The Processionary Caterpillar is so called, because of their characteristic marching nose to tail in a procession.
According to information from locals and what we have read, the Pine Processionary Caterpillar (Thaumetopoea Pityocampa) is a nasty piece of work. The hairs on the caterpillar have tiny barbed hairs containing a protein called thaumetopoein, which is highly irritating to the skin. Contact with the hairs of the caterpillar can cause severe rashes and eye irritation.
Dogs are generally worst affected as they may be inquisitive and sniff them, or they may pick up the hairs on their paws, which they are prone to lick because of the irritation and hence spread the poison to their mouth.
Dogs may suffer breathing difficulties and vomiting as a result. Urgent veterinary treatment should be sought. Sometimes amputation of the nose or tongue may be required. If the throat is affected, suffocation and death may result.
As we have two dogs, we are obviously very concerned by this. We have seen hundreds, if not thousands of caterpillars, which look very similar (see photo above) to the Processionary Caterpillar. They are everywhere, in the olive groves and even in our courtyard. We have not seen them marching in processionary style, and there is a lack of pines here, but they look very similar. We have sent some photos off to experts for identification.
I shall update this post when I get a reply. In the meantime, we try to be very careful with our dogs, but it’s not easy!
Update 26 March 2018
Not a species I’m familiar with but the best match I can come up with is Rambur’s pellicle – Ocnogyna baeticum. There are several quite similar in this family.
I’m not aware of them being dangerous to dogs. Dogs and other potential predators normally leave hairy caterpillars alone due the distasteful hairs.
These are likely to be fully grown within two weeks and will then disperse to pupate.
Steve from Wildlife Insight
Reassuring to hear, but we’re playing safe, just in case and doing our best to keep our dogs away from them.