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froggy
20th May 2010, 11:11
There seems to be very little information about the ecology of Pleurodeles nebulosus, so I thought that I would post this extract on the species from a paper that I stumbled on:

From: Scicilia et al. (2009). 'Contribution to the knowledge of Tunisian amphibians:
notes on distribution, habitat features and breeding phenology Herpetology Notes, volume 2: 107-132

"Pleurodeles nebulosus (Guichenot, 1850)
Pleurodeles is a salamandrid genus endemic to the Iberian Peninsula and north-western Africa. The systematics and general distribution of the species belonging to this genus were clarified by several recent researches (Carranza and Arnold, 2004; Carranza and Wade, 2004; Veith et al., 2004). The Algerian ribbed newt P. nebulosus is distributed across northern Tunisia and Algeria, except in the Edough Peninsula and surrounding lowland areas, where it is replaced by the endemic P. poireti (Carranza and Wade, 2004).

To date, the ecology of P. nebulosus is almost unknown. Pasmans et al. (2002) collected some field data on habitats and morphological characters of Tunisian Pleurodeles. They found most of the newts under stones and in clay piles, and assumed that temporary, shallow ditches and ponds in river plains were suitable breeding habitat for the species. Furthermore they observed that animals collected north of the Medjerda Mountain are smaller than those found south of the mountain range.

In the frame of the present study, all the observed reproductive sites (a total of 32) were wetlands with a temporary hydroperiod (swamps, marshes, ponds, floodedfields, pools and road ditches) with the exception of a single permanent pond. Larvae were found from the beginning of December (near Tabarka) to the first half of April (in the plain of Tunis). Adults and larvae were observed in water bodies with water temperatures ranging from 10 to 26.8 C, water electric conductivity values ranging from 221 to 2500 μS cm-1 and turbidity and macrophyte coverage values ranging from 1 to 3. The observed altitudinal distribution ranges from sea level up to 457 m a.s.l. (in the Medjerda Mountains). The highest altitude known for this species in Tunisia is 689 m a.s.l, near Fort des Chnes (8 km south of An Draham), where Pasmans et al. (2002) found a juvenile specimen. Six reproductive sites of P. nebulosus were found in Cap Bon Peninsula, where the species was not previously known to occur. Pleurodeles nebulosus is exclusively present in the temperate areas (average annual precipitation ranging from 400-450 mm in Cap Bon Peninsula and in the vicinity of Tunis, to 1500 mm on the Medjerda Mountain), with an average annual temperature of 17-18 C. The species’ southern distribution
limit in Tunisia seems to be the Medjerda valley."

It's not much, but there are some important environmental parameters that could be handy for keeping this species. Also, this confirms that these newts breed in largely temporary pools, so a dry season at the appropriate time of year may be beneficial for these animals.

Also, if any ecologists out there could clarify the how a measure of 'turbidity and macrophyte coverage' is determined, that would be great - what does a measure of 1-3 mean?

Chris

pollywog
20th May 2010, 11:41
Macrophyte coverage is the amount of plant matter covering the waters surface and normally taken as an estimated percentage.
Turbidity refers to the level of suspended particles in the water (how clear it is), perhaps to get a value of 1-3 they are compairing it to a suitability index of some sort? Does it not give further details in the complete article?

froggy
20th May 2010, 16:42
Yes, should have checked. Its not very specific, but:

"An arbitrary range value from 1 to 3 was established to characterize the water turbidity (1 = crystal clear water; 3 = extremely turbid water or argillotrophic system) and the macrophyte coverage (1 = total absence of vegetation; 3 = absence of open water)"

Azhael
20th May 2010, 16:52
Thanx for sharing this!
Information on this species is certainly very very scarce.
I see they have pretty much the same behaviour as the southern populations of P.waltl.