Sunday 4th August 2013

Butterflying in the outer isles

I am just back after an amazing 10-day trip to the Outer Hebrides, those isolated, wind-swept islands off the north-west coast of Scotland. Not surprisingly, considering both their climate and their geographical isolation from the mainland, the islands’ butterfly list is short, with only 15 species, some of which are only occasional migrants.

Despite this overall poverty, numbers of some species are impressive, and in my short visit, I managed to find 9 of the 15. Perhaps the butterfly of the trip was for me the Large Heath, Coenonympha tullia, which I found on the mainland near Ullapool while waiting to catch the ferry, on Harris in considerable numbers wherever cottongrass was to be seen on the peaty ground, and on North Uist, where some were even to be seen in the flowery “machair”, the sandy, lime-rich grassland found in a strip all the way down the western coasts of the islands, a habitat where I might have expected Small Heaths, C. pamphilus, which I did not see at all.

A Large Heath feeding on Eyebright, a common flower on the islands

The commonest butterflies were undoubtedly the Green-veined White, Pieris napi, which abounded, emerging from the damp vegetation when even the slightest gleam of sun appeared, and the Meadow Brown, Maniola jurtina, which here is represented by the brighter subspecies splendida. These butterflies were everywhere, occurring in all habitats I visited.

A visit to the far northern tip of the island chain, the Butt of Lewis, added two species to my 2013 Scottish list: Large White, Pieris brassicae, and Red Admiral, Vanessa atalanta. These are both migrants, and they seemed to be still heading northwards, although if they headed out to sea, they would certainly be doomed, as the likelihood of their reaching either the Faeroe Islands or Iceland, the only land between here and the Pole, must be negligible. Either they know they have to stop here, or they head out to sea and eventually tire and die. It is a sobering thought.

Cliffs at the Butt of Lewis, beyond which butterflies venture at their peril

Common Blues, Polyommatus icarus, were also in evidence on the flower-rich grasslands just behind the cliffs, as they also were further south, in the Uists, my next destination.

A Common Blue perched beautifully on a lichen-covered rock

North Uist turned up Small Tortoiseshell, Aglais urticae, while further south I came into contact with an additional two species that do not occur on the more northerly isles: Dark Green Fritillary, Argynnis aglaja, several of which were to be seen both on the machair close to the southern tip of the island, and on the offshore island of Eriskay, and Grayling, Hipparchia semele, one of which posed kindly for me to photograph, also near the southernmost point of South Uist.

A cooperative Grayling at the southern tip of South Uist

Outer Hebrides total: 9 species

Scottish 2013 total as of 4th August: 15 species

nextpost

Wednesday 24th July 2013

Graylings on the rocks

Having reached 13 species of butterfly since I arrived in Scotland, I find myself hard-pushed to find any others! There are still perhaps another five I could find before I return to the Netherlands at the end of August, but these have not yet emerged.

Despite this obstacle, I am nonetheless seeing plenty of butterflies. Common Blues, Polyommatus icarus, are commoner this year than I have ever known them, Green-veined Whites, Pieris napi, are out in force, and Ringlets, Aphantopus hyperanthus, are in evidence in almost all damp habitats.

A visit to the far southern end of the Machars peninsular, near Isle of Whithorn, produced much better views than I had previously obtained of that specialist of rocky terrain, the Grayling, Hipparchia semele. The low cliffs here, with their warm, south-facing, wildflower-covered slopes provide ideal conditions for these vigorous butterflies, which chase each other across the steep slopes, landing every now and then on the rocks, where their cryptic camouflage renders them almost impossible to see.

A warm, sheltered gully, favoured by Graylings, which settle on the rocks to take the sun

Obtaining a photograph of the Graylings on the steepest slopes was impossible, but luckily I came across one feeding on a flower-head at the top of the cliffs, which allowed an extremely close approach – although as usual, grass-stems blocked the camera’s view.

A Grayling lurking behind the inevitable grass stems

The Grayling, with an almost grass-stem-free view – but not quite

Today I am heading northwards to the Outer Hebrides, where again I am unlikely to add much to my list, but it will be interesting to see what species I can locate on those remote, windswept islands in the North Atlantic.

nextpost

Friday 19th July 2013

Boiling in Scotland!

We are currently enjoying a spell of incredibly warm, sunny weather here in Scotland, and the butterflies are appearing at last – not that there are many new species for my overall list here, but the numbers are encouraging.

On Tuesday 16th July, we visited the beautifully located Corsewall Point, at the northern end of the Rhins peninsular, offering panoramic views to Arran, Kintyre and the Antrim coast of Northern Ireland, with the pudding-shaped rock of Ailsa Craig towering out of the Firth of Clyde in the middle distance.

In addition to large numbers of Common Blues, Polyommatus icarus, the vegetation just above the rocks produced numerous Meadow Browns, Maniola jurtina, and a few Green-veined Whites, Pieris napi. Here I was able to locate a new species for my Scottish list, Small Heath, Coenonympha pamphilus, of which at least three were quite vigorously defending their territories against passing Common Blues. Small Heaths, formerly common and widespread in Galloway, seem to have declined noticeably in recent years, so it was encouraging to see these individuals here.

A rocky area at Corsewall Point, Wigtownshire

Down at the very bottom of the rocks, just above the tideline, two larger, more boldly marked butterflies flew by, and a binocular view revealed them to be a new species for my overall as well as for my Scottish list for 2013, the Grayling, Hipparchia semele. I was unable to approach them in the hope of obtaining a photograph, but as this species is widely distributed around the rocky areas of the Galloway coastline, I should see several more before their flight season ends.

Wednesday 17th July saw me walking up the 711 m Cairnsmore-of-Fleet, our local hill. Following another Small Heath, once I had passed through the first belt of woodland, I came out into a relatively recently felled area, and fairly soon spotted a rather faded butterfly gliding over the bracken. This turned out to be a Small Pearl-bordered Fritillary, Clossiana selene, a new species for my Scottish list. I later went on to see four of these, all looking close to the end of their lives.

A Small Heath, a formerly common butterfly in Galloway

Also in this zone there were numerous Ringlets, Aphantopus hyperanthus, and a few Meadow Browns, Maniola jurtina. A little further up, particularly where a forestry road crosses the main hill path, an open area held several Common Blues, Polyommatus icarus, and another new species for Scotland in 2013, the Dark Green Fritillary, Argynnis aglaja. At least 25 of these splendid gingery-brown butterflies (their name refers to the ground colour of the underside of their hindwings, with the incredible silver spots setting off the green ground colour) were sailing about of the bracken, the males chasing the females, at least one of which I observed fluttering low through the grass, searching for violet plants on which to lay her eggs.

A Dark Green Fritillary, showing its green background colour with the silver spots

Today, Friday 19th July, has again been a blazing day, and a short walk this evening added two new species for my 2013 Scottish list: Peacock, Inachis io, and Small Tortoiseshell, Aglais urticae, bringing the total up to 13 species.

2013 butterfly list as of 19th July: 68 species

2013 Scottish list: 13 species