walkhighlands

The Cuckoo: a wonderful summer madness

Ben Dolphin

Have you ever tried to creep up on a cuckoo? I’ve tried repeatedly over the years but it’s nigh on impossible. I suspect even the SAS would struggle.

Cuckoos are impossibly flighty, and somehow also evade being precisely pinpointed by your ear. A vague direction can be discerned, but when you think you’re getting close, the call suddenly seems to come from another direction entirely.

It could be another cuckoo of course, but more often than not, your target cuckoo has simply taken flight and moved to a new location. You didn’t see it move because….well….what would that even look like? You’ve never seen a cuckoo, and you have absolutely no idea what they look like.

I don’t remember where and when I saw my first cuckoo, but it certainly wasn’t at close quarters. The first I actually managed to photograph was in 2016, while cycling around Loch Katrine. The bird was still some way off, and thus established a now time-honoured motif in my nature photography: that of the tiny, grainy and blurred cuckoo on maximum zoom.

My first ever cuckoo photo, at Loch Katrine. It set the bar pretty low!

I’ve long since stopped trying to creep up on cuckoos. It’s difficult, time consuming, and I’ve made peace with that. I’ve come to accept that hearing their call echoing down a glen is satisfaction enough.

So imagine my surprise, early in May this year, when I found myself staring at a cuckoo just three metres away!

There’s a dead plant outside my house. It’s just the dried stalk from last summer, but my other half wanted me to cut it down because it’s 4ft high and right outside the kitchen window. I’d have got around to doing it eventually, but there I was one morning before work, sipping coffee at the breakfast table, when a large grey bird whizzed from stage left and landed on the stalk.

For a few seconds I thought it was a sparrowhawk, but the penny quickly dropped and I was, frankly, astonished.

When you’ve actively tried (and failed) to get close to a cuckoo so many times over the years, it’s downright surreal to have one in plain sight without having expended any effort whatsoever. Face to face with a bird so elusive it’s almost mythical. But yep, there it was.

Snapped from my kitchen window!

I’d seen cuckoos in pictures of course, but there’s no substitute for actually studying one up close. They have a peculiar appearance. Not because they look peculiar in themselves, rather because they look so much like a bird of prey. Specifically, a sparrowhawk.

About 1ft long, cuckoos are of similar size to male sparrowhawks. They lack the hooked beak and long legs of a sparrowhawk, but they do have the same blue/grey plumage, and distinctive hawk-like barring on a pale chest.

Even in flight, with their long tails and purposeful flapping of pointed wings, cuckoos are strikingly similar to a merlin or a kestrel. There is of course a reason for this likeness, but more on that later.

I watched this cuckoo outside my window for about 10 seconds. By the time I grabbed my camera, it had flown 10 metres further away to a fence post. But even there, it was as good a view as you could ever hope to get.

Over the last few weeks, I’ve found myself sitting at the breakfast table, staring intensely at this dried husk of a plant, in case the cuckoo lands there again. Happily, it’s perched a couple more times that I’ve seen, so suffice to say, I’m never cutting the weedy husk down now!

A watched kettle very occasionally boils

I realise I’ve been immensely privileged. Having at least two cuckoos hanging about outside my house has meant I’ve learned more about them in that time than in all my previous years combined.

One, presumably the male, staged a peculiar courtship display after he’d perched. He stuck his tail up in the air, hung his wings low down beside him, and then started wagging his bum from side to side.

On another encounter, as I was cycling to work, I watched and listened as a cuckoo flew parallel to me, chattering constantly. I was taken aback, because while I assumed they probably made noises other than ‘CUCKOO’, I had no idea for sure, nor knew what those noises would sound like.

I’ve since learned that this peculiar, almost laugh-like chatter is made by the female. And to my surprise, I now realise it’s a sound I’ve heard quite a lot over the years, without realising what was making it.

The female doesn’t make the ‘CUCKOO’ call. Only the male does that. And what a call it is!

“CUCKOO…….CUCKOO…….CUCKOO……”

It’s easily one of the most recognisable of any bird, which is surprising really, given how few of us actually get to hear cuckoos these days. Nevertheless, nothing else sounds like it.

Students of music talk fondly of the call, on account of the interval between its two notes being a tuneful minor third. I love hearing it for its weird tunefulness, but also because it tends to suggest that the landscape it inhabits is still in some degree of good health. The presence of cuckoos not only indicates a good population of the cuckoo’s target nest species, but also of the cuckoo’s favoured food – hairy caterpillars.

Their call carries so far, and is so clear and precise. Bound up in folklore across Europe, the cuckoo is a cherished spring companion, but you can possibly have too much of a good thing.

The TGO Challenge, an annual coast-to-coast mass participation walk across Scotland, always happens in May, which is ‘peak cuckoo’ up here. And when the Challenge was passing through Mar Lodge Estate last month, I got chatting to a lady who’d started her challenge in Acharacle, and had then gone up Loch Shiel and through Glen Pean.

She was telling me of the wildlife she’d seen along the way, and said that although she’d heard far more cuckoos out west than in the Cairngorms, she’d said they’d nonetheless been constant companions the whole way.

“Ha ha, what was that like?”, I asked, knowing exactly what someone who has been under canvas every night was likely to say.

“Ugh, 5am every morning!! Between cuckoos in the morning, and tawny owls at night……” she trailed off, feigning a fatigued expression that made me laugh.

I know exactly how she felt. Back in 2018, during my first ranger season at Mar Lodge, I lived in what was affectionately called ‘the dog flat’, on account of it overlooking the kennels. Ear plugs worked to a point, but they never really managed to fully drown out the barking.

The cuckoos have been regular visitors to the garden recently

A month into my 2019 contract I was offered the chance to move into a flat in the lodge itself, and I still remember opening the new bedroom window that first afternoon, after the move, and hearing……..nothing. Nothing but….

“CUCKOO…….CUCKOO…….CUCKOO……”

Oh, it was so peaceful. And the cuckoo was calling as if to really ram home what a special, idyllic place this was. It was a beautiful serenity.

Next morning, at 6am:

“CUCKOO…….CUCKOO…….CUCKOO……”

And the morning after that:

“CUCKOO…….CUCKOO…….CUCKOO……”

I was charmed at first. But before long I was wondering whether barking dogs might be the greener grass after all, because that cuckoo wormed its way into my head in a way that the rest of the dawn chorus didn’t.

The dawn chorus is more of a general background presence. Ever-changing, with different songs, tuneful calls and squeaks coming and going. No five seconds are ever the same. It can be loud, yes, but I find that it can also be indistinct enough to be background noise.

But the cuckoo. Well, it just goes:

“CUCKOO…….CUCKOO…….CUCKOO……”

That’s it. That’s all it does. Over and over and over again. Eventually I had to dust down the ear plugs.

I don’t know where the saying about ‘going cuckoo’ comes from, but I wouldn’t be surprised if it has something directly to do with long, bright mornings in late spring, and failing to get a good night’s sleep on account of that repetitive sound being drilled into your head. Being driven cuckoo by a cuckoo.

That said, cuckoos really aren’t here for long, so going cuckoo is a relatively fleeting summer madness. It’s arguably more of a springtime madness, as the adults arrive back in the UK in late April to early May, and are generally gone again by June or July. But I’d be the first to admit that when their call stops sounding out in early summer, the glens feel terribly empty.

Cuckoos spend most of their year on migration, or in their wintering grounds in sub-Saharan Africa. They return to the UK to breed, and while it might seem odd to leave so quickly when there’s a family to raise, remember that the cuckoo plays no active role in raising its offspring. It leaves that job to unsuspecting birds of a completely different species, and is therefore known as a ‘brood parasite’.

As many as 50 bird species have been found to have been parasitised by cuckoos in the UK, but in Scotland it tends to be meadow pipits, dunnocks and warblers.

The female cuckoo watches the landscape carefully, identifying target nests and then choosing her moment, ideally (but not necessarily) when the nest is left unguarded.

This is apparently where her sparrowhawk likeness comes in handy. Studies involving dummy birds with and without the distinctive hawk barring, found that smaller birds are less likely to mob a bird WITH barring. It’s also thought that her chattering call mimics that of a hawk, and thus discourages smaller birds from ‘having a go’.

Superficially similar. Sparrowhawk on the left, cuckoo on the right.

The time between her landing at the nest and departing again, having laid a single egg, can be astonishingly quick. A matter of seconds. And she’ll repeat this process in as many as 20 different nests throughout the breeding season.

Target host species might attack the cuckoo, and in some cases will reject the imposter’s egg. But more often than not, the host suspects nothing and incubates the cuckoo egg like it was its own.

Famously though, the grimmest aspect of the cuckoo’s astonishing lifecycle occurs just after the cuckoo chick has hatched. If it hatches out and there are still rival eggs in the nest, the blind, naked chick instinctively manoeuvres each egg onto its back, and pushes them out of the nest. It does the same to any live chicks that might successfully hatch out. I’d recommend going and finding footage if you’ve never seen it. It’s amazing really.

The result however, given that cuckoos are typically more than twice the size of their target species, and up to six times their weight, are tiny wee foster parents run absolutely ragged. You can well imagine just how hard these wee birds have to work to satisfy the monstrously-sized cuckoo chick’s insatiable hunger.

Meadow Pipit. One of many unsuspecting host species.

Perceived as cruel and merciless, this clinically and coolly executed parasitism hasn’t proved universally endearing over the years. I stumbled upon a bizarre column in the Northern Echo this week, from 20 years ago entitled ‘Perhaps we are best rid of the cuckoo’. The author was practically rejoicing at the cuckoo’s steady decline, on account of the poor wee helpless birds it kills every year in the nest. Utterly bonkers, projecting our human values onto nature and thinking we’re best without something on account of it offending our delicate sensibilities.

As horrifying as some find this parasitic behaviour, the thought of the cuckoo vanishing from our landscapes is the only truly horrifying thing about the bird. Because yes, there is a marked decline occurring in the UK, down 65% since the early 1980s.

According to the British Trust for Ornithology (BTO), cuckoo abundance plunged by 34% between 1995 and 2020. But interestingly, that decline is almost entirely borne by the English population of cuckoos, for the Scottish abundance is up almost 70% in the same period, with a marked increase since 2010.

Studies do indicate that cuckoos have generally moved out of lowland agricultural landscapes in the UK, where their favoured moth prey species have declined significantly, in favour of wetland or upland habitats.

Until recently though, it was difficult to even guess what challenges cuckoos faced. Indeed, once their summer mating duties are done, it was something of a mystery where exactly cuckoos even went. Until, that is, an innovative and groundbreaking study by the BTO was undertaken.

In May 2011, they caught five adult cuckoos in East Anglia. Each was given a name (Clement, Martin, Lyster, Kasper and Chris), and was fitted with a tiny, lightweight, solar-powered satellite tag. The cuckoos left the UK in June, and then the BTO sat back and watched as the data came in.

Crucially, anyone and everyone could sit back and watch too, because there was (and indeed still is) a fantastic cuckoo tracking website. I remember vividly how, back in 2011, it was the first such real-time nature data to really grab my imagination. I would check it every other day to see where the cuckoos had moved on to, and it remains a superb example of how technological advances have revolutionised our understanding of an endangered species.

The project discovered that there were two migration routes for UK cuckoos.

All of the UK birds crossed the English Channel and headed south from there, but at the Mediterranean they split into two. Some would go through the Iberian peninsula and cross into Africa that way, whereas others headed down through Italy and made a much longer sea crossing. But regardless of route, they all ended up very close to one another in sub-Saharan Africa, in the Congo rainforest. The GPS locators were accurate to 500m, which isn’t much use at a very local level, but on a global scale represents pinpoint accuracy.

The project also found that although the Spanish route takes longer, an extra 1500km, all the birds, regardless of their outwards route, came back via Spain.

However, the BTO quickly ascertained that the outward Spanish route was a more hazardous undertaking for UK cuckoos, as it had a much higher mortality. Interestingly, tagged cuckoos from Wales and Scotland generally took the safer Italian route, whereas birds in England took a mixture of the two. And as we’ve already seen, it’s the cuckoos in England that have suffered significant decline. It led the study to conclude that:

The proportion of birds using the less successful route via Spain correlates strongly with the local population decline in the UK’.

The general decline across the UK is still under investigation, but is thought to be caused by a combination of problems both here and elsewhere on their migration. Theories about climate change in Iberia, and how the availability of food impacts upon a cuckoo’s fitness for the subsequent journey are being discussed, but more data is needed.

To that end, cuckoos have been tagged in the UK every year since 2011 (except 2020). Over 100 birds in total, each one adding weight to an expanding dataset. The project is still very much still public-focused, with a great website where you can meet this year’s cohort, see their photographs, and track the progress of previous birds such as Bowie, Disco Tony and Mr Conkers. The regular updates make for fascinating reading, and you can also sponsor a cuckoo, in order to help this groundbreaking project continue.

I’d encourage anyone to take an interest and follow the cuckoos’ travels, and learn a little more about these extraordinary birds. Truth be told, when they spend as little as 15% of their year here in the UK, cuckoos are barely a British bird at all. But it’s testament to their enduring fascination and appeal, and to their place in the cultural history of our landscapes, that so fleeting a visitor can have such a lasting impact in our imaginations.

Yep, the cuckoo does occasionally drive me cuckoo, but it’s a wonderful summer madness that I’m delighted to indulge.

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