question about snakes on the roads

[lucy]

Many snakes are run over because they like basking on the hot asphalt.  I used to come across them when cycling, finding them stretched perilously on the roads.  They seemed to be in a heat-stupour, and would slowly pull themselves into the verge after much shooing.  Why is that?  Don't reptiles become more energetic the hotter they get?

[indalo]

Hi, Lucy

Reptiles, fishes, insects and other small beings are cold blooded. So they need, every day, get the temperature anywhere for their bodies. Of course, concrete and asfalt are good places for that; so as they are highly dangerous.

If you watch lizards in summer at very hot places, you can observe that they put their belly (specially pregnant females) on the sand or ground, for getting heat for the eggs. At the same time they put up the four legs for being not burnt... it is a very curious and common position in sandy places. This behaviour has been observed by myself in Acanthodactylus erythrurus at Cabo de Gata dunes.

If you want to learn more about the cold and worm-blodeed topic, here you have a fine link about it.

http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/

PD: Also temperature changes the colour of the outside of skin. You can observe this in our Tarentola mauritanica; when it is white is because it is cold, and when it comes black or blackish is because it is hot, and  then it is more active.

Regards, hope can help.

Jesús Contreras
Almería

[lucy]

Thanks alot for the answer, Jesús, and the link.  Maybe the snakes on the road had not been warming up long enough to be able to move quickly.

That's also interesting about the Tarentola mauritanica - I always thought the colour change was a response to light, rather than heat. 

[indalo]

About the influence of light in gekkos colour changes, really I don´t know. I´ll dprepare this question for you.

About snakes on the road, many times also they use the roads for getting a better digestion. So they come too heavy to move along the process, and are not able to go away in time when a car comes quickly upon them. It´s usual to find that crashed reptiles have many times other animals inside them.

A year ago aprox, I found a Malpolon monspessulanus with other animal of the same species inside it, that has been eaten by it. ¿Cannibalism?... possibly. Also it is the theory that they can eat on the road another animals that has been just crashed, and are yet fresh.

Sometimes also... they are crashed when heating the eggs on the road. A picture of myself about this, so as another about the supposed cannibalism can be watched at http://anfibios-reptiles-andalucia.org/especies/foto.php?imagen=bastarda&numero=1550.


Regards


Jesús Contreras
Almería

[indalo]

Thanks alot for the answer, Jesús, and the link.  Maybe the snakes on the road had not been warming up long enough to be able to move quickly.

That's also interesting about the Tarentola mauritanica - I always thought the colour change was a response to light, rather than heat.  

Sorry, I did not explain it appropriately. I have looked about this and indeed, texts talk about that light is involved int these colour changes. But in life and open environments, natural light is directly related with temperature (the sun)... isn´t it?.

More info will come about this.

Sorry

Jesús  


Learning every day.

[lucy]

That's an amazing set of photos - looking through them you get a great idea of how impressively massive the Montpellier can be! 

Thanks also for shedding more light on why snakes move slowly on roads - to their disadvantage, as the photos show.  But I like the idea of them looking for a hot surface to digest the food - it's like they are cooking it after swallowing, rather than before!

Looking forward to any info you find on T. mauritanica colour changes.

[indalo]

I asked my friend Juan Pablo of http://anfibios-reptiles-andalucia.org/imagenes/inicio.htm and herpetologist about this question.

JP answers you:

"Pueden cambiar de color las salamanquesas por motivo de luz, temperatura, estado anímico, etc., normalmente toman la coloración negra a primeras horas de la mañana y especialmente en invierno para recibir más el calor del sol. Tambien, aunque ni punto de comparación con el camaleón, pueden cambiar el color a más claro o más obscuro en función del substrato en el que se encuentren."

Kind regards

Jesús Contreras
Oz Nature Tours
Almería
Telf. 626260641
indalodeoz@indalodeoz.com
www.indalodeoz.com
http://www.youtube.com/watch?v=ze5MS_jHhJI
http://n2000.raar.es/cubic/ap/cubic.php/accion/Oferta_Ver/ofer/57.htm
http://www.spanishnature.com/almeria-province.html
http://www.yumping.com/rutas-4x4/oz-nature-tours--e19619950
http://www.unique-almeria.com/wildlife-guide.html
http://www.unique-almeria.com/famous-nature-photographers.html
http://www.unique-almeria.com/birds-of-spain.html

[lucy]

Thanks Jesús and Juan Pablo for all this information.