The boat is called the Golden Mean, but there was little moderation that day: the first day of June, the first of 30 Days Wild that the family, as encouraged by the Wildlife Trusts, will try and follow: at least one wild moment every single day of a wild month. It is the start of a month of excess.

Our friends the Harrisons live on the Golden Mean, and they invited us to their home for a gentle chug down the Waveney, the river that divides – or unites – Norfolk and Suffolk. It was there we celebrated the new month. Not a bad way to seek nature, sitting at the bow, away from the thrum of the engine, binoculars to one side and a cold beer at the other. Reed warblers and reed buntings sounded a perpetual fanfare as we passed.

It was on the way back that it happened. I was suddenly aware of what looked like a huge brown falcon, going like the clappers along the river, overtaking the boat and then making a sharp ascent. In an instant the mystery was solved, for she flew straight to a male marsh harrier that was waiting for her in the sky with wings outstretched.

Harriers mostly fly with slow beats mixed with long and slightly wobbly glides: here was a harrier filled with sudden speed and purpose. The reason for this was revealed at once, for in this passionate meeting in the sky – like the meeting of two long-separated lovers – she inverted, the male let fall a dark item of food and she caught it in her talons, doing so with the greatest nonchalance. She then dropped to devour while the male cruised away in search of more.

This, then, was the famous marsh harrier food-pass. Why do they do it? It seemed obvious from the deck of the Godden Mean: because when you perform it right, you feel really rather fabulous: and what’s more, fabulous in your togetherness. The manoeuvre requires top-notch flying skills and finely-judged coordination. It can only come from extensive practice. It is a great bravura celebration of being a marsh harrier, sure, but more than that, it is a celebration of being two marsh harriers together, both involved in the glorious task of making more marsh harriers. Here was a sky filled with passion.