In terms of wildlife the Canary Islands are pretty safe. The endemic wildlife is limited to birds, bugs and dinosaurs, but nothing predatory. The most dangerous species is a poisonous centipede, which, theoretically, could be lethal to small children and the faint of heart, but otherwise there’s nothing really to worry about.
The dinosaurs are fairly tame, present in abundance (seriously! you have to look where you step, or you’ll step on them), and very willing to pose for a photo.