Swallowtail Butterflies in Norfolk: Two Trips and a Soggy Poster

By Carol Leather

The British Swallowtail is our largest and rarest butterfly: pale lemon-yellow wings with black veins, red-orange spots, and a flash of blue. It exists in the wild only in the fens and broads of Norfolk.

I'd wanted to see one for years. Their only UK stronghold sounds remote and specialist until you check the map and realise it's a manageable weekend from most of England. So my husband and I planned an escape, with my hopes pinned entirely on finding this single, magnificent butterfly.

It took two trips to get there. The first taught me more than the second.

Trip One: Rain and a Soggy Poster

Our first trip, at the end of May, was a washout.

As soon as we arrived at Strumpshaw Fen, the leaden grey skies released a torrent of water. The volunteer in the visitor centre gave us a sympathetic look. "You won't see them today," he said. "They hate the rain and wind."

He was right. We walked the reserve in the downpour, saw no butterflies at all, and came back soaked.

The only Swallowtail we saw that year was on a large soggy poster.

The only Swallowtail we saw in 2021

A rather wet Strumpshaw Fen map

The Day Belonged to the Marsh Harriers Instead

As the rain eased we looked up at the wide fenland sky. Dots in the distance became quartering Marsh Harriers, regularly dropping down into the reeds.

And as if that wasn't enough, the dead tree in front of us was apparently the ideal perch for rearranging feathers. So close, it was easy to see their massive yellow feet and the female's cream-coloured head.

It wasn't the weekend we'd planned. But those harrier sightings were genuinely special, and I might have walked straight past them if I'd been staring at wildflowers waiting for a butterfly.

It's a habit I've kept ever since. Whatever you've come to see, leave room to notice what's actually there.

Trip Two: Back in Sunshine

A year later, we were back in Norfolk for a long weekend in June. This time, the weather was perfect: hot, sunny, and still.

If you've never planned a wildlife trip before, the secret isn't expertise. It's a weekend, decent weather, and modest expectations. We had all three.

We started at Strumpshaw Fen again, and this time I was glad I'd learned to pack for the terrain, not just the forecast. My waterproof boots felt like a badge of experience earned from the previous year's soaking.

We saw green-eyed Norfolk Hawker dragonflies resting on reeds, a species found almost nowhere else in the UK.

We watched a Great Crested Grebe with three tiny babies on its back, a sight that always makes me smile. I once spent a whole breeding season with a pair of these birds at Barnwell, watching the courtship dance, the floating nest, and chicks riding their parents' backs from hatching to independence.

After an hour sitting in a hide, watching the antics of ducks and coots, my attention was pulled towards the reeds on the far bank.

What had I seen? Just the breeze? Wait, something ginger was behind them. Then a head with a big black nose peered out.

My first Chinese Water Deer, tusks and teddy-bear ears

And then, as we walked past the historic Doctor's House, it happened.

Two Swallowtails in the Garden

Not with a grand announcement, but as a quiet flutter in the dappled sunshine among the garden flowers. Two of them.

I felt my breath catch.

The Swallowtail's wings weren't just yellow. They were the colour of pale lemon silk, so thin the sunlight seemed to shine right through them.

I blinked. They were still there, but then flew in different directions. My eyes couldn't keep up. Where had they gone? Ah there you are, my beauty.

Once I stopped gawping, I remembered the camera hanging round my neck and reacted, grabbing a few record shots as evidence.

Hickling Broad and a Better Photo

The next day, we visited Hickling Broad Nature Reserve, and it was here that the Swallowtails gave us something even better.

There were just two other vehicles in the car park when we arrived. We slipped through the open gate, wondering if that was allowed, and set off before we had second thoughts.

Within minutes a Swallowtail whizzed across the path.

The first human we met was just leaving the thatched bird hide as we arrived. She mentioned seeing the butterflies nearby and offered to show us where.

We retraced our steps. The lady stopped, pointing to the greenery beside the path. Perched atop a flower was a Swallowtail, its wings catching the sunlight.

Side view: the red spots and blue patches catch the light

I realised it wasn't alone.

They were all along the pathway. No need to rush. I relaxed and started thinking through the photograph instead of just snapping away.

Did I want everything sharp, or just the butterfly? I tried a setting that kept everything in focus, including the background clutter. No, that didn't work. So I tried the opposite, letting the background fall away into a soft wash of colour, and suddenly the Swallowtail was the only thing your eye landed on.

A Swallowtail in an interesting pose

And again, Norfolk gave us more than the butterflies. A Willow Warbler singing from a treetop. An otter we spotted on the final day. The Broads keep giving you reasons to look up.

If You're Planning a Swallowtail Trip

From two trips and a soggy poster, here's what I'd pass on.

• When to go. Late May to mid-July. June is usually the sweet spot.
• Where to go. Strumpshaw Fen (RSPB) and Hickling Broad (Norfolk Wildlife Trust) are both reliable. From our experience, Hickling gave us closer, longer sightings.
• Weather matters enormously. Swallowtails need sun and still air. If it's raining or blowing, they won't fly. Check the forecast and be prepared to adjust your plans, or your dates.
• Go early. Fewer people, calmer conditions, and the butterflies are often most active in warm morning sun.
• Pack for the terrain. Waterproof boots even in summer. The fens are wet underfoot. I learned this the hard way.
• Be a quiet visitor. Swallowtails will land near you if you stay still and wait. Don't chase them around for a closer shot. The patient photographer almost always gets the better picture, and the butterfly stays calm.
• Look beyond the butterfly. Both reserves are packed with other wildlife. Norfolk Hawker dragonflies, Marsh Harriers, Chinese Water Deer. The Swallowtail is the headline act, but the supporting cast is wonderful.

Further Reading

I've spent over 30 years walking and photographing UK wildlife, with work featured in Canon EOS Magazine and a Wildlife Trusts calendar. I still learn something new on most outings.

This site is my field notebook full of photo tips, help on identifying what you see, and how to decide where to walk.