Florida Gars suddenly have wierd "flaking" on their scales and possibly blood.

[E_americanus]

i think her point is that you are not going to look at a group of gar and be able to pick out the males and females (especially w/ out knowing any backround info on the fish). even on wild gar, size is not a surefire way to sex them.

in the wild, however, if they are past a certain size, there is a very high probability that one could sex them based on size, especially longnose, shortnose, spotted/Florida. females tend to get a decent amount larger whereas males generally slow down/stop around a certain point.

as richard said, this has been well documented in the literature.

either way, at 14", size won't be an issue in sexing these two gars, as they are both somewhat stunted at this point (pretty much inevitable in the home aquarium to an extent), so the only way to figure out what they are would be to get some other Florida/spotteds and see if they will spawn (assuming we're ruling out invasive procedures)--
--solomon

ps-- but congrats again, these have got to be some of the oldest Florida/spotteds i've heard of in the home aquaria in recent history

 

[nerfkhat]

that is the jack dempsey. i had a jack and a dwarf snakehead and the jack plucked him dry of his scales and my snakehead died.

 

[Polypterus]

in the wild, however, if they are past a certain size, there is a very high probability that one could sex them based on size, especially longnose, shortnose, spotted/Florida. females tend to get a decent amount larger whereas males generally slow down/stop around a certain point.

I never said "surefire" what I said was there is documentation that exists that clearly indicates a size / weight/ growth disparity that could hypothetically be used to sex these fish in captivity.

Various studies have used a form of discriminate analysis to determine gender externally. In one such study (Johnson 1997), a series of known morphometric traits are taken and then plugged into a formula. Using this outcome, if the results are 75% or more matching, there is a high probability of that fish being male or female. This has been shown to be very accurate as far as non-destructive practices go and is a tested and accepted method in doing field work with lepisosteids.

There is no reason that if correct data is known that the same general idea could not be applied to captive lepisosteids.

This is why I prefer to not say this can not be done and that in no way can you sex a gar externally. You can likely do so, what is required however is the data. At this time that data is insufficient.

(Johnson, B.L., Noltie, D.B. 1997. Migration and Population dynamics of stream-spawning Longnosed gar (Lepisosteus osseus). Transactions of the American fisheries society 126:438-466)

 

[demjor19]

in the wild, however, if they are past a certain size, there is a very high probability that one could sex them based on size, especially longnose, shortnose, spotted/Florida. females tend to get a decent amount larger whereas males generally slow down/stop around a certain point.

as richard said, this has been well documented in the literature.

either way, at 14", size won't be an issue in sexing these two gars, as they are both somewhat stunted at this point (pretty much inevitable in the home aquarium to an extent), so the only way to figure out what they are would be to get some other Florida/spotteds and see if they will spawn (assuming we're ruling out invasive procedures)--
--solomon

ps-- but congrats again, these have got to be some of the oldest Florida/spotteds i've heard of in the home aquaria in recent history

im not trying to stir you guys up by arguing, but my basic point was that in AQUARIA a large majority of people just dont have the basic backround info to be able to take an educated guess at the sex of their fish. this methode may be a very solid methode in the field, but in aquaria i just dont see it holding up...maybe if you had a very large aquarium that could eliminate stunting and provided a closer to natural habitat.

a little off topic...but what are the requirements to make this (highlighted in red) happen in the home aquaria and if your setup meets these requirements...what are the odds they could spawn (assuming you have a mature male/female pair)?

 

[Polypterus]

im not trying to stir you guys up by arguing, but my basic point was that in AQUARIA a large majority of people just dont have the basic backround info to be able to take an educated guess at the sex of their fish. this methode may be a very solid methode in the field, but in aquaria i just dont see it holding up...maybe if you had a very large aquarium that could eliminate stunting and provided a closer to natural habitat.

a little off topic...but what are the requirements to make this (highlighted in red) happen in the home aquaria and if your setup meets these requirements...what are the odds they could spawn (assuming you have a mature male/female pair)?

Not really arguing with you Jordan (And Kara too) more of trying to add something interesting so I have a reason to not just slice my wrist and give up entirely with the idea that detailed information can be discussed here...
Cookie cutter / Chuckee-Cheeze responses to everything is getting old. I think some of us are adult and knowledgeable enough to delve into more detailed aspects of Gar biology that includes such things as References and big words. If this frightens off some so be it....

You are correct in that most are not aware of, Do not have access to, nor do they care to look for information regarding their fish to do what it is I'm stating. But it is there and it would be desirable for others to see it or be able to look for it rather than just blanketly say "it can't be done". Serious gar keepers / researchers are few and far between and our network is small. A good number of us have recognized each other through outlets such as this. This being the case it is advantageous to keep above constant Chipmunk chatter from time to time...

IMO, based on the data I've seen, I'm not all that hopeless on a system that would use morphometric traits to sex sub-adult / Adult age gar in captive conditions. The work being preformed with Atractosteus tropicus in Mexico is proving to be very promising in regards to this.

There really is minimal stunting in Florida / spotted gars in aquaria and the average data that is known on them seems rather constant and comparable to fish in the wild. Some morphologic characteristics however seem to be skewed for a yet unknown reason (lots of theory abound here). Snout growth for instance, seems to not want to fit in with the formula for wild gars but does seem rather constant enough in captive ones so as to be within a set of expected variables.

a little off topic...but what are the requirements to make this (highlighted in red) happen in the home aquaria and if your setup meets these requirements...what are the odds they could spawn (assuming you have a mature male/female pair)?

So far only a few successful spawnings of these fish have occurred in Aquaria, without the addition of hormones. Cases have been different in each case. The best documented was by Hiroshi Azuma (T.F.H. August 2002 issue).

I believe it is very possible to spawn these fish in aquaria. Many also poo poo'ed being able to spawn Polypterids and Potamotrygonidae... Both families, now that a protocol has been developed, have been spawned regularly... Much of the foot work (like that I'm talking about often) has not yet been done with Lepisosteids. This situation however is rapidly changing as a growing number of serious individuals are now devoting significant time and energy towards doing just this...

It is a goal to develop a protocol for the Aquaria spawning of various Gars and I am not pessimistic about this taking forever....

 

[demjor19]

Not really arguing with you Jordan (And Kara too) more of trying to add something interesting so I have a reason to not just slice my wrist and give up entirely with the idea that detailed information can be discussed here...
Cookie cutter / Chuckee-Cheeze responses to everything is getting old. I think some of us are adult and knowledgeable enough to delve into more detailed aspects of Gar biology that includes such things as References and big words. If this frightens off some so be it....

You are correct in that most are not aware of, Do not have access to, nor do they care to look for information regarding their fish to do what it is I'm stating. But it is there and it would be desirable for others to see it or be able to look for it rather than just blanketly say "it can't be done". Serious gar keepers / researchers are few and far between and our network is small. A good number of us have recognized each other through outlets such as this. This being the case it is advantageous to keep above constant Chipmunk chatter from time to time...

IMO, based on the data I've seen, I'm not all that hopeless on a system that would use morphometric traits to sex sub-adult / Adult age gar in captive conditions. The work being preformed with Atractosteus tropicus in Mexico is proving to be very promising in regards to this.

There really is minimal stunting in Florida / spotted gars in aquaria and the average data that is known on them seems rather constant and comparable to fish in the wild. Some morphologic characteristics however seem to be skewed for a yet unknown reason (lots of theory abound here). Snout growth for instance, seems to not want to fit in with the formula for wild gars but does seem rather constant enough in captive ones so as to be within a set of expected variables.



So far only a few successful spawnings of these fish have occurred in Aquaria, without the addition of hormones. Cases have been different in each case. The best documented was by Hiroshi Azuma (T.F.H. August 2002 issue).

I believe it is very possible to spawn these fish in aquaria. Many also poo poo'ed being able to spawn Polypterids and Potamotrygonidae... Both families, now that a protocol has been developed, have been spawned regularly... Much of the foot work (like that I'm talking about often) has not yet been done with Lepisosteids. This situation however is rapidly changing as a growing number of serious individuals are now devoting significant time and energy towards doing just this...

It is a goal to develop a protocol for the Aquaria spawning of various Gars and I am not pessimistic about this taking forever....

i hear you as far as the typical post goes. it does tend to get old from time to time, but i guess if it helps others then that is what matters...

to be honest i have always suspected that stunting was fairly common in most gar species. so i was a bit surprised when you said that most of them are not stunted. does this mean that most of the florida/spotteds you encounter in the field average about 18-24 inches as adults? i have not yet had the privlege to do any gar field research so im not very familiar w/ captive vs wild size differences...maybe this spring/summer i will get the chance to go?

so...back to sexing. if you see a fish that is suspected to be of adult size/age and raised in proper conditions would you be able to give a fairly solid guess as to what the sex is?

you know i'm never affraid to get into a good "indepth" discussion.

 

[KaraJo]

so...if you can go out and catch some wild Florida gar, and try to get an educated guess as to males and females, you could possible have a good cahnce of catching a pair?? Then, placing them into a few thousand gallon tank or aquarium together to breed. Only problem is getting them to actually do it, but to me this seems to simple without being done readily. I feel taking them out of their natural habitat would mess with their spawning cycles. If/when given the opportunity to do this, I think we would try it out and see what happens. Nothing is for sure to happen, but just like with our female black Rhom being one of few to have ever laid eggs in captivity, and it being unheard of for them to breed, nothing is impossible, and with the funds, even breeding them would be something I would give a shot. That too though would be difficult to assure that you would have a male match.

 

[demjor19]

so...if you can go out and catch some wild Florida gar, and try to get an educated guess as to males and females, you could possible have a good cahnce of catching a pair?? Then, placing them into a few thousand gallon tank or aquarium together to breed. Only problem is getting them to actually do it, but to me this seems to simple without being done readily. I feel taking them out of their natural habitat would mess with their spawning cycles. If/when given the opportunity to do this, I think we would try it out and see what happens. Nothing is for sure to happen, but just like with our female black Rhom being one of few to have ever laid eggs in captivity, and it being unheard of for them to breed, nothing is impossible, and with the funds, even breeding them would be something I would give a shot. That too though would be difficult to assure that you would have a male match.

if you would ever be willing to try you know im up for it...although i'm sure it is more complicated than just simlpy getting a male/female pair.

 

[E_americanus]

ok there's been plenty said here that doesn't need any review, so i won't cover it all. but here are some bullet point responses as i don't have a ton of time right now:

- regarding gars in the wild, sexing, etc etc...it's possible to make a statistically sound guess given the right data. lit says this for the most part, and this is what richard and i are referring to.

- i'm not sure if i am misinterpreting what richard is saying, or if we're coming at this from a different angle, but from my earlier statement - i do in fact believe most Florida/spotted gars in captivity are stunted to an extent. not stunted to the point of keeping a big fish in a 30g tank all its life, but definitely stunted in the case that on average they won't grow as big as they do in the wild.

ALL the Florida gars i've seen in the wild (and i've seen a good amount) are bigger than the biggest Floridas i've kept, have seen others keep, and in many cases, those kept in public aquaria (although that last listed item comes closest).

there are too many issues with water quality, space, and metabolites and other things we can't reproduce in captivity that are in place in the wild which lead to larger specimens.

this is the case with most peoples' gars, mine included. my Cubans are around 4 years old, and they are about 16-17"...the broodstock they use in aquaculture and even specimens you see in some pics from the wild/aquaculture are much larger. same goes with tropical gars.

longnoses fall the same way, other than belle isle and some other large public aquaria tanks, i've never seen a captive longnose (home aquaria) that was anywhere close to what i've seen in the wild...given we're dealing with older fishes in the wild, but in some cases (like those in this thread, or the ones that were spawned in captivity by H. Azuma, these were smaller than what one often sees in the wild).

- regarding getting them to spawn: kara you are right in that there are some other triggers that we just don't quite have our fingers on yet (pardon the pun, i'm on medication ), and therefore just getting a bunch of gars and putting them in a big tank together doesn't guarantee spawning...some factors other than that may have to be in place. hopefully we'll eventually figure those out. the two spotted gars that TFH docments spawning were actually not in THAT big of a tank, meaning with the right conditions, a pond isn't needed (good news for all of us).

ok, i think that's it for now, but i think that responds to some of the topics mentioned thus far.--
--solomon

 

[Polypterus]

- i'm not sure if i am misinterpreting what richard is saying, or if we're coming at this from a different angle, but from my earlier statement - i do in fact believe most Florida/spotted gars in captivity are stunted to an extent. not stunted to the point of keeping a big fish in a 30g tank all its life, but definitely stunted in the case that on average they won't grow as big as they do in the wild.

ALL the Florida gars i've seen in the wild (and i've seen a good amount) are bigger than the biggest Floridas i've kept, have seen others keep, and in many cases, those kept in public aquaria (although that last listed item comes closest).

Different angle to the same thing...
It is clear that there is some definite amount of stunting in aquaria. This stunting however seems to actually be minimal in comparison to wild fish IMO.. (L. oculatus / platyrhincus here not L. osseus or Atractosteus)

By what very little data is available using larger sample sizes. Populations of L. platyrhincus average in the 15 to 16 inch range. (Hunt 1953) Of 611 gar (Collected February to June) in this study, the fish ranged from 10.5 inches to 24 inches. Average size was 15.8 inches. Methods in this study used material that would have excluded smaller fish but should not have excluded larger fish.

Now obviously there was either catch bias favoring fish in the 14 to 16 inch range or this is what tends to be more numerous and abundant for this location. Time of capture would have been during the spawning season so one could assume the majority of these fish where adults. (Maybe)

It was noted that the population in this study was very high density which also brings up the level of stunting in the wild as a result of limited habitat. (Sort of what Uland and I noticed in the abundant stinky pool populations of L. Platostomus in Southern Ill) Of coarse we have also both seen abundant populations of gars (L. platostomus, L.platyrhincus and L. osseus) that far exceeded the average size on a statistical basis. Garvana for instance which defies all natural laws or knowledge about these fish...

Just another thing we need to chat about sometime Sol..... Interesting stuff...

(Hunt. B.P, Food Relationships Between Florida Spotted Gar and Other Organisms in the Tamiami Canal, Dade County, Florida
Transactions of the American Fisheries Society
Volume 82, Issue 1 ( 1953) pp. 13–33 )