SoccerPro522
Reefing newb
This probably a dumb question but can tiger tail sea cucumbers release toxins into the water. I was reading about them online and there is mixed results some say they do some say they dont:frustrat:
Tiger Tail Cucs
- Thread starter SoccerPro522
- Start date
BL1
.............
I've been told they're safe. I'm hoping that's right, I got 2 in my CUC package
supernatureal
Reefing newb
If and when they die they can release toxins into your tank and kill everything kind of like an anenome.
daugherty
part time reefer
yes they are good until they get very stressed they can expell their insides and die with is bad for the tank. but they are good animals to have in the tank you will just have to keep an eye on them
BL1
.............
an except from http://www.advancedaquarist.com/issues/jan2003/invert.htm
I would not be doing anyone a favor if I did not point out that most popular aquarium texts have dire warnings about the dangers of including one of these animals in your reef tank (e.g., Delbeek and Sprung 1994a; Delbeek and Sprung 1994b; Fenner 1998; Paletta 1999; Tullock 1997). So why is it that these animals are so feared by many aquarists? Well, the simple answer is that when they are injured in the aquarium, some of these species are capable of releasing a toxic chemical soup that can poison an aquarium (reviewed by Paul 1992; Pawlik 1993). The possibility of having one of these animals poison an aquarium (commonly called a ‘cuke nuke’ on the internet) is enough for many people to shy away from ever adding one of these animals to their aquarium. However, I think that this fear is somewhat misplaced. I’d like to take a bit of time to explain the chemical defenses of sea cucumbers in some detail and hopefully dispel some of the myths surrounding these animals. Let’s start at the beginning: when a sea cucumber is stressed, it can react in a variety of ways. First, like other echinoderms, they have a compound in their skin called catch collagen - this tissue is under neurological control and is capable of changing from a 'liquid' to a 'solid' form very quickly (Brusca and Brusca 1990; Motokawa 1984a; Motokawa 1984b; Ruppert and Barnes 1994). This is one of the coolest things about echinoderms in general, and is one of the reasons that this group has been so successful. The ability of the catch collagen to change from liquid to solid form at will is how sea cucumbers manage to get themselves into such tiny holes in the live rock structure - they are able to ‘goopify’ their bodies (for lack of a better description), literally pour themselves into the hole they have chosen, and then solidify their skin to prevent anything from being able to remove them (Motokawa 1984a; Motokawa 1984b). The same is true of how urchins move and ‘lock’ their spines, or how sea stars can exert continuous pressure on a clam to slowly pry it open without getting tired, and so on. Sorry, I guess I’m getting off track... OK, so as I just said, the cucumber can change its consistency, and many react to stress by either becoming flaccid and goopy, or by ejecting all the water from its system and becoming a small, hard turd-like lump (at least that seems to be the description I hear most often from the spouses of aquarists who own a sea cucumber). Either of these responses is typical of animals that have been moved between tanks or harmlessly disturbed (e.g., poked with a finger, nipped by a fish or such).
A second and more drastic response is evisceration - the violent expulsion of the gut I mentioned above. In this case, the cuke basically expels a portion of its digestive system (guts) onto the substrate. It may be the fore or hind gut depending on the species in question, and may or may not be a serious trauma to the cucumber (Ruppert and Barnes 1994). Evisceration can be induced in a variety of ways (including such factors as chemical stress, physical manipulation, crowding, etc.), and in some species, every individual in the population appears to be at the same stage of regeneration, suggesting that evisceration may be a normal seasonal phenomenon in some species (Ruppert and Barnes 1994). It is unclear why individuals go through the evisceration, but possible explanations include periods of inactivity when food is naturally rare, or the elimination of toxic wastes that have accumulated in the internal tissues (Ruppert and Barnes 1994). Whatever the cause, this ‘puking your guts out’ response usually includes some or all of the digestive system (and in some cases other organs such as the respiratory tree and gonads), but is not necessarily accompanied by chemical discharge (Brusca and Brusca 1990; Ruppert and Barnes 1994). Because there is not necessarily any chemical discharge that accompanies evisceration, even a highly stressed sea cucumber that ejects its intestines may not have much of an impact on your aquarium, depending on the situation. Despite the fact that this stress response may not wipe out your tank, it is certainly not trivial to the sea cucumber – the cuke loses its digestive capacity in the process and although it can regenerate the gut, it needs time, rest, and excellent water conditions to do so. If the cucumber was stressed enough to eviscerate in your aquarium in the first place, chances are slim that conditions are ideal for them to regenerate their gut, either.
The final and most drastic response possible is when a stressed cuke expels its Cuvierian tubules. These tubules are a series of long, spaghetti-like tubes which are associated with the hind gut of certain sea cucumbers, and are thought to be primarily defensive in function. Not all species possess these defensive structures, and even those that do, generally do not eject them without dire provocation. The Cuvierian tubules are located near the anus, and branch off from the base of the respiratory tree (the branched ‘gills’ of a sea cucumber). Now, if you’re reading this carefully, you should be wondering why the ‘gills’ of a sea cucumber are so near to its butt. Well, the answer is simple, although unusual – sea cucumbers actually breathe through their anus! That’s right – many people make the mistake of watching a sea cucumber breathe (it is quite obvious as the anus opens to allow water to flow in and then pinches down as the animal ‘exhales’ the water it just ‘inhaled’) and thinking that the opening that they are watching is the mouth. In cucumbers however, respiration is done through the anus, and the respiratory tree is associated with the other end of the digestive system. Why does any of this matter? Because when a cucumber is really threatened (it thinks it is about to be eaten), it can respond by inhaling a bunch of water and physically rupturing (literally exploding) the hind gut to expel these tubules and a soup of defensive chemicals that are intended to prevent the predator from ever wanting to mess with a sea cucumber again. The amount of defensive chemistry and the specific combination of chemicals that are produced varies by species from just under two to nearly three and one-half percent of the dry weight of the cucumber (Bryan et al. 1997). In general, the chemicals which appear to protect the sea cucumbers from being eaten are saponins (soap-like compounds) which are derived from triterpenoids (Ponomarenko et al. 2001; Stonik and Elyakov 1988). These chemicals usually work well to discourage many generalist predators, and unfortunately are also likely to seriously impact, and potentially even wipe out all their tankmates in a reef aquarium (the so-called ‘cuke-nuke’).
In general, it is probably reasonable to say that sand-feeding turd cukes are less toxic than the colorful filter feeders, or more specifically, the concentrations and variety of toxic chemicals found in the Aspidochirotiacea – the group that contains the sand-feeding cucumbers – is generally lower than those of the Dendrochirotacea – the group that contains most of the colorful suspension feeding cucumbers (Paul 1992; Pawlik 1993).
Sea cucumber defense responses
A second and more drastic response is evisceration - the violent expulsion of the gut I mentioned above. In this case, the cuke basically expels a portion of its digestive system (guts) onto the substrate. It may be the fore or hind gut depending on the species in question, and may or may not be a serious trauma to the cucumber (Ruppert and Barnes 1994). Evisceration can be induced in a variety of ways (including such factors as chemical stress, physical manipulation, crowding, etc.), and in some species, every individual in the population appears to be at the same stage of regeneration, suggesting that evisceration may be a normal seasonal phenomenon in some species (Ruppert and Barnes 1994). It is unclear why individuals go through the evisceration, but possible explanations include periods of inactivity when food is naturally rare, or the elimination of toxic wastes that have accumulated in the internal tissues (Ruppert and Barnes 1994). Whatever the cause, this ‘puking your guts out’ response usually includes some or all of the digestive system (and in some cases other organs such as the respiratory tree and gonads), but is not necessarily accompanied by chemical discharge (Brusca and Brusca 1990; Ruppert and Barnes 1994). Because there is not necessarily any chemical discharge that accompanies evisceration, even a highly stressed sea cucumber that ejects its intestines may not have much of an impact on your aquarium, depending on the situation. Despite the fact that this stress response may not wipe out your tank, it is certainly not trivial to the sea cucumber – the cuke loses its digestive capacity in the process and although it can regenerate the gut, it needs time, rest, and excellent water conditions to do so. If the cucumber was stressed enough to eviscerate in your aquarium in the first place, chances are slim that conditions are ideal for them to regenerate their gut, either.
The final and most drastic response possible is when a stressed cuke expels its Cuvierian tubules. These tubules are a series of long, spaghetti-like tubes which are associated with the hind gut of certain sea cucumbers, and are thought to be primarily defensive in function. Not all species possess these defensive structures, and even those that do, generally do not eject them without dire provocation. The Cuvierian tubules are located near the anus, and branch off from the base of the respiratory tree (the branched ‘gills’ of a sea cucumber). Now, if you’re reading this carefully, you should be wondering why the ‘gills’ of a sea cucumber are so near to its butt. Well, the answer is simple, although unusual – sea cucumbers actually breathe through their anus! That’s right – many people make the mistake of watching a sea cucumber breathe (it is quite obvious as the anus opens to allow water to flow in and then pinches down as the animal ‘exhales’ the water it just ‘inhaled’) and thinking that the opening that they are watching is the mouth. In cucumbers however, respiration is done through the anus, and the respiratory tree is associated with the other end of the digestive system. Why does any of this matter? Because when a cucumber is really threatened (it thinks it is about to be eaten), it can respond by inhaling a bunch of water and physically rupturing (literally exploding) the hind gut to expel these tubules and a soup of defensive chemicals that are intended to prevent the predator from ever wanting to mess with a sea cucumber again. The amount of defensive chemistry and the specific combination of chemicals that are produced varies by species from just under two to nearly three and one-half percent of the dry weight of the cucumber (Bryan et al. 1997). In general, the chemicals which appear to protect the sea cucumbers from being eaten are saponins (soap-like compounds) which are derived from triterpenoids (Ponomarenko et al. 2001; Stonik and Elyakov 1988). These chemicals usually work well to discourage many generalist predators, and unfortunately are also likely to seriously impact, and potentially even wipe out all their tankmates in a reef aquarium (the so-called ‘cuke-nuke’).
In general, it is probably reasonable to say that sand-feeding turd cukes are less toxic than the colorful filter feeders, or more specifically, the concentrations and variety of toxic chemicals found in the Aspidochirotiacea – the group that contains the sand-feeding cucumbers – is generally lower than those of the Dendrochirotacea – the group that contains most of the colorful suspension feeding cucumbers (Paul 1992; Pawlik 1993).
BL1
.............
Wow, I didn't realize how long that was when I was copying and pasting. It was a good read though, I'm still glad to have my sea cucs
