David M

[David M]

Arctic Circle, 3rd to 10th July cont…

The second day was cooler and much more overcast than the previous one.

There were five of us so one (Jon) volunteered to go back up the cable car in the morning, which was en route to a site where the rest of us wanted to go to look for Lapland Fritillary.

The reason for this was that we had been searching unsuccessfully for Dusky Winged Fritillary, Boloria improba on Day 1, and I had subsequently been given precise GPS co-ordinates for Day 2, which showed we were 300m or so off track.

Sadly, there was no sign of Lapland Fritillary in the heavily overcast conditions at the site near Kiruna, but excitement came in the form of Jon texting me to say he’d found 3 Dusky Winged Fritillaries and that we should return if we wanted to see them for ourselves.

Obviously, we wasted no time but with 95% cloud cover and temperatures no more than 14c at the upper cable car station, I wasn’t confident.

I passed the point where we had been looking for it the previous day, not really believing that it could reside near the very top of the mountain at 1,300m in the Arctic.

That last 300m or so was a stiff climb, and conditions looked and felt quite austere upon arrival:

There were a few breaks in the cloud but it was quite windy, and I was feeling frustrated at having made such an error the previous day when the weather was much better.

Then, just as I felt things were hopeless, a small, blackish insect flew by me and landed about 20m away. As I approached, I recognised it as improba but it immediately flew into the air and was taken by the wind.

Cue an immediate redoubling of efforts and a little good fortune in the sense that the sunny intervals got a little more generous. Eventually, our prayers were answered and another shot by, coming down in the grass:

It wasn’t going to fly willingly in the wind and cool temperatures so I persuaded it to rest on a small bit of rock:

Quite how any delicate insect can live in such an environment is almost beyond comprehension.

This is why it is so difficult to find and is so coveted.

‘High altitude endemic Arctic butterfly’ just doesn’t sound right….but it does exist!

[millerd]

That is an amazing butterfly, David. I can see how it came by the name improba - it is completely improbable that any butterfly could survive living 1300m up an Arctic mountain. Imagine what the winter conditions are like - how do the caterpillars survive (I assume that like other fritillaries they overwinter as larvae)? Extraordinary!

Cheers,

Dave

[bugboy]

One presumes it takes a few years to complete its life cycle.

[selbypaul]

What an incredible species! Loving this write up of the Arctic, David. A really fascinating insight.

[trevor]

Must be high up on your butterfly of a life time list. An incredible find.
We learn something new every day!

[David M]

...I can see how it came by the name improba - it is completely improbable that any butterfly could survive living 1300m up an Arctic mountain. Imagine what the winter conditions are like - how do the caterpillars survive (I assume that like other fritillaries they overwinter as larvae)?

Indeed, Dave. An Arctic tundra butterfly, occuring nowhere else but in that habitat. Some sources say the larvae hibernate twice, but quite how they do so given the winter conditions up there is anyone's guess.

[Padfield]

Improbus, from my Latin dictionary (improba is the feminine, to go with Clossiana or Boloria):

Bad, inferior (in quality); wicked, perverse, cruel; unruly, persistent, rebellious.

I don't know which meaning the author had in mind, but perhaps 'unruly, persistent, rebellious' fits best!

Guy

[David M]

Arctic Circle, 3rd to 10th July cont…

The price to be paid for connecting with Dusky Winged Fritillary is that we completely forgot that the cable car shut at 1600h. This meant we had no option but to walk the 2 miles down the mountainside which was tough going in places. Sadly, it remained cloudy so there were precious few butterflies seen en route.

This wasn’t ideal preparation for travelling north to Alta the following day. When setting out, it was raining fairly heavily for the first hour but once we headed east into Sweden it cleared up and became extremely sunny and warm.

We stopped briefly at a Sami café for a snack where I was taken by the three Nordic flags flying side by side:

We then had to traverse that little strip of Finland that lies between Sweden and the far north of Norway and we duly made sure we did a roadside stop just because none of us had ever set foot in Finland before. Few butterflies were seen, just the odd Idas & Cranberry Blue and a few Pale Arctic Clouded Yellows.

Upon re-entering Norway, we stopped at a lowland bog to look for Lapland Fritillary, Euphydryas iduna, which was probably #2 on our target list of species.

I don’t much like looking for Large Heath in the UK in habitat such as this, and the strong sunshine and 22c temperatures had evidently sent the flies into overdrive, so I was mightily grateful to Jon who managed to find a solitary individual when it looked like we would miss out:

Although from the above angle, the butterfly looked in decent condition, when it fully opened its wings it had a fair amount of damage on the right hindwing:

Unlike Cynthia’s Fritillary, both sexes in iduna have the white upperside ground colour. I’m sure when fresh this butterfly must be absolutely stunning.

There were several other species around, most notably Frigga’s Fritillary, Boloria frigga:

Seeing these was just the boost needed after such a long drive following on from the exertions of the previous day.

[David M]

...A useful hint for any future Frejya's frit (a butterfly I only know from the books) you find stuck in the mud: the iPhone light is perfect illumination for cameras to focus on. I use it a lot in pitch darkness for caterpillars and also in dim light for moths, coupled with flash for the actual picture.

I really wish I'd had the good sense to use my mobile phone camera under the circumstances, Guy.

Too late now but I'll be better prepared for any future, similar event!

Must be high up on your butterfly of a life time list. An incredible find.
We learn something new every day!

Certainly right up there, Trevor (although Lapland Fritillary the following day was just as satisfying).