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( Intro; This is a very interesting follow- up article arising from Malcolm Short's "Angels At Christmas". Gerry gives us food for thought before buying as well as very useful tips on sexing Angels. On reading it, I found just how little I knew about how to sex Angels! I hope you find his article as enlightening as I did.) How pleasing it was to read Malcolm Short's article "Angels At Christmas" which appeared on the Ryedale Aquarist website, accompanied by some excellent photographs. Obviously, from what Malcolm explained, the initial object of the exercise was to obtain, albeit at his wife's prompting, a second Angel as a companion for what she felt may otherwise become a lonesome inmate, rather than a serious attempt to propogate the species. The fact that the two fish subsequently turned out to be a pair is truly remarkable. I remember an undergraduate from Loughborough University working out that in order to guarantee ending up with a pair of fish in a species where sexing is difficult, it would necessitate obtaining no less than 8 speciemens. Obviously, unless the aquarist is intent on breeding this large growing specie and has the space to house such a number, it would be unwise to embark on such an undertaking. Buyer beware!.... Immature Angels in dealers' tanks do present themselves as an inviting proposition, so I can appreciate why they assume the "irresistible purchase" tag. Sadly what most inexperienced aquarists fail to consider as they re-stock their tank, is that Angels are a large growing specie. Within a few months they may well have reached a length of 15cms (6"), by which time, the 8 speciemens, especially if housed with other inmates will have outgrown a four foot tank and incidentally could well be responsible for the disappearance of some of the smaller growing cousins in their environment. Sexing Angels-; Of the most popular aquarium favourites, Angels are certainly one of the most difficult to sex, if not the most difficult. Over the years there have been four "foolproof" methods of sexing near mature Angels and maybe a dozen or so "tried and tested" methods which I will describe briefly. Perhaps the oldest method being the practice known as "candling". This involves transferring the fish to a smaller container and then, in a darkened room, placing the fish in front of a small but strong light so that the internal organs could be seen. (A sort of do it yourself x-ray). From the positioning and shape of the organs, the author claimed that the sex could be determined. The second method was much simpler in that it merely involved visual appearance, head on of the lower body shape immediately in front of the anal fin. The male would appear "v" shaped, whilst the female would be "u" shaped. The third method claimed that immature specimens could be assessed by the angle at which the first ray of the anal fin left the body. If this angle is at 90 degrees to the body then the fish is a female, whereas if the ray slopes backwards towards the caudal peduncle, then it is a male. The fourth and last method is the least reliable of them all, although logically it may seem the most natural. This involves allowing your specimens to form pairs themselves, which you will find they will readily do. Over the years I have had many instances where I have found two angels cleaning their proposed spawning site only to find subsequently that the spawning ritual was being carried out by two females! Now to some of the other methods;- (1) There is a noticeable difference between the sexes in the first short rays of the dorsal fin. (2) The distance between the ventral and anal fins differs between males and females. (3) The angle of that portion of the body in number (2) is an indication to the sex. (4) Excreta leaves the male in a forward direction whereas in females it emerges in a backward direction. These then are some of the desperate ways our forebearers used in the struggle to sex one of the most popular specie of tropical fish. I wouldn't give any credence to any of the latter examples personally. However, the one thing I would derive from number (4) (and this applies to all species, not just Angels) is that if excreta is visible to that extent, then the fish is suffering from constipation and a change of diet should be administered. Having had over 40 years experience in the breeding of these aquarium favourites of mine, I can assure readers that not one of the four "foolproof" methods is infallible in the sexing of Angels. Whilst I will readily concede some limited success may be experienced when using any one of the first three methods, don't be lulled into believing that your chosen method works for you;- it probably did but this was nothing more than luck. The only way to guarantee the true sexes of your Angels, is to observe them when the ovipositor is extended during spawning. Females will be seen to possess a straight sided tube roughly 3 mm in length, down which the eggs pass, whereas males have a cone shaped tube which is much narrower at its outer extremity than it is where it emerges from the body. The tubes can often be seen some hours prior to spawning so there is no rush to try to identify which is a cone and which a tube. Even an absolute novice will be able to distinguish the difference between the two once they are lowered. Feeding new Angel fry..... In his article, Malcolm goes on to say that he lost many young fry in their early stage. I suspect the reason for this being that they drowned due to the type of food being fed. I am a great believer in Liquifry, but unfortunately a similar outcome would have been experienced even if the egglayer variety had been available. Whilst this type of infusoria is an excellent first food for most species, it does not suit Angels as it apparently blocks the gills. Another first phase food which I have found unsuitable is microworm. Angels are gulp feeders and as they swallow the microworms the small barbs on the tails of the worms rips the throat lining which results in heavy losses. It is heartbreaking to find that a large spawning suddenly reduces by say 50%, when you believe you are doing your best to rear them. Without doubt Malcolm saved many fry by feeding them finely ground dry food, but I would recommend that if he does go on to set up a breeding programme that he considers using newly hatched Brine Shrimp as a first food. I have always found that my fry will take this nutritious food as soon as they become free swimming and go on from strength to strength. Summary Gerry's article first appeared in the "Ryedale Reporter". (The now almost infamous "good read" which is produced monthly by David Marshall for Ryedale A.S.) My thanks to Gerry for his informative article and also to Malcolm for agreeing to allow Gerry to write a follow up article, which points out where Malcolm made mistakes! However, I do feel that this is what fish keeping and breeding is all about, because if we didn't have this "exchange" our hobby would be all the poorer for it. Copyright; Text; Gerry Hawksby. Photo; Malcolm Short |
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