Greenfinches are scarce visitors to our garden nowadays, which is a real loss because they always bring so much colour with their green plumage and bright yellow flashes on wing edges and tail.

When I was growing up in Edinburgh in the 1970s, greenfinches were amongst the commonest visitors to our garden peanut feeder; bold and brassy and always quick to shoo away other birds that came too close. In the early 1990s, I recall seeing a huge flock of around 300 greenfinches roaming farmland in Buchan in north-east Scotland.

But they certainly do not seem to be nearly so common now. I suspect the reason for this scarcity is down to avian trichomoniasis disease, which has taken its toll on the population over the last decade or so. It is a known affliction of pigeons and doves but which now seems to have made a transmission jump to finches.

Birds suffering from the disease often look lethargic and have trouble in feeding and breathing. In some parts of the country, greenfinch numbers have dropped by a third within a year of the disease emerging.

Ironically, bird feeding may have contributed to the spread of the disease due to greenfinches coming into close contact with each other around garden bird tables.

It is all very sad stuff, but perhaps also something that will sort itself out in time. Nature has a habit of doing that.