T.gigas litter sizes in literature

[Jordi]

Dear all,

I couldn't find the answer through the search function, so here it is, not sure if this is the right place for this question though. Currently i'm working on a scientific paper which requires me to find litter sizes of Tiliqua species, and in specific for T.gigas (irregardless of which subspecies). So far I'm having trouble finding references that describe litter sizes for this species. I found a paper by Groseman which mentiones two litters (4-6 young), but that is about it. Several internet sites state however that litter sizes may reach up to 15 young, not specified for which Tiliqua spp., but I haven't been able to verify that through literature. So I was wondering if you could help me out here.

Do you know any articles/book chapters etc. that has detailed information on the litter sizes of this species? Preferable a study that actually observed the litter sizes.
On the other side, what are your personal experiences with litter sizes for this species?

Kind regards,

Jordi

[Dakota]

In my limited experience, my litter sizes ranged from 2 to 7 between two litters, both were Tiliqua gigas evanescens. It seems 6-8 is pretty typical, but this is just what I've observed. Hopefully Susann will chime in with her litter sizes — she has a bigger sample size.

In my experience, the babies are born quite large, too — ~20 cm at birth. It seems Meraukes have the biggest babies of the T. gigas complex, but this is also just my observation.

Here is a post posted by Jos of his litter sizes in 2013. He seems to breed Meraukes quite consistently in the EU; may be wise to get into contact with him.
viewtopic.php?f=4&t=24047#p437647

[Bluish]

Based on my 5 female T.g.e. that have produced babies i think they produce 12 ova/babies if they are well conditioned. Whether that results in 12 babies is another matter.

[alichamp]

Haven't read it myself but the book Blue-Tongued Skinks: Contributions to Tiliqua and Cyclodomorphus is considered 'the text'. Might be worth checking that out if you haven't already to see if it has the detailed information you are after.

[Jordi]

Thanks everyone. Ok, so 6-8 seems to be the average. I've definitely heard about the book, but I don't have it myself. From what I could find, this book describes litter sizes up to 15 for T.gigas. Unfortunately, I'm stuck in a field office in Asia at the moment, so I cannot order the book in time. Would someone be willing to scan that page for me? With of course a mention in the acknowledgements of the to be published paper.

[Dakota]

Here you go. This is located on page 192, "Husbandry and reproduction of Tiliqua gigas (Schneider, 1801) in the terrarium".

KIMG0008.JPG

This is the information on the contributor of this chapter:

KIMG0010.JPG

In this chapter, it does not differentiate between the subspecies. However, there is a chapter before this one discerning the natural history and organismal ecology of the species complex by each subspecies. It mentions follical development from wild collected specimens. Interested in this, too?

I think you should be mindful of the fact this species is rarely consecutively bred in captivity, though the last few years a few people have got it down to a science (Cough, cough, Susann and Bluish). 6-8 is just my observation, not a scientically based opinion. The sample size is quite small overall, still. I think you will have some further insight talking with importers of this species, since it is common for females to come in gravid.

Also, Frank B. Yuwono is the photographer responsible for most of the wild Tiliqua gigas photographs in the book. He informed me that Dr. Glenn Shea never actually stepped foot in Indonesia or Papua New Guinea to study Tiliqua gigas, which I found interesting. Frank is very knowledgeable when it comes to the species, and can differentiate specific locales from the varying scalation patterns and plates they exhibit. It is actually quite amazing talking to him if you have an interest for the species, though he says he is a bit "rusty". I can probably get you into contact with him if you want.

[Jordi]

Thank you so much. This will help me a lot. If you could get me a screenshot of the follicle development that would be even more awesome, thank you so much.
Ah, that is indeed interesting, you say that Frank Yuwono can ID localities from the patterns? I've got photos from a couple dozen blue tongued skinks taken in Indonesia last week, do you think he would be able to help?

[Dakota]

Yes, here you go:
Tiliqua gigas keyensis

KIMG0020.JPG

Tiliqua gigas evanescens

KIMG0017.JPG

Tiliqua gigas gigas (may have to click attachment and zoom)

KIMG0012.JPG

The chapter starts on 177, "The New Guinea bluetongue, Tiliqua gigas (Schneider, 1801): Ecology and review of the subspecies, with the description of the subspecies Tiliqua gigas evanesces Shea, 2000". I believe there was a bit of a typo in the title.

Please send me a PM, and I'll be happy to guide you to him. When we spoke, he seemed to rely more on scale plates than pattern, but I cannot speak for him. He took into account all of the scales, rather than just relying on the temporals for example.

[Jordi]

Thank you! This helps a lot. I will sent you a PM.

[Susann]

Hi Jordi.

Fantastic work you're doing!

I have produced litters from three different females over 5 years now; the first 3 years each female averaged around 6-8 fully formed fetuses along with a few "slugs". Then, last year, one female had a litter of 13 fully formed babies, another had 15. Here you can see more info and "proof" on that litter.

Feel free to PM me for more info.