Sunday 8 August 2021

Three wasps and an aphid (or two).

I was chatting to my neighbour when he mentioned wasps on his Scot's Pine, and a Wooly Aphid. My interest aroused I asked if I could take some photos. I expected the wasps to be Dolichovespula sylvestris, the Tree Wasp, as that's the one we see in our garden. On approaching the pine I quickly realised these were something else as they had orange blobs at the top of the abdomen. It took me a lot of photographs, on this windy day, and a fair bit of research to manage to identify the wasps as Vespula rufa, and not Dolichovespula norwegicus, the other one with orange/brown abdominal markings. 

Vespula rufa.

My neighbour had thought the wasps might be predating the Pine Wooly Aphid which he had found in the tree, Pineus pini. The wasps were certainly searching through the foliage.

Pineus pini "wool" in the Scot's Pine, this aphid would be new for Orkney I think.

Going through the photos I was especially pleased with this one and then delighted when I realised that the wasp was in the process of eating the aphid, well that's what it looks like to my eye.

Vespula rufa with Pineus pini a nymph of Cinara pinea (Large Pine Aphid), also found in the tree.

A bit more investigation and I found a likely candidate for Vespula vulgaris as well, bit of a tricky ID.


Vespula vulgaris, very likely, awkward to ID with certainty, they are very variable.

Interestingly, despite them being fairly frequent a few yards away in our garden there were no Tree Wasps, Dolichovespula sylvestris in the pine.

However, when I got home, Louise who had been having a bit of a clean had caught one in the house.


Dolichovespula sylvestris.

Social wasps were first recorded in Orkney in the early 1980s I believe. In the last few years I have seen only Tree Wasp in the garden, this was a wasp fiesta. I'll need to go back and see if I can find the aphid not within a wasps jaws.

I did go back and found there were other aphids present. Pineus pini should only be about 1 - 2mm long and they don't run about in the foliage. The aphids I found were larger and through the excellent photos at Influential Points I reckon they are the Large Pine Aphid Cinara pinea.



Cinara pinea, a slightly damaged one and an earlier instar in the tree.

Aphid identifications now confirmed, thanks to Dr RD.


2 comments:

Imperfect and Tense said...

Interesting! I think we had a Norwegian Wasp on Hoy during the week, everything keyed out bar the the line on the face which I didn't manage to get a clear photo of.

Alastair said...

Not seen that one Graeme. Have just put a fruit, mollasses plate out, we'll see what that draws in.