Cunning nest builders

High in my list of favourite nests are those of the Varied Sittella Daphoenositta chrysoptera. I remember wanting to see one since schooldays when I first saw a photograph of a nest, then when I visited Australia I wasn't disappointed. They are extremely craftily built and difficult to see, but last week I heard these birds busy in a tree above me, and there was another.

Sittellas are cooperative breeders, where there is one breeding pair and up to several helpers. The breeding female incubates the eggs, and broods the chicks; the others help by providing food, defending the contents from predators and of course, as seen here, they aid in the building of the nest.

The nest is constructed with spiders web and strips or flecks of paper-thin bark.

Their nests are typically set in the upright fork of a dead bark-less branch.

The birds deftly layer the material to fit within the fork and mold the bark flakes to flow with the contours of the branch.

All that material has to be shaped just right to fit the incubating bird, so I think this is the breeding female turning about on the nest.

Some of the birds came in with rather large beak-fulls of nest material.

Sittellas always land on branches in an upright pose.

Although they seem to prefer to walk down the branch to the nest.

Yet another shuffle to get it all into shape, then repeat.

Spring at last 
common and not so common, all welcome

My blog has been quiet for quite a while recently, a reflection of not inactivity but the opposite - high activity. Since migrating back south to Canberra in July I have been doing something in the field most days, and desk-work most evenings. I find that when I am busy I have less time to write up the blog, so readers, please be patient if you do not see anything new for long periods.

In a very brief summary, I arrived back in Canberra to a long cold dry winter which has dragged on into a long slow, cold, dry spring. At last the weather has warmed, it still hasn't really rained, although blossom is out, butterflies and dragonflies are flying and the birds are nesting.

This Bearded Dragon was basking on top of a cut tree limb yesterday, although the sky was overcast and it looked rather slow, as if not very warmed up. I took these shots in late afternoon, when they would usually be active and quick to react to approach. Although these are long-lens shots and I didn't disturb it.

I am always captivated by how Bearded Dragons' scales fit around their faces, each one, from the spines on the neck, to the lips and those amazing eyelids. Beautiful.

Bearded Dragons are common in the Canberra woodlands and they are a sure sign of spring. Much less common, in fact very rare at local, national and international scales is the Canberra Spider Orchid Arachnorchis actensis. This plant is critically endangered as it is only known from the Australian Capital Territory and only from three sites there. The bush is still very dry with very few plants of any sort throwing up fresh shoots, yet a group of these orchids, only several cm tall, were stretching up from the stony forest floor yesterday. rare jewels indeed. But it is not their rarity that appeals to me, it is their form, like that of the dragon, each flower part is beautifully formed.

Welcome back Spring.

Three alpine/arctic specialist birds

The path into Coire an t-Sneachda

I went for a walk in the Cairngorms last week, to count Ptarmigan Lagopus muta and their brood sizes, as they mostly have well-grown chicks now. Ptarmigan are an alpine/arctic bird so they are restricted to such ground in Scotland and if we want to see them we have to do so on their terms. Two other species which are such specialists are Snow Bunting Plectrophenax nivalis and Dotterel Charadrius morinellus, and I saw them both while looking for the Ptarmigan.

 

The castellated rim around the top of the corrie cliffs

I walked into the hills via Coire an t-Sneachda and took the Goat Track up onto the plateau. A fine spectacular route through a boulder field and under the crags.

The twin pinnacles from above the rim

I passed the common generalist hill birds, Wheatears Oenanthae oenanthe and Meadow Pipits Anthus pratensis in the corrie, and a couple of Ptarmigan, then as I neared the summit I heard a Snow Bunting singing. His song ringing around the rocks on such a clear windless day.

A handsome Snow Bunting singing from the edge of the cliff

When I reached the top, I sat on the cliff edge for a while and soon realised that the Snow Bunting was flitting between a few rocky points which he was using as song-posts, one right by me. And he was confiding, he seemed to accept my presence and came to sing next to me. He would fly from a cliff across a gully then slowly descend in a parachute drop to his post next to me, singing as he came down.

A cock Ptarmigan sits on a rock ledge overlooking the corrie floor 200m below

The Snow Bunting was easy to see as he was making himself conspicuous by his singing display. The Ptarmigan were much more secretive. But just around a rocky corner from the bunting I noticed a male sitting quietly and inconspicuously on a rock more fitting for a bunting song-post than a Ptarmigan perch. He was squatting there watching over his hen who was in the gully below, feeding on the mountain herbs, Heath Bedstraw Galium saxatile and Alpine Lady's Mantle Alchemilla alpina.

If he hadn't moved I would probably not have seen him

That female didn't have any chicks, and it was probably too late for her to re-lay if she had lost her first clutch of eggs. So they would probably have the rest of the season off from raising young, then join into a flock of failed breeders and males who would soon leave their partners to rear their chicks alone.

A hen Ptarmigan, she was alert and watchful as she had chicks
- a different colour from the males, more suiting to the heath and moss habitat

The next Ptarmigan I found was a female with four chicks, who were feeding on the top edge of the next corrie, where the herb-rich cliff vegetation merged into the sparse windswept plateau vegetation.

She had four chicks - two can be seen in this photograph

This was prime Ptarmigan habitat, a loose mix of boulders for cover from predators and weather, and food plants growing close to the base of the rocks. They would never have to wander far from cover to feed, and if it was difficult for me to find them it would be difficult for any predators. Such mountain habitat might seem harsh or inhospitable to some anthropocentric humans, but to Ptarmigan it is perfect. And I like it too.

The Cairngorms plateau spreads out above the cliff edge
Braeriach is the highest hill in the background

The high ground of the Cairngorms, above the cliffs, is mostly sweeping, rolling plateau. There are Ptarmigan throughout this habitat of wind-scoured boulders, gravel and Juncus trifidus heath, but the main specialist bird of this ground is the Dotterel. I have studied these birds for over thirty years, and although I am very familiar with them, it was still good to see some. They fit the landscape so well. Although waders, they spend their non-breeding time in arid north Africa, then fly north to breed on dry mountain/arctic heath. I have only once seen one stand in water. The birds in Scotland are one of a few species that can live on the highest ground, and select to breed only there. They were the third such alpine/arctic specialist bird species I saw that day, the high three.

A male Dotterel skulks in the alpine heath - mostly Juncus trifidus  

I wasn't there to study Dotterel that day, so although I did see a few, I walked on by. The males mostly had chicks - they incubate the eggs and rear the chicks alone, but this one was with a female, so he had perhaps lost his first clutch and she might have been about to lay another for him. 

He showed himself briefly as he ran between the tussocks

The female Dotterel are bigger and brighter coloured, but she never showed herself clearly and I didn't chase her. I have seen hundreds before. I simply appreciated them, took a few long-lens shots as the male popped close, and I walked on by. There are too many human visitors, hillwalkers and bird-watchers to that area, I didn't want to add to their disturbance.

I was happy, I had spent a perfect day in my favourite habitat, one I share with three special birds.

Defence strategies of tundra birds

A male Spotted Redshank comes close in defence of his chicks

I spent the past two weeks in northern Norway studying birds, mostly waders and even though I am familiar with them, I continue to be impressed by the efficiency of their stategies in defending their eggs or chicks.

A Spotted Redshank can hide or run when a predator approaches

Most Spotted Redshank pairs split soon after the eggs are laid and the male incubates them, then rears the chicks alone. The chicks stay in the nest for the first day then they can walk more than a kilometre to reach a feeding marsh.

An male adult Spotted Redshank in breeding plumage - no other bird like it 

When danger approaches, the adult flies close to the intruder and pipes loudly, very loudly, causing confusion in a potential predator's mind - mine anyway. Meanwhile, the chicks run away or hide until the danger passes.

Incessant piping

Other waders, such as Whimbrel fly up and around any potential predator, calling in alarm, or guidance to their chicks. We as humans, cannot tell which, but the chicks can either run or hide. What vocal signals do the adults give to do either?

A Whimbrel up a tree - from where it is safe from ground predators and it can see its chicks hiding in the ground vegetation

The main terrestrial predators are Red Fox and Stoat, but there are also Ravens and Hooded Crows which can take the chicks. Perhaps that is one reason why the chicks can either hide or run.

Wood Sandpipers habitually sit in trees when protecting their chicks

The waders usually have four chicks, so scattering to feed, hide or run gives the others a chance if a predator finds one of the brood.

When on eggs =- Wood Sandpipers sit tight on approach

If they have eggs, these birds usually adopt a different strategy, one of sitting tight on their nest, relying on camouflage and concealment to avoid detection by any predator, until the last moment when they burst fom their nest to escape capture.

very tight

Once they leave their nest, these waders will call in alarm, then either fly away and try to distract the predator, or adopt a rodent-run display, where they either impersonate a rodent or a bird with a broken wing to lure the predator from their nest.

A Broad-billed Sandpiper gives a distraction display, pretenting to be a rodent or have a broken wing
- to lure me from its nest and eggs 

If anyone has been with a dog when it has disturbed a nesting bird they will know how efective this display can be. Most dogs, especially town dogs fall for this trick and run after the bird well away from the nest.

Jack Snipe sit extremely tight on their nests 

Jack Snipe are one of the tightest sitting waders, I am sure I must have stepped over birds on their nest. And when one sees how well they are camouflaged in the mire vegetation, I know why.

Jack Snipe nest just above the water level below the marsh vegetation
- they see the habitat differently from we humans 

It is not only waders which behave like this, other ground nesting birds act similarly, such as Willow Grouse. They have larger clutches and broods, perhaps 7 - 11 eggs or chicks, so the scattering of the brood if they run or flutter away is especially successful at saving at least part of the brood.

You all saw the male Willow Grouse, on the right first, maybe then seeing the female afterwards

Their chicks are most vulnerable in their first week, but after that they can fly in a fluttering flight for several metres, then more as they age.

A two-day old Willlow Grouse chick sits quietly and motionless - to avoid detection while its parents try to distract me

The male grouse is more brightly coloured than the female, and this one was more demonstrative to me. The female was running around low and farther away from me. That way, if any predator managed to kill any bird it would likely be the male. He is more expendable, if he died the female could rear the chicks by herself. So, a test of his fitness as a mate is not only his bright plumage, but his ability to escape predation which that plumage might attract.

The male Willow Grouse came within metres in attempting to lure me away from his chicks

Remote Mountain Top Sunset

Settled weather, dry underfoot and clear skies. The time had come for me to head off into the Fisherfield hills in the north-west Highlands to catch the sunset from one of the more remote hills in the country, Beinn Tarsuinn. This meant a 15km walk, so I left at 1700, following the glen to the Heights of Kinlochewe and beyond. After that, Slioch another fine hill, kept me company all the way.

I was heading into the sun as it slipped around behind Beinn Tarsuinn, with Meall Garbh and Mullach Coire Mhic Fhearchair on its right.

The initial view from the summit was stunning, all around. All quiet, only me. Soft light and a soft wind. Easy relaxing conditions. Then the sun began to dip quickly and the light, the colours, the scene were changing by the second. There was so much to see, to take in.

I had timed my arrival perfectly as the shadows were just beginning to lengthen and fill Gleann na Muice. An Teallach, the hill featured in this blog two posts ago, lies at the foot of the glen, with the distinctive jagged ridge of the pinnacles clearly visible. The scene of recent fun.

A ninety degree panorama of the hills lying to the south, Slioch fills the mid left ground with the Torridon hills behind. Loch Garbhaig and Lochan Fada lie in the centre.

A ninety degree panorama to the north-west, the sun dipping behind A' Mhaighdean, with the pointed peak of Ruadh Stac Mor next to the right.

Most of the hills in these ranges are formed from Old Red Sandstone, which looked splendid in the setting light. Later, once dark, the grey patches of lichen shone in the moonlight.

My main objective of this trip was to catch the setting sun over the table-top section of the ridge leading west from the summit of Beinn Tarsuinn. Years ago, I watched the mid-summer sunset from the neighbouring peak A' Mhaighdean, which the sun is dipping behind here. That is regarded as one of the most remote mountain tops in Scotland, and I like remote. That was a great night, but I reckoned the view fron Beinn Tarsuinn might be even better. Now I have done both, I reckon both are good, just different.

The mini plateau has been dscribed as a tennis court and billiard table. And like all such cared for game sufaces, it should be looked after. So please do not be tempted to go and camp there. You will ruin the fragile vegetation cover and spoil the whole experience of other people who like to to see it in its natural state. I demolished one ring of stones that had been left there by campers. No more.

Fortunately the table-top is a bit askew, and a bit sparse of grass. Any tennis balls would lkely go over the edge.

Beinn Lair and Beinn Airigh Charr fell asleep in the deepening shadows.

The sun finally set behind a bank of cloud out at sea, at about 2220. Then the western sky took a rose tint.

I took that as my cue to leave the stage and headed off down to the bealach between Beinn Tarsuinn and Meall Garbh. But it was too fine a night to go down to the glen yet, so I clambered up the rock staircase to the summit of  Mullach Coire Mhic Fhearchair. It was dark by the time I reached the top and going down would have been a bit more tricky if it weren't for the timely appearance of a full moon from behind a line of cloud in the east. That was at about 2330.

From then on, I was guided by the moon down the rocky ridge, across a steep mountain path, down over the moorland and along a path to the main glen at Kinlochewe.

The first cuckoo called at 0240, and a ring ouzel at 0255. After that wheatear, grasshopper warbler and stonechat added a chorus.

The moon's reflection sparkled on the lochans as I wandered down the slopes. And I wondered at yet another unforgetable experience in the hills.