AS a wildlife artist, I receive countless commissions to paint a favourite mammal or bird, but I am very rarely given instructions as to the landscape in the background.

But last year I asked to paint oystercatchers on the beach at Craster Harbour in Northumberland. My client, the children’s author, David Brazier, wanted the picture to be an engagement gift and had chosen Craster harbour since it is a favourite holiday destination for himself and his partner.

As soon as I could I drove up to Craster Harbour to gather reference material for the new commission.

I have only painted oystercatchers once before so I was going to need to get to know them better if I was going to get my painting right.

The trouble was I had no clear idea whether I was going to actually see any oystercatchers when I got there.

I decided to set off very early one morning in order to be there at low tide when I hoped that if they were going to be any at all they might be feeding.

It was a chilly overcast day and as I got out of my car I was met with a brisk wind. I grabbed my binoculars and scanned the exposed beach, but before I even had time to focus my lenses I heard the unmistakable, piping call of an oystercatcher.

On the beach, I picked out six; probing the sand with long, orange beaks. My priority was to photograph the birds and then think about the background later.

So I grabbed my cameras and tripod and slowly approached the group as they rushed back and forth on the sand, their movements in sync with each wave.

An oystercatchers’ day revolves with the tides. It feeds on the cockles, mussels, crabs and worms exposed when the tide is out. Then it rests when the tide comes in.

Once I was close enough, I sat quietly to watch. Oystercatchers have striking black and white plumage and long orange beaks which they use to skewer open mussels - and oysters.

When running, their legs move so fast they look like clockwork toys, comically jogging along the beach, and for much of the time they are very noisy and argumentative.

I watched as pairs defended small patches of beach from one another. They would arch their backs, lower their bright beaks and let out an angry peep.

I could see their appeal - and also the draw of Craster, which is an undoubtedly a beautiful bit of coastline. No wonder David wanted to capture the memory of being here.

I too was mesmerised and it wasn’t until the tide turned and the waves were lapping at my feet that I realised I had snapped more than 1,500 photographs.

With the tide now in, the birds flew down the coast and out of sight. I followed to where they had joined a flock of 50 birds all roosting on the rocks.

They stood facing the wind, each one propped up on one leg with its beak tucked under its wing. Occasionally a bird would lift its head briefly to preen, and then resume its one-legged stance to rest.

Moving among them were turnstones, busily rolling seaweed and stones to look for food underneath, glistening flocks of golden plovers wheeling over the sea, and even eider ducks.

I watched entranced for a number of hours before remembering that David’s proposal was going to be at sunset and that I still needed to gather reference material at the harbour.

It had been overcast all day, but now, as if on cue, the clouds cleared and I took my final photographs as the last rays of sun glinted over the deep blue water.

I hastened back to the spot where I knew David intended to propose. Not only did I want to soak up a bit of the atmosphere as the sun lowered in the sky, but I also needed to know exactly where it would set if my painting was going to be accurate.

Back in my studio, I chose to position a pair of oystercatchers on lichen-covered rocks, one lifting an orange leg as if in acceptance of an engagement.

I also painted a boat, tied up in the harbour, and on this I inscribed the date, and time, 11.11.11, of David’s proposal.

David was delighted with this, since he had deliberately chosen the day due to his deep spiritual faith in the significance of the number 11. And in fact he was so pleased he also asked that the boat be named after his fiancé’s late mother, Aileen.

It is very unusual for me to have included so much symbolism in my artwork, but in fact I found it a heartening to be part of such a meaningful story.