Newt belly pattern recording

[caleb]

Hi all.

With the discussion on the legality of owning captive bred individuals of protected species, I was wondering if anyone was keeping records on
individual newts, and particularly recording by belly pattern.

Belly patterns have been used to identify individuals of crested newts (T. cristatus group) in field studies in the past. One method used animals in a plastic bag on a photocopier, another used an angled mirror to allow photography from below.

I recently bought a scanner for my computer, and am interested in using it to record and quantify colour change in the belly patterns of Bombina toads under different feeding regimes.

I've built a small perspex box (glued with epoxy resin) to protect the scanner, and allow the animals some moisture. A piece of foam rubber the
same size as the box allows the animal to be pressed down gently to keep it in the same place during the scan.

It seems to work quite well for the Bombina, though I'm not sure it would be as good for less robust or placid species. I suspect it would be a good way of keeping track of individuals of any newt with distinctive belly markings.

Any comments?

 

[kai]

Hi Caleb,

You can also use a wettened towel to gently keep the newts from moving. A plastic box helps to reduce heat stress since the glass plate of a scanner gets hot pretty fast (especially with several passes needed for color scans). If you needed to make long scanning sessions one could try to pre-cool the scanner with a plastic bag filled with ice cubes and water (haven't tried this yet).

You'll need to scan many newts repeatedly since the pattern tends to change/develop from juveniles to adults - and even changes with some adults (e.g. Paramesotriton).

Best wishes,
kai

 

[caleb]

Thanks for the advice- I've never had any trouble with the scanner heat yet, but I'll bear it in mind.

My scanner can do colour in single pass- I try to reduce stress by doing a low resolution pass (quicker than a high-res one) without a preview.

 

[kai]

Yup, that sounds good.

 

[fiona]

won't the brightness of the light be disturbing or blinding to them?

 

[caleb]

It might stress them for a short period of time, but it's had no long term effects on the Bombina toads I've used it on.

I don't think it would be any worse than taking a couple of photos using a flash...

 

[kai]

Also the eyes of most caudates are situated a little bit dorsally; covering the individuals with a damp cloth will help to limit direct exposure of the eyes. I agree with Caleb that this doesn't pose more than a temporary inconvenience. From my experience this seems to be true for specimens well used to captivity - I'm not sure I'd want to try this with freshly WC individuals of those species which shed their tails when stressed though...

Best wishes,
kai