other the their eco friendly status.....
is that farmed clams have no recollection of where their mother and fathers lived.
farmed clams spend their lives in shallow raceways on hard surfaces.
Domesticated clams are quite unlike their wild counterparts.
Many have never even felt sand on their tender byssel gands.
Derasa , Gigas and Maxima growing in the same conditions side by side at the same water dept and light exposer.
It matters little were wild clams can be found growing (sand or reef) if the clam in your tank is a domesticated farmed clam.
All Gigas and Derasa clams in the trade are farmed. (And thanks to recent progress... Maximas clams as well!)
Unless you purchase a really big farmed clam (six inched + ) your clam has been growing all its life under identical conditions as farmed maxima or crocea clam.
Farmers grow Maxima , Derasa and Gigas side by side in many raceways.
Many even share the same exact Zooxanthellae.
If a Derasa clam and a Maxima clam have lived all their lives side by side at the farm and even share the same zoxanthellae inside their veins...
It seems to reason more attention should be given to duplicating the conditions at the farm , then out on some ref in Australia.

[mbbuna]

i have know idea what you just said or what your point is

[Sk8r]

Well, not that I'm an expert on clams, but seems to me in the wild when you find one, you find a survivor. A hundred of its brothers may have become worm food, where they chose to lodge, but the crocea you find wedged in rock is the one that lived.

Mine, now, my sole crocea and my only experience with clams, has refused to stay in the rocks in both incarnations of this tank, though only in the second, with truly horrendous flow, does he form a real foot and at least attempt to hang onto rock. In both instances I have put this clam in the rock and tried to build him in, even, but he throws a fit and always propels himself to the same sandy portion of the bottom---more likely not that he rejects rock, but that the 'sunnier' area is the open glaring white sand.

[reefkoi]

My large clams simply won't fit up in the rockwork that space is valuable to me for SPS. I think a bunch of SPS on the sand would look stupid but a big gigas on the sand looks much better and seems happy to me. Maybe we should say "I prefer the clams to be on the sand"

[Kalkbreath]

Originally posted by mbbuna
i have know idea what you just said or what your point is

I guess to sum it up , When a hobbyists has a question about where he or she should place their new clam.( on the sand or on rock) I would like to point out something which is missing from the current pool of wisdom.....
This new perspective is : that regardless of what kind of clam a hobbyist may have just purchased ..... be it a Max , Dreasa, or Gigas.... if it is placed on the sand, it will be the first time that clam has ever found itself in sand!

(The exception might be larger farmed clams which are sometimes placed out in wire cages in sandy lagoons)

Farmed Gigas and Derasa clams are domesticated clams grown in farms far away from the reefs and sandy lagoons.
Even though the clams grandparents and great grandparents might have been found growing in a sandy lagoons.......This doesnt concern the little farmed raised clam because, currently all Gigas and Derasa clams finding their way to aquariums have been farmed on concrete.
Hobbyists are misled by being shown shown countless images of Gigas clams living in the wild in open sandy bottoms somewhere in Australia..
Because the clam they just purchased spent its entire life on a concrete raceway at a clam farm (ceramic tile) .

We should pay more attention to what the conditions were at the clam farm (where thier clam came from) , as apposed to how clams are found growing in the wild.

[jmaneyapanda]

Originally posted by Kalkbreath
IDomesticated clams are quite unlike their wild counterparts.
Many have never even felt sand on their tender byssel gands.

Hey kalk:

I know we have discussed before elsewhere, but I feel you are greatly flawed in calling these F1 captive clams "domestic". They are nowhere near domestic.

If these clams are so environmentally independant from their ancestors, why can't we propogate them in hyposaline conditions, in much lower light, in much higher (or lower)temperatures, etc? Using your logic, this should all be possible, becuase they dont remember their parents, and have no idea where they came from.

100 million years of evolution cannot be undone in 1 captive breeding.

Just my opinion.

[Kalkbreath]

These clams are adapted to life on a clam farm, not the ocean.

Call it what you will:but farmed clams have lived a domesticated life.

Call it "farmsticated" if it makes the scientific community happy.

But due to the fact that these hobby clams are headed towards an even future domesticated existence living in an aquarium. I kinda feel the public will more readily grasp the concept using my choice of lingo.

Farmed clams need to be in completely separate classification.
They are vastly different then their wild counterparts.

they need to be treated just like they have spent their days living out on the clam farm.

What happens in the nearby Ocean is for wild clam owners r to be concerned.



Wild clams need to be given a habitat which closely recreates the reef conditions at which the clam came from. But with such a vast difference in ocean reef conditions and the fact that one species of clam can be collected at ten feet of water or fifty feet.
Knowing just where your wild clam came from is mostly impossible.

Another case and point for buying farmsticated clams.
You will always be able to ascertain what conditions your farm clam likes!

[jmaneyapanda]

Originally posted by Kalkbreath
These clams are adapted to life on a clam farm, not the ocean.

Call it what you will:but farmed clams have lived a domesticated life.

Call it "farmsticated" if it makes the scientific community happy.

But due to the fact that these hobby clams are headed towards an even future domesticated existence living in an aquarium. I kinda feel the public will more readily grasp the concept using my choice of lingo.

Farmed clams need to be in completely separate classification.
They are vastly different then their wild counterparts.

they need to be treated just like they have spent their days living out on the clam farm.

What happens in the nearby Ocean is for wild clam owners r to be concerned.



Wild clams need to be given a habitat which closely recreates the reef conditions at which the clam came from. But with such a vast difference in ocean reef conditions and the fact that one species of clam can be collected at ten feet of water or fifty feet.
Knowing just where your wild clam came from is mostly impossible.

Another case and point for buying farmsticated clams.
You will always be able to ascertain what conditions your farm clam likes!

I agree wholeheartedly that farmed clams have been raised in an environment totally unlike wild clams, and have thus adapted to condition atypical of wild clams. However, I also disagree that this "wipes the slate clean" regarding requirement and characteristics of the species as a whole. If I am understanding you correctly, you feel these clams are so dependant on environmnetal variables during development, that such conditions can dramatically alter the species historic niche, despite their evolutionary past. This, I couldnt disagree with more. I dont understand why you are so willing to disregrad natural history in the face of adaptation. Yes, you may be able to grow derasas side by side with croceas in a farms raceway. But does this mean that Nature is bunk? No way- it means that the derasas are very tolerant. However, why doesnt this often happen in nature? Because their are other biological factors in play which leads to the species development as a whole. I am sure over the past several million years many clams that have been historically considered "low light" by hobbyists have ended up starting their life on the reef's upper limits, and many that are considered "high light" have eneded up in the sand far from the surface. Why haven't these individual proliferated and thrived? Why are cretain species found at certain depths and conditons in the wild while others are not? The short (and arguably vague) answer is because biological factors of nature have disalllowed it.

Overall, I think our opinuons are closer to each other than they appear. I, too, agree that captive rasied organisms are better suited to captivity, and can very well tolerate habitats and circumstances that the wild specimens might not be able to. But in the face of such events, I am absolutely ready to say that wild considerations are now to be disregarded- this is a gross misapplication of this process. These species are still subject to the same requirements of the wild specimens, and are still created by the millions of yeras of evolution, adaption, and selection. To disregard these principles in the face of indivdual animal tolerance certainly doesnt seem appropriate to me.

[mbbuna]

servers been down, missed all the fun.

the fact still remains that these clams that everyone categorizes as "sand clams" in the wild (not a concrete raceway) are most commonly found up on the reef.

[Kalkbreath]

Originally posted by mbbuna
servers been down, missed all the fun.

the fact still remains that these clams that everyone categorizes as "sand clams" in the wild (not a concrete raceway) are most commonly found up on the reef.

I agree.
Pretty much all baby clams in the wild are found "on" the reef. (not on the sand).
When was the last time someone documented (photographed) young Gigas or Derasa clams on the sand in the wild?(Mariculure not withstanding)

[Kalkbreath]

To disregard these principles in the face of indivdual animal tolerance certainly doesnt seem appropriate to me.

Part of what mbbunda and I are pointing out, is that there might not be as much difference as previously thought between the five species of clams.
Seems a closer examination of where young Gigas and Derasa clams spend their first five years (up in the reefs side by side with Maxima clams).....and the fact that clam farms seem to treat all species pretty much the same......Makes you wonder what the so called "experts" handing out clam advise over the past ten years were basing their positions on?

Also with regards to the terminology of "Domestication".
With such a poor choice of other words to describe wild animals now living a domesticated existence ..... "tame" or "pet" might work well to describe a house kitten or a family elephant working in India.
In the absence of better wording "domesticated" seem the best choice.
Are domesticated house cats really so different from wild cats?
Could one really tell an elephant working in India from one in the wild?
Even farmer Bobs domesticated pig if it escapes turns into a HOGZILLA.
Perhaps its the scientists were wrong about choosing to use the term domesticated to apply to genetic adaptations.(thats what the term "Variant" is for)

Animals which have changed psychologically and adapted to a domestic existence should equal "domesticated".

[mbbuna]

just having fun with wikipedia http://en.wikipedia.org/wiki/Domestication

i think the term is a little hard to grasp, there already is a good term to describe the "culturing" of clams, aqua-cultured

[mbbuna]

Originally posted by Kalkbreath

Seems a closer examination of where young Gigas and Derasa clams spend their first five years (up in the reefs side by side with Maxima clams).....and the fact that clam farms seem to treat all species pretty much the same......Makes you wonder what the so called "experts" handing out clam advise over the past ten years were basing their positions on?

its not just the first few years but there entire lives that they live there. yes, there are reports of SOME clams dislodging from the reef but i don't think its done on there own accord. i mean why would a clam that has been living in an ideal spot for X amount of time suddenly take a potentially life threatening gamble like that?

[mbbuna]

Originally posted by Kalkbreath
Makes you wonder what the so called "experts" handing out clam advise over the past ten years were basing their positions on?

i think much of the confusion about the term im talking about (sand clam) isn't comming from the experts/arthur's. its a misinterpretation of what they have written that continues to be perpetuated. remember when bristleworms were bad

BTW this was the point of me starting this thread. im not trying to get people to put there squamosas, derasas and gigas on the rocks, i just hope to maybe get people to stop using this baseless term "sandbed clam"

[mbbuna]

Originally posted by Kalkbreath


Animals which have changed psychologically and adapted to a domestic existence should equal "domesticated".

im assuming you mean physiologically? if so what physiologic changes do you think clams have made in there short stint of being cultured?

if you do mean psychologically, i must remind you that clams dont have brains