On the south coast of the Isle of Man there exists a field so impossibly teeming with birds that I don’t know where to begin. I was last there on Christmas Day – an odd day to go birding perhaps, but not here. The island’s annual Bird Race, a collective effort to find as many species as possible, runs between Christmas and the new year. In 2022 we set a record: 121 species, three of which were found in this field and nowhere else. So what’s this field got that makes it so popular for birds? Weeds, glorious weeds – which modern society tells us to hate. Aren’t they wildflowers too? The field is a throwback to 70 years ago, to the heyday of mixed farming, when every farm had an acre of vegetables – and lots of weeds. Today I make a visit. A flock of twite is busy doing the rounds. To listen to their soft, excited chatter is one of the great joys of birding. And this is the only place where you can hear them on the island this winter. They are joined by skylark, greenfinch, linnet and lesser redpoll. In five minutes I see more reed bunting than I saw throughout 2022. Yet there is something altogether more rewarding hidden here. I am hoping to see a tree sparrow. On our island, this overlooked yet handsome bird is our most threatened, thanks to our hatred of weeds. There is a very real chance that we will lose them, and soon. This weedy field of veg is supporting two tree sparrows this winter. Such is their perilous state, they caused a small twitch on Christmas Day. Today I catch only the briefest glimpse of one. Content enough, I pop into the farm shop, thank Mrs Gawne for her conservation efforts and compliment her on her weeds. If we’re going to save tree sparrows, we must support farmers to provide a lot more fields like this. Economics have forced our farmers to specialise and to hate weeds, and we are losing biodiversity as a result. On our island we have 90,000 acres of grazing, yet just 45 acres of veg. This explains why most farmland birds have graphs going the wrong way, and why there’s one bird I did not see today. Once common, we recently lost our yellowhammer. They would have liked these weeds.