On a recent day out to the mountains to check out the dire snow situation in the local ski resort we were taken aback by just how many nests of processionary caterpillars we saw in the pine trees and how much destruction they had caused. There were vast areas of what looked like dead trees and more nests than I’ve ever seen. Some trees were groaning under old dried-out brown nests while others were still healthy-looking but covered in silky white “tents” about 15cm in diameter.
Processionary Caterpillars: Nests
What are these nests you might ask? For those not in the know you may even find them attractive, but take care and read on….They are made by pine processionary caterpillars (or chenille processionnaire in French), pesky little insects that can cause a nasty sting, and can be dangerous to babies, young children, anyone with allergies or a weakened immune system and pets. They are found attached to branches of pine trees throughout southern Europe and in recent years have been spreading further north. The Mediterranean area is particularly affected.
Each nest houses hundreds of processionary caterpillars all snuggled up inside. The little beasties keep warm in the sun during the day and sneak out at night to feed on pine needles. Their voracious appetites strip the tree of its needles which can eventually seriously damage the tree, even kill it. Certainly where we were near Gréolières les Neiges vast areas of forest looked dead or very sick. In the spring once the caterpillars have eaten their fill from their particular host tree they descend from the branches and travel reasonable distances across the ground to find a place to bury themselves and pupate.
Processionary Caterpillars: Processional Chains
It is while they are travelling across the ground in the spring that you can see where their name comes from. Processionary caterpillars are so-called because they travel in processional chains of up to several hundred head to tail all in a line. This of course looks fascinating and tempts people to take a look, touch, poke or otherwise get too close. People and curious dogs or cats. The problem with this is that the caterpillar is covered in microscopic urticating hairs which when touched leave a painful rash. In the case of dogs or cats, they will then lick the itch which transfers the hairs to their tongue exacerbating the situation and in extreme cases causing necrosis.
The hairs can also travel through the air resulting in respiratory problems. Anyone with allergies should take extra care around the nests and lines of caterpillars as the toxins can occasionally cause severe allergic reactions. Pet owners should take their animal to a vet immediately if they notice irritation around the mouth, nose and eyes or obviously if they actually see the animal touch the caterpillars.
The processionary caterpillar’s nests and chains are usually very obvious which makes it easy to see where you should and should not walk your dog or settle down for a picnic. There is no need to panic in areas affected, just be aware, take sensible precautions and don’t get too close.
I can count at least 24 nests in the above photo. Have you ever seen processionary caterpillar nests or the crazy processional chains? If so, where? I love hearing from you.
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Wildlife at Lou Messugo, what a bore!
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Hi trying to identify the processionary caterpillars we have spotted in our lane at Melrand France. Any chance you can help. We have photos . Thanks
I live in Alicante, Spain and was privileged to see this rare and possibly once in a lifetime sight-I’m talking about the processionary caterpillar. It was around Feb or March 2017. I saw a grandfather with his two young grandchildren looking down at something in the road and pointing to a nearby garden. I became inquisitive and as I got closer, I could make out what it was – a chain of backtoback brown caterpillars making their way across the road, luckily for them it was a culdesac so not many cars around ! I expressed my amazement to the grandfather and he said they come from the pine trees in that garden and pointed over. I didn’t know anything about them of course and fortunately I didn’t have a dog. I’ve been meaning to look this up ever since and am so glad I did as I now have fotos of them – thanks Phoebe !
I’m so sorry to hear about your dog David, these pests really are awful for pet owners. Interesting to hear your doctor’s theory about insecticides, though I can only think it’s a good thing to ban poisonous chemicals from our surroundings. Environmental and chemical-free options are often less efficient or demand a lot more hard work but overall a better thing for the future of us and the planet.
We have had our house in the south of Alentejo since 2006 and now live there permanently. For the first time this year we found nests in pine trees close to the house. I arranged ASAP to have the nests removed and burned but the caterpillars had started to descend from the nests.
It would seem that last Wednesday our little Yorkie just 2 years old had come in contact with one or more caterpillars and during the night he vomited. We waited one more day before taking him to the Vet who examined him but could not find anything wrong. She gave us her mobile number in case he got worse and by Sunday morning we were ringing her and taking him in. We left him with her but the next morning I was telephoned to be told that he had died at 2 am due to anaphylactic shock. In other words he was so poisoned his tongue had swollen so much he could not breath.
Today I was seeing our Doctor and we discussed this and he asked what I thought was the cause of the spread of these evil creatures. When I recited the usual global warming c**p he said no it was the EU which had banned a chemical agent that had been used for this problem and the EU norm was now to use a safer insecticide, which incidentally does not work. I am sure big Pharma are laughing all the way to the bank. If anyone knows anything more about this EU ban I would love to hear about it. Meanwhile keep well away from them and particularly try to make sure your dog does not go near them
I think different communes deal with them in their own way. I know around here many towns spray the pines though how efficient it is I’m not sure.
We have them in our area around Mont Ventoux. A friend’s tiny little puppy was just sent to the vet in critical condition after getting too close, and may loose part of its tongue. They need to be taken seriously. Has there been any attempt to get rid of them?
Usually their hairs can cause itching when in contact to human skin. So, might as well keep distant from them. But, I haven’t seen those that seem in procession. I was intrigued really. 😀
I believe they’re similar to the oak processionary but I don’t know much about them.
That’s awful that your school had this problem. I hope it got sorted quickly.
You probably haven’t had them in the exotic countries you’ve lived in EE.
A boring brown moth that lives for a day. Their glory is being a caterpillar!!!
It is amazing to watch, (from a safe distance), it’s just a pity they are so dangerous.
I don’t think many caterpillars can make you ill but these little nasties can so your mum was very wise!
They are fascinating, pity they are so nasty.
Always better to be cautious around unknown creatures!!
If you’re in UK you’ll be fine, they haven’t made it that far north yet.
You make me laugh Emma! Sorry but I’m having visions of you suffering in your tent trying to will a robotic bird to appear. Thanks for reading anyway, I appreciate your sacrifice!
Wow, that must be an amazing sight to see – do they turn into butterfly’s or moths
amazing. I did not know about them.
Oh wow they are incredible, I love how they travel in one great big line! SO amazing. Going to show this post to the kids when they get home as they love caterpillars x
Never seen or heard of them, but was always told as a child not to touch caterpillars as they can make you ill, used to think my mother was being silly, who knew they could cause so much harm, thank you for sharing
I used to see them a lot when I was younger and I never took the time to learn about it, so thanks for the post 🙂 I learned something new. We don’t have any pines here so it’s not a problem for us now, but I will tell my parents as they have loads of pines near their house!
I’ve never even heard of these before but they do sound fascinating – at least I know to steer clear if ever I see a procession of caterpillars now 😉
I have never heard about these before. I am not keen on butterflies, so these are not my favorite things!
Oh wow I have never heard of this breed of caterpillar before. I will need to keep an eye out when we take the dog on a walk through the woods at ours just in case
It took a lot for me to read this post, I have a MASSIVE caterpillar phobia! I have no idea why, but once nearly suffocated in a boiling hot tent with one of those huge fat ones (with a kind of pointy tail) on the outside of the door! 😀 We need to invent a robotic bird to come and eat them all, the real ones aren’t doing a good enough job!
Such an interesting post. I hadn’t heard of these caterpillars but know that the oak processionary caterpillar is a problem in my area.
I’ve not heard of these specific breed before but they sound similar to some we have in the UK. There was an infestation in the school hedge last summer and lots of kids were getting horrible rashes.
That’s lucky you could happily cut down that tree. Our garden is full of pines but luckily we’ve never had a nest.
Kids usually are intrigued as they are pretty amazing to see, just keep them well away Kriss, especially if they have allergies or asthma.
Very well named indeed, they are fascinating to see, it’s just a shame they’re so dangerous/harmful!
Yes they turn into dull brown moths that live for 2 days, completely harmless.
I haven’t heard of the ermine moth caterpillar but it sounds very destructive. I have however heard of the oak processionary caterpillar. I don’t know if it is as prevalent as the pine, I don’t know much about it.
I know of these but thankfully never seen them, although, as I said in response to Diane’s comment there are other species found further north – but not in Calvados where we live. We do occasionally get infestations of ermine moth caterpillars which build huge nests in plants such as hawthorn and can completely defoliate them but they are not common here. They are however a huge problem in the SE of England where I used to live. At least though, they do not affect humans or animals not being a hairy caterpillar.
Thank you so much for adding this precautionary post to #AnimalTales – the more people who know about the dangers, the more we can hopefully keep people and pets safe.
There are various species of processionary moth and it is possible, Diane, that you saw Oak Processionary moths which are more common further north – with some even found in Sweden. Their nasty effects are however the same which-ever species you come across.
Ooooo I’ve never heard of them but great to know. What a shame. Do they grow into moths? And are they still dangerous then? #AnimalTales
Oh, wow, I’d never heard of these before! They definitely deserve their name though, looking at that picture! x #animaltales
Yikes! I had no idea about these trailing creatures. Good to know about when we next visit southern Europe as I could just see my kids being absolutely fascinated by them.
Fortunately we only had one straggly pine in our garden when we bought the house here in the Charente Maritime. Sure enough it had a large nest in the top of it. We cut down the tree as it was ugly, and in a really silly position and then burnt the procession of caterpillars as we have two dogs. I remember the first time I saw them, maybe ten years ago, in the south of France, we thought they looked amazing until we were told what they were and our opinion changed quite rapidly!
I know they’re spreading north but I didn’t realise as far as Brittany. I’m amazed that the local housing commission/town council does nothing within a public housing complex, that’s awful. In my area there seems to be a bit more understanding, public awareness and pest control but probably not as much as dog owners would like.
They are 100% alive and well in the Maine et Loire where I live. I’ve had people read my post and email me from all over France so they don’t seem to be localized to one area. A neighbor told me he first saw them 20 years ago in Bretagne near the coast and over time as trees and other plants are transported, the dang caterpillars come with them so these days they’re commonplace. I haven’t personally seen any yet in town this year but that same neighbor saw about 5 huge chains outside the post office in town! SO SCARY. I want to put my dog in a protective bubble.
Last year when I saw nests and about 1000 caterpillars under a tree at the public housing complex we walk through, I told their management office and they just shrugged. I asked them to put up signs and no reply. Didn’t seem too concerned. My husband (who works for the town) emailed the pest control department from his work email and NO REPLY EITHER. I’m still miffed.
So do they exist where you are in the Loire area Diane or did you come across them on holiday somewhere else?
Completely useless IMHO. Hate these things with a passion!
This pests are horrible and until Dagny found them under a nearby tree last year, I had no idea they were anything but harmless. A French woman saw my pic on Instagram and warned me. Thank god nothing happened to us but I wrote a post about it as well to educate others and many of those who commented learned the hard way after their pup lost a part of its tongue. Thanks for educating people as well. I wish the towns would do more (even just put up signs if they don’t have the budget to exterminate). I always have an eye on the ground and in the trees when I’m out working. They’re out early this year! YUCK!
I don’t really see their purpose either other than I suppose birds probably eat them. Not being a pet owner I don’t need to worry too much and although we’ve got plenty of pines around here (the town is Roquefort les Pins after all!) I’ve only ever seen them once in 9 years in the area.
I’ve only ever seen the chain once, when I took these photos. They’re very rare at Lou Messugo.
They are fascinating to watch as the process along but not really a great idea to get too close!
a dull brown moth that only lives for a couple of days. 🙁
What kind of a moth or butterfly do they turn into?
I’ve seen the nests, but never their inhabitants. And now I don’t think I want to!
I have never seen these nasty creatures. Luckily I don’t think they would do very well in all our wind and rain. You keep away from them.
Horrible things. I hate killing anything, but if we had these in our garden, I would. They are so dangerous for pets. Luckily we don’t have any pine trees so we are not affected, but wherever there are, you can see plentiful nests. I don’t really get the purpose of these nasty beasts.