Eagle nests are large

A typical Golden Eagle eyrie site in Scotland
set on a broad vegetated ledge behind an old Rowan tree 

The golden eagle Aquila chrysaetos chicks are now large enough to ring and I visited this nest a few days ago with Adam Ritchie, a fellow eagle researcher. Simon Cherriman, a friend and another eagle researcher - mostly of wedge-tailed eagles in Australia - helped and gained experience of how things are done in Scotland.

The chick is about 30 cm long and 20 cm broad, so this is a deep wide eyrie 

It was good that Simon came to this eyrie, for as the two of us roped down to the nest I was reminded of the size of these nests. I don't always appreciate that when alone. But with another person on the nest the scale became clear. The nest was huge.

Simon measures the length of the chick's head and bill
there is room for two people and the chick on the nest 

The chick was ringed and measured within minutes, a minimal intrusion when the adult birds are often away from the nest for hours when the chicks are this age or older - this chick was about four weeks old. Although I am sure the adult birds would have been watching us from a distance all the time.

The trailing edge on the foreground of the nest is the birds' landing platform, they don't flop down
 onto the nest but glide and stall onto the lower edge, then walk up onto the platform.
It also shows how easily the birds can launch themselves out onto the air straight from the eyrie
- there is a lot of space below

Misty Cotton

There has been an east coast fog recently under the continuous cool north-east wind. In north east Scotland, this mist is known as the haar. In the evenings it creeps in over the land and one evening this week it was lying low on the moors. Meanwhile, it is the season for the cotton grass Eriophorum vaginatum to set seed, and this year there has been a splendid crop of the white cotton heads. The two features together make a soft delicate landscape. A transient tapestry.

The individual plants of the cotton grass grow in tight tussocks on the wet moorland, bog really, known as mosses in the north-east. These cotton buds shine bright white in the sunshine, but in the diffuse evening light, the details of their silky tufts are the showpiece. Whether in close up detail or en masse.

When looked through from ground level,the sea of white rolled on and on, one snowflake after another, forming a fluffy bogland blanket.

The hedgerows are full of white blossom at the moment, but the cotton grass even up-staged them. This was a truly spectacular sight, a soft but spectacular sight.

Late season - Ptarmigan just laying up

A cock rock ptarmigan Lagopus muta sits on top of a rock watching over his mate as she feeds below

Although the weather has been clear, dry, sunny and warm in the Scottish Highlands over the past week, the ptarmigan are late in laying their eggs this year. A sign of how cold the weather had been before the current warm spell.

Ptarmigan habitat of short, wind-swept heath on the high ridge of Ben Klibreck

I was up Ben Klibreck in northern Scotland a few days ago, and other hills since, recording the food plants that ptarmigan were feeding on. The females should have been incubating their eggs by now as they often hatch in the first week of June, but this year they seem to be about two-three weeks behind their normal schedule. Ben Klibreck is 961m high and the ptarmigan habitat extends down to about 650m. So, any effects of a cold spring will be especially evident at that altitude, and the leaf buds of their main spring food plant in Scotland, bilberry Vaccinium myrtillus were only just opening.

A pair of ptarmigan in their mountain habitat - the cock is grey, suiting the colour of the rocks that he spends most his time amongst, as he watches over his hen. She is a dappled brown colour, suiting that of the short heath she is feeding in. 

At this time of year, the cock ptarmigan stay close to their hens, guarding them from competitors and keeping a watch for predators, mostly golden eagles in this area.

A hen ptarmigan in full breeding plumage

This hen seemed to be heavy at the rear end, she probably had an egg well formed in her egg duct which would soon be ready for her to lay. Compare the profile of her body beneath her tail with that of the cock bird's slimmer line.

A cock ptarmigan his full breeding plumage

Part of the reason for the bird's lateness in laying is probably due to the late development of the birds' food-plants. These are sparse in the north-west Highlands, and although the ptarmigan do live there successfully on what seems to us seems a scant food supply, to form a clutch of eggs, the hens might need the extra nutrients that the developing new growth brings.

Sparse food plants for ptarmigan amongst a carpet of woolly fringe moss

The bilberry was growing in short, thinly scattered sprigs, and there was a similar scattering of stiff sedge Carex bigelowii. I watched one hen picking out the flower spikes from the sedges, delicately and precisely nipping off only the most nutritious parts and avoiding eating much of the stems which are less nutritious. Another food-plant there was alpine lady's mantle Alchemilla alpina, of which they eat the flower buds as they form, but few had formed by last week.  All three food-plants were growing in a carpet of woolly fringe moss Racomitrium lanuginosum, which made up about 90% of the ground cover in places. By living there on such meagre food supplies, the ptarmigan were showing once again how well they are adapted to life on the high tops.

Flower spikes of Stiff Sedge and opening leaves of Bilberry - the two main foods that the ptarmigan were eating that day. 

Windy sea cliffs

A small section of a colony of Kittiwakes Rissa tridactyla 

A few days ago the weather was forecast to turn windy and wet, so I took a day out to visit the seabird colonies on the north-east Scottish coast, where the rain would reach last. I timed it right and I had a great time watching the birds flying in the wind, the clifftop giving me an eye-to-eye view of them in flight. So different from standing low on land or a boat looking up and only seeing their bellies.

A Kittiwake cruises past me at cliff top height, feathers ruffled by the wind

Windy days are also best for watching and photographing them as they often stall and hold themselves stationery in the wind, without any need to flap their wings. From my high perch, I could see how the wind ruffled and tugged at their feathers, flight is obviously not always smooth.

A Kittiwake flying with its feet down - controlling its speed with them|?

Most of the birds were holding their feet down, using them as extra aids to flight in strong wind.

A Fulmar similarly flying with its feet down

The truly specialist fliers on these cliffs are the Fulmars Fulmarus glacialis. One minute, they would cut through the wind at high speed, the next they would float up on an updraft, holding themselves in one spot by the slightest of flicks of wing, tail or feet. They seemed to be inquisitive and deliberately approached me as I sat on the cliff top, watching me eye to eye before slipping off on the breeze.

A Fulmar on wide-spread wings tilts to steer, but holds its head level all the time

The dull grey skies gave low light for photography, limiting the speed I could shoot at, but the positive aspect of the low light was the colour saturation I could capture. Photographing seabirds on sunny days can be very tricky as most of them are black and white. Under bright light it difficult to capture the details of their plumage due to the sharp contrast. The light was growing darker as the clouds thickened, but I managed to grab some shots that showed the feather details; how they lie when in flight, the different shades and colours of the fresh and old feathers, the smudges of dirt and guano on their breasts, and the fine lines on their faces, bills and feet.

Every cloud has a silver lining.

It's not easy for seabirds to keep clean when they are nesting on dirty ledges

Montane moths

The twin peaks of Spidean Coinich on the southern ridge of Quinag

After a long cold spell, last week the weather turned bright and warm, although still with a brisk northerly wind. The tops of the hills in the Scottish Highlands cleared and walking there became relaxing and warm compared with the previous week. So I headed up Quinag in Assynt, in the north-west Highlands for a short day on that magnificent little mountain.

Lochan Bealach Cornaidh in the eastern corrie of Quinag

I began my walk started from a car park set on a high pass at about 250 m, then meandered through the main corrie, past Lochan Bealach Cornaidh and up the last short steep slope to the summit ridge. The ridge splits into three, leading to the triple peaks. The shortest ridge rises gently up to Sail Gharbh, the highest top at 808 m, which is nice and convenient for a short day.

The view south from near the summit of Sail Gharbh, the highest peak in the Quinag massif. Canisp, Cul Mor and Suilven rise up behind Spidean Coinich

Down in the corrie, the heather is tall and mixed with purple moor grass Molinia caerulea, the dominant grass in these wet heaths. Higher up, the heather becomes shorter as it becomes more exposed to wind. The result is a short sward of mixed heather, grasses and mosses. A soft carpet covers the ground between the scattered boulders making the walking easy for us but living hard for all except the best adapted plants and animals. Ptarmigan are there, although scarce as their preferred food plants of bilberry, and crowberry are sparse, and other foods such as alpine lady's mantle and heath bedstraw are similarly thin on the ground. There were a few wheatears and meadow pipits, hunting for insects and those insects were hiding, such as the Broad-bordered White Underwing moth Anarta melanopa.

A well camouflaged moth sits on the prostrate heather high on the ridge, the grey mottled forewings match the colours of the mosses and the pale border of wings matches the twists of white grasses, 

The main range in Britain for this species is withiin the more central Highlands, such as the Cairngorms, so it was especially pleasing to find several individuals out basking in the May sunshine on this north-west hill. They were mostly keeping still, but when any flew they were distinctive in their low tumbling flight, being buffeted by the wind.

A Broad-bordered White Underwing moth, a true mountain moth that only lives on montane heaths

Like all animals that live on the high ground these moths have adaptations that give them the ability to survive there. Camouflage is one, and insulation from cold is another. The adults sip nectar from the flowers of the heath plants; bilberry, crowberry and bearberry, which are also the foodplants for their caterpillars. These heaths thrive better on the slopes and lower hilltops, rather than the highest summits in the Highlands, so the smaller hills in the north-west probably suit them and they might be more abundant there than what has been recorded. I'll take notes on other places I find them in future.

The moths' bodies are clad in a 'fur' of modified scales, even the scales on their wings seem to have a furry texture. All adaptations for life in a cold environment on the mountain tops.

My day was short on the tops, I had to go back to the valley and the warmer environment. Even with the best of waterproof and windproof clothing I would become cold if I stayed there overnight, and I would become hungry. I like being up on the tops, but I am not adapted to living there. That takes a special type of animal or plant, and I admire them.

One pair of moths were mating.The warm weather had encouraged them to emerge from their over-wintering state and the main purpose of any adult insect is to breed. The warm period can be short and unpredictable in the hilltops, so they must take the first chance to breed that have. It might be their only chance if a period of cool wet weather settles in before their short life ends.