Yellow-bellied Slider

Not silly at all !! And yes that's right - it was in the Late eightys when there was a Run in the yellow bellied sliders as pets many of them where released, then in the ninetys the red eared sliders became even more popular - native to USA they rapidly became a threat for the native European tortoises as concurents !

Now this is probably a silly question but are they invasive or native to Spain? I kinda imagined some had been released as pets, but saw so many around Madrid that I began to question myself.

These are yellow bellied sliders except the very left One on Top of the other that's a Red eared slider ...