Oak Processionary

Thaumetopoea processionea

The Oak Processionary is a moth whose caterpillars are pests in oak forests and pose a health hazard because of their poisonous setae , which may cause skin irritation and asthma.
Oak Processionary imago, Heesch, Netherlands This photo is the result of Lisa and Christine putting in motion Moth Week. For the first time, it made me try out a little moth trapping exercise in the garden. An extremely simple setup: white blanket sheet on the wall, illuminated with a strong light. 

My expectations were low. Because the area we live in has many light sources, our garden being small and fully renewed this spring, and very likely I'm using the wrong light (I've read success rate dramatically increases with light of a specific wavelength that more closely resembles that of the sun). 

I had a spectacular start. First, I duck-taped the sheet to the wall, but it kept collapsing. Then I used screws to hold it in place. When trying to hang the light on one of the screws, I dropped it, and I cut my thumb on the shatters. Replacing the light bulb after the bleeding, it started to rain. We've had a record breaking drought for 2 months, yet at this very moment it started raining, endangering this open electricity that includes a very hot lamp.

Persisting some more, the rain was gone, and the second I turned on the light and turned of all other lights, immediately this one appears. The morning after, only now do I realize its the infamous Oak Processionary in its adult form. The caterpillar of this moth is considered a severe pest to people, and as soon as they are found, the tree is treated with a fluid poisonous only to this species. Furthermore, blue tit birds, which we have a lot of around the garden, deliver biological pest control.

Somehow this individual survived all that and made it to adulthood. I respect that. On the light:
https://www.jungledragon.com/image/63377/oak_processionary_imago_-_front_view_heesch_netherlands.html Europe,Heesch,Moth Week 2018,Moths,Netherlands,Oak Processionary,Thaumetopoea processionea


The wingspan of adult stage moths is between 25 and 35 mm. Their pattern of tan, brown and white make the adults difficult to see against oak bark. Adults fly during July and August. The larvae construct communal nests of white silk from which they crawl at night in single file, head to tail in large processions to feed on foliage in the crowns of trees, returning in the same manner.

Oak is its preferred food source, but it also attacks hazel, hornbeam, sweet chestnut, birch and beech.
Thaumetopoea processionea - Caterpillars  Caterpillar,Geotagged,Lepidoptera,Netherlands,Oak Processionary,Thaumetopoea,Thaumetopoea processionea,Thaumetopoeidae,nl: Eikenprocessierups


The moths are widely distributed in central and southern Europe, and are occasionally found as far north as Sweden. In the southern countries of Europe the populations are controlled by natural predators, but these predators do not exist in northern Europe. Their range is expanding northward, possibly or partly as a result of global warming.


Some text fragments are auto parsed from Wikipedia.

SpeciesT. processionea
Photographed in