A couple of days in Oslo

Summer holidays are not yet over but we are back in Oslo for a couple of days before heading off again. I used the good weather to continue my hairstreak quest so if you were hoping for birds I am sorry to disappoint.

My search for hairstreaks in my local neighbourhood began last summer and was prompted by a lack of previous records but a good number of suitable trees (oak and elm) and I discovered good numbers of purple hairstreaks (eikestjertvinge) and had a couple of white-letter (almestjertvinge). I also experienced how difficult it is to find these species with no sightings of nectaring individuals and just sightings high up in trees with numbers differing significantly between visits.

I have already had one sighting of white-letter this year on 17 July but subsequent visits to the same tree and others in the area have drawn a blank. Yesterday I visited the same area in perfect conditions and sat staring at oaks and elms for a long time without joy but suddenly a brown butterfly darted over the grass and eventually landed – a male brown hairstreak (slåpetornstjertvinge). I have previously had a female in the garden and this sighting strongly suggests there is a population in the area that are presumably laying on plum trees. This sighting is also the first to be reported in Norway this year.

Today I had no hairstreak in that area but not too far away I found 2 white-letter and a purple so can consider my searches to be a success! The first white-letter came when I had stopped to scan an elm and noticed a small brown butterfly flying over the grass by my feet. It stopped on a white clover and revealed itself to be a slightly worn white-letter. I got to see it well and the result was my best pictures so far of the species (which seems to happen with every encounter I have). It disappeared as quickly as it appeared and I returned to scanning the elm and was quickly rewarded with another, and much fresher, individual. It showed quite well for a few minutes before disappearing into the tree and I never saw it or another one again despite many, many minutes of scanning. I also spent a loooong time scanning the oaks in the area and was eventually rewarded with a single purple hairstreak. It may still be a few days too early for this species but after last years experiences I had expected to find many of them and easily so I am a bit worried that it is a bad year for them.

 

Apart from the hairstreaks there are VERY few butterflies at the moment (which is being commented on a lot on social media) and other than the hairstreaks I only had a few whites (of all three species) plus a single small copper.

male brown hairstreak (slåpetornstjertvinge) - males have brown upperwings whereas females have an orange patch

males have also less colourful underwings and perhaps slightly shorter "hairs"

although they do show their upperwings occasioanaly whilst nectaring it is ofte only in flight that you get to see the upperwing

white-letter hairstreak (almestjertvinge) never seems to rest with its wings open

 and they are also significantly smaller than their brown cousins

this individual has slightly worn wings and short "hairs" and I would bet is a male

a flight shot showing the upperwing is just brown as can also be seen in the video of it taking off (in slow motion)

the second white-letter. This is a much fresher individual with longer "tails" and was hanging out low down in the tree and I would bet is a female

the wings were held slightly open showing far more orange at the wing tip than in the other individual

various shots of the first one

the purple hairstreak (eikestjertvinge) I saw was not exactly photogenic

small copper (ildgullvinge)