Thanks for the info.Also just been told about RODENTOZUL which we bought off the shelve
in mercadona for 3.70 euros so we have just started to use this.Same sort of system plastic
bags you put in the trees.
 

Rats are rats....if you want them gone you have to feed them something bad for them! Mostly rats show up when there is some form of natural food available e.g. almonds, figs, dates etc and you tend to see them as the family expands. As this is about now I tend to give them Ratiprom 2 which is available from local hardware stores. It is a red paste in a paper sachet which is very effective.
It is supposed to be safe as far as domestic pets are concerned but I still try to locate the bait out of reach, either at the entrance to their nest holes or in the palm tree where earlier fronds have been cut. If you can leave them slightly visible you will see when the bait has been taken. Re-bait as there are usually more rats than you think! This usually works very quickly but nature being what it is you will never completely cure the problem as a new family will move in eventually.