Reptile & Amphibian Forums

Is there anyone who has consistantly had fertile clutches of Eastern or Texas indigo clutches where most or all of the eggs are good and survive to hatching? Reveal the secret! I'm tired of starting with clutches with two or three infertile eggs and then watching two or three more eggs go bad. I'm thinking of mixing rodent diet with a heavy snake component from now until October. I'm guessing that in the wild adults eat more snakes than rats. Those robust Georgia indigos pictured here earlier this winter certainly didn't seem to be suffering from any parasites due to eating other snakes in the wild. Any thoughts?

Just kidding...if you've had any eggs you are ahead of me, but it seems like even the best get skunked from time to time. I hope I'm wrong and someone will "spill the beans".

I'll get 'em next year....

I know the feeling. For nearly 10 years I had a nearly 100% breeding success rate (and a 100% hatch rate)....this year....the big skunkaroo; quite a humbling experience but it sounds like others have had a difficult year as well. I feed quite a varied diet to my indigos that include: mice, rats, quail, chicks, SMALL rabbits, and fish. Rodent make up a large portion of their diet followed by quail and the other items are given sporadically for variety and perhaps important nutrients that we don't know fully yet. I believe the primary reason I didn't have success this year was due to a warm fall/winter and I couldn't get those nice cold fall days where I could just open up the windows to my snake room and let that fresh air in. A very busy traveling scheduling speaking at various herp symposiums didn't provide me the usual time I have in pairing up animals during peak activity periods; I probably missed some prime opportunities while out of town. That could have made a huge difference but I hope to get back on track this coming season. One nice thing is that I am not going to have to get a bunch of baby indigos started this year....better plan my vacation now!

Rob Carmichael, Curator
The Wildlife Discovery Center
Lake Forest, IL

>>Just kidding...if you've had any eggs you are ahead of me, but it seems like even the best get skunked from time to time. I hope I'm wrong and someone will "spill the beans".
>>
>>I'll get 'em next year....
-----
Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL

We really shouldn't suppose that indigos have a high hatch rate in the wild. As an apex predator, huge numbers of babies aren't really necessary. We may be trying to achieve something that isn't achieved in the wild anyway.

I do think that there are basic things as breeders that we can do to increase the likelyhood of healthy clutches. Some are "For Sure" others "Probably Help".

For sure: Don't breed every year, Don't breed too young, big cages for exercise, don't overfeed

Probably Help: Supplemental Calcium+D3, varied diet

I've had good years and bad years. This year... kinda' in the middle with indigos.

Doug T

While it's probable that indigo hatchling mortality is high in the wild I doubt the hatch rates are much under 100%. What possible advantage would be gained by laying infertile eggs?

There is no advantage to laying infertile eggs, however, I think what Doug was saying is that for those of us who do breed eastern indigos, know fully well the energy taxation that it takes to produce viable eggs. Indigo eggs are very unique compared to other snake eggs and the amount of calorie expenditure is probably very high and as such, if conditions aren't 100% optimal, and they never are, you are unlikely to get a 100% hatch rate. Of course, this is all just pure speculation as we don't have a lot of field data to use to back up these types of comments and most of our observations are in-situ.

Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL

>>While it's probable that indigo hatchling mortality is high in the wild I doubt the hatch rates are much under 100%. What possible advantage would be gained by laying infertile eggs?
-----
Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL

This is something that I have truly struggled with for YEARS.

Eastern Indigos becoming EXTINCT in the Wild due in part to habitat destruction and over collection for the pet trade.

Eastern Indgos with relatively LOW fertility levels and low hatch rates in captive breeding trials.

I have come to beleive that EASTERN INDGOS (D.c. couperi) have relatively low hatch rates and high infertility rates in the wild, which translates to same in captivity.

Theorized Factors that contribute toward high infertility rates in captive breeding trials:

Cage size: Larger cages-much larger, esp for adults. Cages that re 30-40% larger than anything we keep them in now.

Diet: A diet that is not so much balanced as completly varied, where no one thing constitutes the staple of the diet. Fish, frogs, Rodents, BIRDS, other snakes, salamanders, turtles. Captive bred Drymarchon are fed predominately MICE and RATS, the most convenient and easly obtainable food source.

Age: DOUG TAYLOR has it entirely right: People attempt to breed Couperi at a young age. Often the barometer of whether to try and pair them up is dictated by SIZE rather than age, which leds us to overfeed them to get them "To size" quicker. I beleive that TIME and not size is the greatest factor in sucessfull breeding of Couperi. I have said this in the past, but will say it again, IM MY OPINION Eastern Indigos should not be bred before they are four years of age.

In the end I beleive that we have a species that is not that prolific in the wild to begin with, and we maintain them in captive conditions which do not mimick the wild conditions they come from, and expect better results.

Bottem Line: You try to cater to their needs as best you can, but realize that just getting eggs is indeed a blessing from God.. and getting them to hatch is one also. And despite seemingly GREAT numbers racked up over the course of the years, I have been skunked on more than one occasion. I truly believe that it is a blessing producing them, and we dont always get blessed in the same area twice. Regardless of what we do.

Sincerely,

Fred Albury

Again I find it hard to believe that hatch rates in the wild are much below 100%. It makes no sense for the female to produce infertile eggs. I have heard from importers that they have never encountered a gravid wild caught female producing slugs.

I think it's much more likely that captive husbandry practices are the culprit. Do you think it's possible that like the rattlesnakes(a similar niche in the food chain here in the northeast) that they simply do not produce large clutches, produce every season, or at a young age(which you've already alluded to)?

Egg fertility may be 100% in the wild, but they might also only produce a few clutches in a lifetime. Stuffing them full of food and breeding them every year or even every other year may just be more than their bodies are programmed to do... and we get slugs for it.

I guess the good thing is we're thinking and discussing it. Somebody is gonna hit the nail on the head soon enough.

Doug T

>>Again I find it hard to believe that hatch rates in the wild are much below 100%. It makes no sense for the female to produce infertile eggs. I have heard from importers that they have never encountered a gravid wild caught female producing slugs.
>>
>>I think it's much more likely that captive husbandry practices are the culprit. Do you think it's possible that like the rattlesnakes(a similar niche in the food chain here in the northeast) that they simply do not produce large clutches, produce every season, or at a young age(which you've already alluded to)?

I also find it hard to believe that any species would naturally have poor fertility, it kind of goes against the concept of survival of the fittest.
I don't breed indigos but I work with another "difficult" captive breeder, Louisiana pinesnakes. I have had good success the past several years (thank God). One thing I have noticed is that at least in my colony, smaller males breed much better than larger males do- has anyone tried this approach with indigos? I realize these are two different species but they occupy similar niches with a somewhat similar life history (upland sandy pine inhabitant, large, fossorial, lays big eggs).

I also wonder, it is often said that indigos have a faster metabolism? How do we know? Has anyone taken an indigo into a lab and measured its metabolism to be sure this is accurate?

just some observations...
Dave B

When I say they have a faster metabolism, I just mean they process their food faster. Perhaps I'm using a term improperly, but it sounds better than "They produce poop faster".

Doug T

>>I also wonder, it is often said that indigos have a faster metabolism? How do we know? Has anyone taken an indigo into a lab and measured its metabolism to be sure this is accurate?
>>
>>just some observations...
>>Dave B

Starting from the top, I am of the mind that Eastern Indigos have rather low fertility/hatch rates in the WILD. This translates to failure to produce healthy neonates,even bi-annually, on a consistant basis.As a "community" of specialized reptile breeders we are constantly looking for the answer as to "why" some or even ALL of our captive reproduction attempts with Couperi meet with failure.

I reiterate,and have said in the past, that being able to consitantly reproduce Couperi is, in my humble opinion, a blessing from GOD. I have been blessed in this area for many years, only to suffer in other areas. And I have also been a bit damned in this area, if you will, only to find other areas of my life blossoming. (KIDS,HEALTH,FRIENDS)

So, I take the good with the bad, riding out the storms and hoping for clear skies. We all do. Its human nature.

I beleive that Doug Taylor hit the nail on the head when he said that often breeders push the snakes to breed every year, overfeed them like hell to get them to size to do so(Even though in my opinion size is not the major factor,AGE is.)And we confine them in cages which don't come close to mimicking the tracts of land that they move around in. They are confined.

Reminds me of the recent tragic events at the San Diego Zoo, with the death of two elephants, one of whom was only 36 years of age(Natural lifespan being 70 years of age) that died once transferred to another Zoo. This reveals a much more systemic problem with the handling, care and confinement of elephants at Zoos.

In the wild these awesome beasts live upwards of 70 years. In captivity, 92% of elephants forced to live as captives never reach their 40th birthday.

In the wild, they are able to walk betwen 30 to 50 miles during the course of a DAY, over a variety of terrains, with their families. In captivity? The A.Z.A.A. guidelines require as little as 1/40 of an acre of yard space PER ELEPHANT.

I think in this case that the isolation from family, lack of freedom of movement, and unnatural confinement contribute to the animals downfall and early mortality.

I'm going to sound P.E.T.A like, but in my opion they shouldn't be kept by Zoos at all. Nor circuses. 92% is too damn high a statistic. It represents total failure, at the cost of a intelligent creatures life. Perfect husbandry techniques for boas or crocs if you need to show success.

By comparison(How did I get on that rant anyway..geez?) Couperi seem to do quite well in captivity, I truly dont think that there is "SOME" secret to unlock the mysteries of why they dont procude fertile eggs or why the low hatch rate. I think that this occurs in nature, unlike the elephant debacle that you read above. So, you do what you can, hope for the best and realize that blessings come in MANY different forms, and Couperi eggs are merely ONE of them, not the ONLY one.

These are just my opinions, I hope I didnt ofend anyone and apologize if I have done so or rubbed exposed nerves raw.

Off the Soap Box for Now,

Fredrick A. Albury

Aztec Reptiles

P.S.
Congrats on your work with the Lousiana pinesnake. Thats awesome! Did your stock come from Ginters adults or did they come from K.J.'s?

Interesting... What do you think causes infertility in the wild? Is it a small gene pool,lack of mates or what? I know it sounds obvious but I can't think of any advantage of laying infertile eggs...

Also, I would still like to know if anyone has tried mating a smaller male to a mature female. Sounds backwards, but sometimes it works (referring to my previous post).

Thanks,
Dave B

Dave,

A)Smaller males can and often do end up as the next meal, albieght an expensive one.....

B) Often smaller males cant pin adult females, esp ones with good bodylength/weight. Often smaller males are also to young to breed. Which would lead to less fertility. On the flip side really large males seem to have their share of problems also.

C) Low fertility levels or hatch rates in the wild are NOT conducive to sucessfull procreation. I just think that the Easterns aren't that successfull in cranking out lots of healthy offspring, and that HEAVY predation on the ones that do get lucky enough to hatch is unavoidable. In short, they are an AXIS predator, as Doug mentioned earlier,...they dont NEED to produce large numbers and this would actually be counter- productive in the long run.

Now..send me some info on the L.A. Pines. Those are amazeing truly.

God Bless,

Fred Albury

On the note of males, I'm surprised nobody has mentioned single pair breeding as a possible source of low fertility in captive Indigos.

In just about every species studied, mating with multiple males has been shown to either lead to greater female fecundity and/or greater fertility. In other words, mating with multiple males means females lay more eggs, have a higher proportion of their eggs fertilized, or both.

Given the sexual dimorphism in Indigos it's seems likely that some male-male competion occurrs, so this possibility seems even more plausible.

Off the top of my head, I can think of peer-reviewed studies of birds, fish and insects that have demonstrated this phenomena. If I remember correctly, it has also been shown in mice.

I believe there is anecdotal documentation of this in captive snakes. Unfortunately it's all in the European hobbyist literature so it's not something we can order at our local college library. I have a friend who translates many of these articles, I'll see if he has any information.

There are many others here who are much more knowledgeable than myself on this subject since i've only been keeping indigos for 3 years & have not yet attempted to breed them.
However, i'll bet the use of multiple males would result in the death or serious injury of one or both of the males.

Eric
-----
If Jesus is your co-pilot, you'd better change seats!

Sorry, I should have been more clear. Not multiple males in the sense of having more than one in the cage, but multiple males in the sense of having a female copulate with multiple males within a breeding period.

Ah, OK. I should've read between the lines.
That may well have a positive effect. The only downside I can see is knowing the paternity. This may not be a problem with most species, but the couperi gene pool is rather small & IMHO this would only further confuse the situation.

Eric
-----
If Jesus is your co-pilot, you'd better change seats!

That is the obvious downfall if one is trying to maximize outbreeding and needs to know exact paternity.
-----
Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

1.2 Gonyosoma oxycephala - (Green)

7.5 Gonyosoma janseni - (Black)

0.1 Gonyosoma janseni - (Black & Tan)

Guys,

Easterns eat other snakes.

Including appropriately sized EASTERN INDIGOS.

I have known quite a few breeders that put their 1.1 Couperi together only to find that when they arrived home they had ONE really BIG FAT Couperi( Sometimes the female, sometimes the male)

The introduction of another male for combatting purposes sounds good, but in all the time I have bred and kept Eastern Indigos, which is quite a number of years, I have yet to find a keeper that is willing to risk the loss of one of his males for the sake of better results in the reproduction department. And that doesn't factor in the sheer amount of damage that they can do to each other in the process of combat. I imagine it would be reminiscent of the pic in Marzeks book(Python and Boa Reproduction) of the damage done to blackhead pythons during their male combat.

In short, I would think it a bad idea. Though I wouldnt rule out that it could make breeding results better. I have in the past,bred my female easterns with one male per breeding, and occasionally bred another male to the same female several days later. I like to keep detailed records of who the parents are and the lineage, so I avoid useing diffrent males with the same female at diffrent times simply for that reason.

Combat? The first thought that comes to mind: An expensive meal.

God Bless,

Fredrick Albury

It's for sperm from multiple males to be available for fertilization.

Again, sorry to not have been more clear in my post. I meant multiple males in the sense of allowing a female access to more than one male during a breeding season.
-----
Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

1.2 Gonyosoma oxycephala - (Green)

7.5 Gonyosoma janseni - (Black)

0.1 Gonyosoma janseni - (Black & Tan)

Wow, talk about confusion. lol

Ok...multiple male breeding: I would rather be able to ascertain exactly who the parents are, who the sire is, rather than have better breeding results. Gene pool is to small allready. It scares me that there may be people out there trying to reproduce their first clutches that AREN'T maintaining good records and TRYING to breed unrelated animals. But you only have so much control over what people do with
THEIR snakes. I pass on multiple males, I choose nice- clear record keeping instead.

God Bles,

Fredrick Albury

>>Wow, talk about confusion. lol

Sorry for the confusion. I did not specifically mention male-male pre-copulatory competition so I assumed it was obvious.

>>I pass on multiple males, I choose nice- clear record keeping instead.

Don't blame you there. Please note that I was not making a suggestion, but rather just offering an explanation as to why we might see less-than-expected fecundity/fertility in captive Indigos. If I were to work with Indigos again I would not use multiple males either.
-----
Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

1.2 Gonyosoma oxycephala - (Green)

7.5 Gonyosoma janseni - (Black)

0.1 Gonyosoma janseni - (Black & Tan)

If you wanted to breed with multiple males but wanted to be sure of the genetics then males with the same parents would be an option.

On separate occasions of course. I'm sure a snake would eat his brother alive in that situation, just like a human enlosed in an unnaturally small environment (trailer) would.

"Sibling males would work, wouldn't they?"

Perhaps not. There have been a few studies done where a female was allowed to mate three times with a single male or one time each with three unrelated males. In some studies the female who mated with the unrelated males had higher fecundity/fertility.

This is different from what you mentioned, obviously, but the results are still very interesting.
-----
Current snakes:

1.1 Gonyosoma oxycephala - (Silver/Yellow)

1.2 Gonyosoma oxycephala - (Green)

7.5 Gonyosoma janseni - (Black)

0.1 Gonyosoma janseni - (Black & Tan)

Or put the other way, what is it about multiple males that would be an advantage over a single male?

If it is sperm count or some other physical problem with a single male then I think siblings would work as well as unrelated males while keeping the lineage traceable.

If their is a genetic problem that causes low fertility with a given pairing then sibling males would not address that.

I guess we are way down the road on hypotheticals here. IF multiple males help, do they have to be unrelated (or not closely related)?

Answer the first definitively then study the second and we might get some clues.

Maybe we are pounding the wrong nail sometimes or pounding the same nail too often. Both right about a few things and maybe wrong about a few things. Consider... most clutches of eggs are doomed partially in the wild by the smallest of creatures in the indigoes world...bugs! probably up to half of all eggs laid are destroyed by insects or arthropods. Of what's left, the conditions (humidity, temp, etc.) aren't favorable. We try to control these factors as best we can. But what about the microscopic stuff? The collections can be as clean as we can make them but we will not really know a whole heck of a lot about them critters! And all the males of erebennus I have seen during mating season are the humungoids that absolutely demolish the smaller males. Remembering the feeding bites some of you have experienced calls to mind of what these intelligent creatures could do if they set their minds to it!! I'm sure some small males sneak in the back door when the big boys are busy sorting it all out, but that's when the low fertility could come into play. Never found a clutch of indie eggs and hope I never do but all others I've found had some eggs "sampled". Seen the big boys fight and it ain't pretty...someone usually dies...and I believe the smaller males would make a fair snack if they didn't dance right. Changing climate, small enclosures, pressure put on them by man are all factors. I think those pines would be doing just fine if we hadn't started destroying their habitat. No Phd here just some good old reading and fieldwork in Texas and just want to say these are my opinions only. Love this forum and love the knowledge gained. Hopefully I can join in with some real experience and get a pair of cribos to start then a pair of easterns! Thanks for letting me ramble. Let's see those hatchlings!!
Todd Hughes

Steve

Just because they look good in the wild doesnt mean they dont have parasites. When in captivity snakes are under stresses that we dont realize i.e. living in an unnatural enviroment. In the wild parasites are kept in check as there stress levels are normal. As soon as stress levels go up so do the parasite loads. For that reason I would either raise your own feeder snakes or clean the heel out of anything wild you might feed to your Dry's.
-----

Good points. Thinking back to when I bred kingsnakes and milk snakes, most clutches had none to few infertile eggs at the start. Most eggs hatched OK. But other than getting some hatchlings started, snakes were fed exclusively on rodents. Just as with my captive indigos they missed out on varied diet of other snales, lizards, etc.

It's hard to accept that indigos breeding in the wild would have evolved to waste so much energy in producing infertile eggs.

Does anyone know of other captive-bred reptile species which also show poor fertility such as indigos?

I've only bred one pair of unicolor for two years now, but their proportion of fertile to non-fertile eggs has been much higher than Eastern or Texas indigos. Same diet. Does this hold true for other unicolor breedings? Yellowtails? If breeding results are markedly different is this another indication that some of the snakes involved really are different species?

Will Boston repeat this year?