Whilst walking in the Cumbres Verdes I followed a track into a pine forest and came across many lines of Pine Processionary Caterpillars.
These harmless looking caterpillars (which turn into moths) can be very dangerous to pets (mainly dogs as they are inquisitive) and some humans. When disturbed they shed their fine hairs which irritate our skin causing very itchy rashes, if the hairs get into the eye, nose or throat area, then im sure you can work out the trouble you may get into. Even just sitting under a tree with the nests in can cause you to get a rash. Children have been known to go temporarily blind from rubbing their eyes after picking them up and many dogs have lost their lives or part of their tongue!
They are a big problem in Spain and are devastating forests because they make many nests in one tree and eventually kill it. This photo shows the devastation in one tree.
