Thursday 11th July 2013

I take it all back – well, almost!

Following my disparaging remarks about butterfly-watching in Scotland, and about the climate, I find myself having to eat my words! On the way home from the ferry terminal in Newcastle, I stopped at a boggy reserve near Dumfries, which I knew held another species which I would have looked for at its (almost) only site in the Netherlands, but did not manage to squeeze in a visit.

Arriving at the reserve car park in temperatures approaching 30 degrees and blazing sun, I was first pleased to start my 2013 Scottish butterfly list with numerous Ringlets, Aphantopus hyperanthus, and two Large Skippers, Ochlodes venatus, the latter of which only occurs in the south-west of the country, and which I missed last year.

I then ventured through some pinewoods, and came out into what looked like a snowfield! The cotton grass was turning the entire place white, an extraordinary sight.

The cotton grass looked like snow

This area was formerly used for small-scale peat extraction, but is now a well-protected reserve, although removal of young birch and pine saplings is a constant struggle. I met a man who told me that he used to walk and play here as a child during the War, and he could remember the peat cutting going on, all done by hand. Luckily this magical place has escaped the fate of a similar bog at Eastriggs, near Gretna, which is in the process of being completely decimated by peat extraction for the garden industry. The moral of the tale is, FOR PEAT’S SAKE DON’T BUY PEAT!!!!

At first there seemed to be nothing moving, and the heat shimmer above the bog made scanning with binoculars almost useless. However, eventually a medium-sized, rather drab-looking brownish butterfly fluttered by – my target species the Large Heath, Coenonympha tullia. This species has suffered heavily across Europe in the face of the destruction of peat bogs, and many of those bogs that do survive are no longer suitable as they have become too dry. Here, the drainage channels have been blocked, allowing the water level to rise again, which in turn provides ideal conditions for the Large Heath’s larval foodplant, cotton grass.

A channel reblocked to allow the water table to rise

Large Heaths are notoriously difficult to photograph. They fly for extended periods above the extremely rough and boggy terrain, and then land, usually in an inaccessible spot. By the time one has plunged through the tussocks, they have flown on again. I tried to photograph them with my Panasonic Lumix camera, but the autofocus focussed on the surrounding grass stems. I managed to obtain a few passable record shots with the 300mm lens on my Nikon D70s, but they are nothing to be proud of.

A distant Large Heath nectaring on Cross-leaved Heath flowers

There is a Large Heath in there somewhere!

By the time I finally retreated from the sun (such a rare experience in Scotland, and then I complain about it!), I had seen at least 25 Large Heaths, showing that on this site at least, the species seems to be thriving. But for its sake and the sake of other bog inhabitants, DON’T BUY PEAT!!!

2013 Butterfly list as of 12th July: 66 species

2013 Scottish list: 3 species

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Wednesday 10th July 2013

Good news all round – well, almost!

Yesterday, Tuesday 9th July, I spent the afternoon in the beautiful Hoge Veluwe national park, in the centre of the Netherlands. This wonderful area of heathland, pine and deciduous forest is one of the last bastions of some Dutch butterflies, one of which I was particularly on the lookout for, the Alcon Blue, Maculinea alcon.

This butterfly, with its incredible relationship with ants and its requirement of the rare Marsh Gentian, Gentiana pneumonanthe, is extremely restricted in its localities, and individual colonies can number as few as ten individuals in a given year. In past years, I have observed this species, in a tiny patch of damp grass with a few Marsh Gentian plants (which are difficult to see now as they are not yet flowering) and Cross-leaved Heath, which the adults use as a nectar source. However, this time, there was not a sign of this enigmatic butterfly. Perhaps I was too early, and they have not yet emerged, or perhaps this tiny colony has succumbed – I did not manage to find any here last year either.

The (former?) habitat of the Alcon Blue

Not all was gloom, however. Not only did I see at least 20 Heath Fritillaries, Mellicta athalia, even in areas of the park where I had not seen them before, but I also saw at the very least 30 Dark Green Fritillaries, Argynnis aglaja. One of the factors holding butterflies back in this dry heathland is the lack of nectar-bearing flowers. In recent years, at least two patches of mixed wild flowers have been sown specifically for butterflies, protected with an electric fence against the predations of Wild Boar. The mix included the wonderful Corn Cockle, once common in cornfields, but now virtually extirpated in the wild. The patch in the southern part of the park was alive with Dark Green Fritillaries, whereas the other, further north, attracted several Heath Fritillaries. If only more such patches could be planted!

A patch of wildflowers sown specifically for butterflies

Other butterflies I saw were two fresh-looking Green Hairstreaks, Callophrys rubi, a perhaps surprisingly late record as this is a truly spring-flying species, but I have frequently observed them in July in this park. Numerous Large Skippers, Ochlodes venatus, and at least a few Small Skippers, Thymelicus sylvestris, were in evidence, as well as several Small Heaths, Coenonympha pamphilus.

A late Green Hairstreak

A Heath Fritillary that landed on my bike!

Today, Wednesday 10th July, turned out to be one of the highlights of my butterfly year so far. I was due to leave Ijmuiden on the ferry to Newcastle (I am writing this post on board), and I had ideas of visiting some butterfly areas on my way to the port. However, the day dawned cold and damp, with a strong wind and some slight drizzle. I decided to turn my attention to birds, and managed to see a Marsh Sandpiper, Tringa stagnatilis, close to Amsterdam, which was a new species for the Netherlands for me.

Despite the cold, I was surprised to see several Red Admirals, Vanessa atalanta, and a couple of Small Tortoiseshells, Aglais urticae. Spurred on by these sightings, I decided I would return to my original plan, just in case a clearance might occur – and it did, with some slight gleams of sun just as I arrived at my first butterfly destination, close to Castricum, in the dunes that run parallel with the North Sea along much of the Dutch coast. These dunes, mostly covered with woodland and scrub, form one of the great butterfly areas in the Netherlands, and the sheltered valleys with their swathes of wild flowers host strong populations of several species that are hard, if not impossible, to see elsewhere.

My first target was the Niobe Fritillary, Argynnis niobe. I had only occasionally observed this species in the Netherlands before, once indeed in the Veluwe, where it is now extinct. As I approached the area where they had been reported, the weather looked far from promising, but almost immediately I left the track, a Niobe flew up from just in front of me, and I then went on to find at the very least 30 individuals, some looking quite fresh, and others not, including one that was so faded that it appeared almost white. They were sheltering among some low brambles, but when disturbed, they flew off vigorously, and were hard to approach when they settled again, making photography difficult.

A Niobe Fritillary – why is there a grass stem whenever one does not want one?

A Niobe showing its distinctive underside – this time with 2 grass stems across the image!

Why the Niobe has disappeared from its former strongholds in the centre of the country is a mystery. As few as 15 years ago, it outnumbered the Dark Green Fritillary, which still survives in reasonable numbers. Perhaps the lack of flowering plants affected it. One particular part of the park used to harbour large numbers of Ragwort plants, which attracted numerous fritillaries, but I observed park officials removing these plants en masse by the roots a few years ago. When I protested, they informed me that if this were not done, large animals would be poisoned. Perhaps the Niobe that I photographed here in 2006 was one of the very last individuals of this population. Luckily, in the dunes they seem to be doing relatively well.

The Niobe I photographed in 2006 – was this the last individual to grace the Veluwe?

Flushed with this success, but slightly conscious of the clock ticking towards the time when I needed to check in for the ferry, I decided to head north to hunt for another butterfly for which the dunes forms one of its last Dutch bulwarks, the Ilex Hairstreak, Satyrium ilicis. Contrary to what its name might suggest (Ilex is the Latin name of Holly), this species requires low-growing oaks. I had hoped to see it in France and Belgium last weekend, but did not succeed.

Having passed through some much taller oakwoods, I came out into an area of low oaks, and almost immediately I spotted a small, dark shape fluttering round a young tree, and it proved indeed to be a fresh-looking Ilex Hairstreak. I went on to see at least six, two of which were highly cooperative and allowed me to photograph them at extremely close range.

The Ilex Hairstreak, which posed so cooperatively

On my way back to the car, I spotted a small, gingery-coloured butterfly low in the grass, and as soon as it landed, I needed to carefully approach it from the front, always difficult as they normally see one and fly off. Luckily this one did not, and sure enough, I was able to clearly observe the jet black underside of the tips of its antennae, clinching this butterfly’s identity as another new species for my 2013 list, the Essex Skipper, Thymelicus lineola. Virtually the only reliable way of separating Essex from Small Skippers is by examining this feature, the Small Skipper’s antennae being orangey-red.

The Essex Skipper, showing the black tips to its antennae

By now the time was really running short, but I felt I had to check a locality only a few yards off my route to Ijmuiden, specifically for yet another potential new species, the Queen of Spain Fritillary, Issoria lathonia. This species is also most easily found in the dunes, and it only took me perhaps ten minutes of searching to find one individual, which sadly did not allow me to photograph it. This was a pity as it is a supremely beautiful species, particularly the underside, which bears almost unbelievable silver spots (hence its name). I did manage to photograph a bright Emperor Dragonfly, Anax imperator, which landed in the grass for a few seconds.

Emperor Dragonfly

I then had to make my way rapidly to the ferry port – and now I am engaged in what could be described as a butterfly-lover’s suicide: returning to Scotland at the height of the butterfly season. Other than Iceland, one could hardly choose anywhere with a more impoverished butterfly fauna than Scotland, situated as it is far from the continental landmass, and suffering from a butterfly-unfriendly climate. I will be hard pushed to find 15 species in total during the coming five weeks, but I shall try to make the best of it. What it does mean is that I shall miss some key species in the Netherlands, Belgium and northern France, which will have finished their flight period by the time I return towards the end of August. Still, c’est la vie, I suppose – and who knows what surprises I may find?

Butterfly list as of 10th July 2013: 65 species

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Tuesday 9th July 2013

Scorching temperatures, but few butterflies

This weekend saw dramatically increased temperatures compared with those of recent weeks, and I was out in my favourite areas in northern France and southern Belgium, full of hopes of finding large numbers of high summer butterflies, but still there were far fewer in evidence than I would have expected. Perhaps they are still to emerge, but it seems that the cold spring has knocked many species back quite severely.

Saturday 6th July saw temperatures of around 30 degrees Centigrade, and a thundery feeling in the air. Such conditions often cause butterflies to be reluctant to fly, and a long walk through my favourite forest produced very little, other than four Silver-washed Fritillaries, Argynnis paphia. These magnificent insects, with their bright gingery uppersides and beautiful sailing flight, are truly the kings of the summer forests.

A male Silver-washed Fritillary, easily recognised by the dark streaks along the veins on the forewing

The following day, Sunday 7th July, I headed eastwards into Belgium in the hope of more sightings. Whilst still in the car, two large purplish butterflies shot past, showing a slight yellowish tinge. These were almost certainly Lesser Purple Emperors, Apatura ilia, but I did not see them well enough to add to my list, and I did not see more. Here again the forest was lacking many of the species I would have expected, although White Admirals, Limenitis camilla, were out in some force, gliding with their splendid flight around the forest glades.

A White Admiral sipping moisture from the ground

Several Black-veined Whites, Aporia crataegi, were also to be seen, but other than more common species such as Large Skipper, Ochlodes venatus, and Lesser Marbled Fritillaries, Brenthis ino, Comma, Polygonia c-album, and Brimstone, Gonepteryx rhamni, little was showing.

One encouraging sign was that much work is being done in order to make the forests in southern Belgium more butterfly-friendly, with clearings being created, allowing the sun to reach the forest floor and wild flowers to flourish. We can only hope that these efforts will bear fruit in more favourable years to come.

A sign indicating a newly cleared area, in this case for Marsh Fritillaries, among other species

In the afternoon, I moved on to examine the chalky grassland areas nearby, but here again there was remarkably little flying, other than one Brown Argus, Aricia agestis. However, just as I was driving away, the gliding flight of a large, dark butterfly caught my attention, and I jumped out of the car. Finally, I had found at least one example of one of my target species, the Purple Emperor, Apatura iris. Unlike many butterflies, Purple Emperors never visit flowers, preferring instead mud, dung, decaying animals and other unsavoury items. This individual, a freshly emerged male, with his glistening purple sheen changing colour as it caught the sun, was highly cooperative, settling and probing the mud with his bright yellow proboscis as I photographed and filmed him for several minutes. I normally see many of both species of Purple Emperor in this area, and hopefully this was the first of many more that will emerge in the coming days.

A freshly emerged male Purple Emperor, showing how the purple sheen often appears on only one side, depending on the angle of the light

A video of this male Purple Emperor can be viewed below.

On my way back to the Netherlands on Monday 8th July, I stopped at a reserve on the Belgian/Dutch border, where I had some hopes of finding Alcon Blues, Maculinea alcon, but none were to be seen. However, there were numerous Silver-studded Blue, Plebejus argus, which are a kind of symbol of the Dutch heathlands (indeed in Dutch they are known as Heideblauwtjes, or Heath Blues). It was encouraging to see so many of these little jewels flying over the heather.

A female Silver-studded Blue perched briefly on a grass stem

2013 list total as at 9th July: 61 species