by Gabriel Martínez » Thu Oct 17, 2013 11:34 pm
Hi all!
Jurgen, you can not compare EEUU with Western Paleartic. Jeroen is right! I don´t know why but in Morocco, in the BEST night, we have found 4 snakes in road. In Israel, maybe best night you find 15 snakes in one night. In Oman, best night 14 snakes (after some night snakeless). But in Arizona, I have heard stories about 80 snakes in 1 night!!! This is impossible in the the mediaterranean or Arabia.
Some people say that in Europe, our cultures (Islam, Judish, Christians) make us to hate snakes so we have been killed snakes probably during thousands of years, whereas in EEUU, local people respected snakes (animals were divine creatures) so they didn´t kill them, and snakes have been died only 500 years ago and the densities continue higher than in the "old world". True? False?
Also in EEUU desert, there is a monsoon during summer and snakes are highly actived even in summer. In Spain, Croatia, Morocco, Oman (except tropical areas) or Israel, animals in desert/mediterranean areas less of 1200masl are usually hidden and poorly actived during summer and there is only 2 moments of high activity, spring and autumn. Maybe a higher activity through the year is related with more reproduction moments and more hatchlings and higher densities. True? false?
We was talking in the forum before about snake activity. In Morocco, in very good places for Cerastes, you try in a good night and you don´t find nothing. In Oman also you can check the dunes in a good night and you don´t find nothing (lot of geckos, mammals and invertebrates and 0 snakes). The only exception that I know is the Israel Western Dunes where from april-october always is possible to find Cerastes actived (usually more than 15). There is no important the moon, the wind, etc... and there is no important studies of this in the Western Paleartic but some nights are good and other are bad. Even some years are good and other are bad. In Morocco, some aissaoui say that years with lot of rains are bad for snakes. I don´t know if this is true, but really some trips you find many herps in roads, and other year in same days you don´t find nothing! And is seems a similar weather and conditions, something change? what?
In general, we have to admit that density of snakes in EEUU is higher than Israel, Oman or Morocco. And in Israel, densities are higher than Morocco. Stanner & Mendelssohn made some interesting works about VAranus densities and they told that Varanus populations are higher in Israel than in Sahara desert (a big difference, maybe the double of individuals for each kilometer) and probably this happen also in snakes. Maybe because weather, predators, food, human impact and other factors...
This is very interesting, don´t know why nobody have studied about this in WP...