MILLIONS AND MILLIONS OF MONARCHS

In the winter of 1974, in the high mountains west of Mexico City, Ken and Cathy Brugge found a few dead monarch butterflies lying tattered by the side of the road. It was exactly what they had been searching for, and sure enough, with a little exploration of the forests in the vicinity they uncovered the answer to one of entomology's great unanswered questions- where did all the eastern monarchs go in winter? The monarch is a common butterfly in North America, but come winter they simply vanished with no apparent trace. No eggs, larvae or pupae were ever found during those months. 

It was known that thousands of adults gathered in the Monterey pines on the west coast. But they were the ones from the west of the rocky mountains. What happened to the vast majority of the monarchs- the ones from east of the mountains- was unknown. It was assumed that they migrated south to sunnier climes. But where, exactly?

Monarch country....

The answer, evidently, was that they went to these forests. Every monarch in the eastern part of North America. That's millions upon millions of butterflies converging on a series of small woodland glades where geographical and climatic factors rendered the temperature, humidity and protection perfect for overwintering. 

The monarch is one of the most recognisable butterflies in the world. It's America's national insect. And it's a superhero amongst butterflies. It can live for over 9 months including hibernation, and a single individual is capable of travelling thousands of miles. The occasional Monarch even shows up in Britain, having been blown across the Atlantic ocean. Monarchs die harder than Bruce Willis.

Monarch larva (full grown)

During summer, they spread out from the Mexican mountain forests across the whole of North America, taking several generations to do so. The large larvae feed exclusively on Milkweed (asclepias sp.) and absorb the poison from the foodplant- hence their warning colouration. Birds do not mess with the monarch. 

Then, just as they've covered the continent, they all turn around and several generations later, arrive back in Mexico ready for hibernation. 

Which is where I found them in February 2001. As I huffed and puffed my way up the mountain, the sun was out and by mid morning it was perfect weather for an overwintering butterfly to wake up, give its wings a stretch and head out on a brief sortie to find food and water. In a few weeks, it would be time for them to move on, but for now they were just preparing for their epic and neverending journey.

As I got nearer to the colony, I started to see them. First in the sky, and then on closer examination, drinking from the tiny streams that criss-crossed their way down the mountainside.

A sky full of monarchs

Drinking at a stream

There had been a frost the night before and, as I turned a corner on the narrow trail, I had my first taste of the true extent of the monarch migration. 

Logging had encroached into the surrounding forest, and one theory goes that the damage done by the loss of the trees protection had started to affect the overwintering butterflies, so that a few on the outskirts of the colony had started to feel the cold. The trail ahead of me was liberally carpeted with dead and dying butterflies, suffering from exposure. 

There were so many that I wondered how the colony could possibly survive the loss of such numbers without being severely depleted. But then, a little further on, the incredible truth started to dawn...

Dead monarch carpet

It's the sound that first lets you know that you're in the kingdom of the monarch. It's a sound so unfamiliar to our ears that it took me a while to understand what it was. It's kind of like the sea breaking on the shore, but it's constant- it doesn't swell and then recede like that sound. It's a whisper, but it's loud enough to overshadow everything.

It's the sound of a million million wings rubbing together all at once. And when you realise what it is, you stop dead in your tracks. I have never heard anything like it, and don't really expect to again.

Now and then, you'll hear a sharp crack, as a branch gives way under the weight of butterflies that it carries. Think about that. A pine tree branch, snapped by weight of butterflies! Surely it would take a stupendous number of insects to pull off a feat like that?

And that's when you start to notice the trees. I mean, really notice them. Notice the bunches of grapes hanging from them. And then, a flash of orange tells you that they aren't grapes at all. In some cases, they aren't really trees at all. They're more like butterfly sculptures of trees. And you're standing right in the middle of one of the biggest migrations on the planet

Bunches of grapes...

Not just trees...

Butterfly sculptures

Everywhere you look, there are butterflies. You think you're seeing a tree, you're actually seeing butterflies. That's not a bush- it's a group of 10,000 butterflies. They're everywhere. And as the sun warms their wings, they rustle them gently and open and close them so that it looks like a thousand tiny pops of orange, exploding all over your vision.

Not a bush...

The sun moves higher, they start to disperse and fly afield in search of nourishment, and the clearings are filled with swirling orange confetti. It's a butterfly snowstorm. 

After a couple of hours with the monarchs, I made my way down the mountain. I was still not adjusted to the altitude, so I hitched a ride on a mule. I was pleased about that, but I can't say that the mule was too keen. I think the camera gear may have been to blame. Heavy things, Nikons. Certainly, it couldn't have been anything to do with my weight. That's my story and I'm sticking to it.

I travelled with Tim Melling and Naturetrek, and it was one of the greatest experiences of my, and I suspect anybody's, life. It took two days for my grin to subside. If I could design a perfect trip, it would be to the sea of Cortez to photograph whales, and then on to mainland Mexico to visit the monarchs. Two weeks of pure natural history wonderment. Brilliant. 

BUTTERFLIES OF BERNWOOD FOREST

I could consider myself a lucky man for many reasons- but one of them would undoubtedly be that down the M40, only 45 minutes from base camp Balham, between the Oxfordshire villages of Oakley and the intriguingly named Horton cum Studley (and trust me, you don't want to be googling that one with the kids around...) lies amazing Bernwood Forest.

Bernwood must surely be one of the premier sites for butterflies in England, and it's a darned fine place to spend a sunny summer's afternoon. It's one of Britain's oldest forests, and thanks to the efforts of the people at BBONT (the Bucks, Berks, Oxon Nature Trust) is beautifully maintained in a butterfly friendly way.

Wandering along the peaceful sun-dappled rides, you get a feeling for how England might have been centuries ago, and an appreciation of just what we may have lost through the ravages of progress. I can get quite misty eyed about it all. Really, I can. I start whistling the theme from Robin Hood (The Richard Greene version, obviously. Not the new fangled one with the bloke from Spooks).

And then, there are the butterflies. There are lots and lots of them. Clouds, even. To see butterflies in this quantity, you would otherwise have to travel to, say, rural mainland europe or the South American rainforest.

But these are British butterflies, which, while not always as big and colourful, are to my mind better- perhaps because of their scarcity, perhaps because of their understated subtlty, or perhaps because I'm whistling the theme from Robin Hood.

So, inspired by the great national butterfly count (courtesy of my M&S, so the ads tell me) I have spent a few hours over the last 2 weeks indulging my inner lepidopterist. I've been into butterflies since childhood, which makes me a true butterfly and bug fan. (I've tried to find a cooler term for this, but all I could come up with was 'Bugger' or 'Butt-head' so, on reflection, i'm sticking with lepidopterist).

In 4 hours over two days at Bernwood, the long suffering Dilly and I counted 21 species. Given that there are only about 58 resident species in Britain, that's a pretty good haul for such a short time. And of course, not all the species are on the wing at the same time, so that total is by no means all of the butterflies found there.

Dilly, armed with a pair of binoculars and a battered copy of the observers book of butterflies, was getting quite enthusiastic at each new species, and I sense that she may too be discovering her inner lepidopterist. Mind you, she was being spoiled. There can't be many people whose third official recorded species is the sublime but seldom seen Purple Emperor. (And yes, it looks as good as it sounds...)

Even I, as an old hand, managed a new 'lifer'- the rather fetching and scarce brown hairstreak, which I'd wanted to see for many years. It's pictured here below, 2nd row down, feeding on Bramble. There are also some of the more common, but no less stunning species pictured; White admiral, comma, ringlet, common blue, large skipper, silver-washed fritillary, small copper, speckled wood and marbled white.

So we have a few weeks of summer left. The common blues are on the wing. Get yourself out into ye olde English countrysyde and count some butterflies. All together now- Robin Hood, Robin Hood, riding through the glen.....