Swallowtail Butterflies in Norfolk: Two Trips and a Soggy Poster

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 is a manageable weekend trip from our home in Cambridgeshire, 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 Marsh Harriers Didn't Mind

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 their 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.

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.

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.

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.

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.

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 closing down the aperture so everything was in focus. No, that didn’t work. So I opened it instead. The background blurred into a wash of colour, and the Swallowtail was the star.

It was also here I learned that Norfolk isn't just about the butterflies. A Willow Warbler singing from a treetop, an otter we spotted on the final day — these were all things I might have missed if I'd been staring at wildflowers the whole time.

If You're Planning a Swallowtail Trip

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

• When: Late May to mid-July. June is usually the sweet spot.
• Where: Strumpshaw Fen (RSPB) and Hickling Broad (Norfolk Wildlife Trust) are both good. 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.
• 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.
• 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.

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