AS WE MOVE into late summer and autumn, plants across the countryside will be producing fruits and seeds.

Some of the most prolific are in the Asteraceae family – that’s dandelions, daisies and thistles to you and me. This is obviously good news for the plants in question, but it also benefits assorted animals that feed on these seeds.

Thistle seeds are a favourite food for goldfinches, and plants may be visited by large flocks of these birds in late summer.

East Lothian Courier:

The goldfinch (pictured above) is a beautiful little bird, with a lilting liquid twittering song. Adult birds are easily identified by the red, white and black colouring on the face and head. This is absent in juveniles, but goldfinches of all ages share striking black and gold-yellow wing markings, which can be clearly seen in flight. The beak is relatively long and is well adapted for feeding on the seeds of thistle and teasels, although goldfinches will also take insects, especially during the breeding season.

For those of you interested in scientific names (and who isn’t?), the goldfinch is termed Carduelis carduelis, reflecting its main food source – Carduus being Latin for thistle.

Goldfinch numbers declined seriously during the 1970s and ‘80s, but have recovered significantly since then and continue to rise, which is nice. This is thought to be largely down to an increase in these birds using garden feeders, particularly those filled with niger and sunflower seeds.

If the goldfinch has been a recent success in terms of its numbers increasing, then the same cannot be said for another finch. The greenfinch (pictured below) used to be a common sight, both in gardens and the wider countryside, although not any more.

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It’s a much chunkier bird than the goldfinch and, unsurprisingly, has a distinct greenish tinge to its plumage. Juveniles and females are less colourful than males, being a bit more grey-brown, but all show yellow on the wings and tail.

They produce a range of sounds, including a trilling, twittering song and a drawn out nasal wheeze, brilliantly described as a “condescending sneer”.

As mentioned, greenfinches are much less common now. This is due to a disease called trichomonosis, caused by a parasite spread through food and especially water. The condition has been seen in pigeons and doves for a long time (in these birds it’s known as ‘canker’), but started appearing in songbird populations in about 2005.

Whilst several species are vulnerable, the greenfinch has been hardest hit, with the UK population declining by about 60 per cent in the last 15 years.

Some of the spread of the disease may be down to finches having shared tables, feeders and baths with other infected birds. This is a reminder to always maintain good hygiene around your bird feeders – keep them clean and change the water in bird baths regularly.

There is some evidence that the decline in greenfinch numbers may be slowing, although this evidence is very slight and extremely anecdotal.

If that is the case, then it may indicate a certain level of immunity or resistance building up within the population, which would be great news.