Much as I love the Cornish rock pools, there are times – throughout the year – when the conditions are grim. According to the forecast, today is going to be one of those days. I have reluctantly cancelled a meet-up with Junior’s friends because the charts show the sort of gales and lashing rain that have most little kiddies shivering before they even reach the pools.

I don’t want to make rockpooling a traumatic experience for other people’s children, but I don’t think Junior’s aware that staying in is an option. He’s so well trained to enjoy the misery that at 10am he’s merrily pulling on waterproofs and wellies and grabbing a bucket. We’re off to ‘the gully’ and no amount of buffeting winds or ominous clouds are going to stop him.

We are climbing across the rocks from Plaidy beach towards our favourite spot when hail starts ricocheting off our buckets. We keep our heads down, turning our attention to the variety of colours in the pebbles. Junior crams his pockets with his favourites, the extra ballast helping to keep him upright against the howling wind.

The rocky gully is a little more sheltered if you crouch low enough. I adopt a sumo stance and waddle around checking rocks. Every single one conceals groups of worm pipefish, their bodies tangled together.

I’m taking photos of a blob, which is a stalked jellyfish marooned above the water-line by the big tide, when Junior announces it’s time to go ‘mountaineering’.

I feign deafness for a few more minutes, looking at crabs and urchins, but he’s persistent and soon I’m scrambling up a slope in the rock and attempting to follow him as he leaps across the sharp ridges and shoots down the steep seaweed-covered slopes to the next gully.

The low pressure and large waves are keeping the tide from falling as far as it might otherwise, so I’m wading to the top of my wellies when I find this sea slug, a Limacia clavigera. On the rock it’s formless, so I pop it in some water to take photos.

Junior returns from his latest expedition across the rocks telling me there’s ‘something I have to see.’ Inevitably, his find involves more climbing and some perilous leaps, which are a challenge in my clunky wellies.

The narrow gap in some huge rocks he’s discovered looks promising and Junior assures me it’s the most sheltered place on the beach. I suspect this might be a good spot for Devonshire cup corals and some other species which like strong currents. I won’t find out today though. The waves are exploding through the gap and the water in front of me is chest-deep.

We explore the pools. A rockling is splashing among the kelp and on the overhang, an Arctic cowrie is grazing. The damp weather suits shore creatures just fine.

The tide is due to turn so we start to gather up our things. When it starts to hail once more, I abandon taking photos of a beautifully decorated little spider crab and we clamber up the narrow cliff path.

As the downpour slows, we take a breather and look back over the rocks we’ve explored. The beach is completely empty, except for a pair of calling herons flying over. Somewhere a lone oystercatcher is trilling away. Despite his coat being wet enough to wring out (and I suspect his socks are too…) Junior declares the expedition a success.

I don’t know where he gets it from…