By James Duncan
Learning and Engagement Officer
In this series of blogs I'm going to be exploring the wonderful world of bird song (with some calls thrown in for good measure!) There's surely little more calming to human ears than the annual serenade of spring song. Each day, prior to the sun's appearance above the horizon, birds begin to advertise their presence, demonstrating their strength and ability in song. This serves not only to attract a mate but also to deter rivals. As you wake in the morning, during these times of increased isolation, take a moment to notice the birds who break the morning silence, the Robin, the Blackbird and perhaps the Song Thrush. Enjoy the widening chorus as Wren, Starling, Chaffinch and Dunnock join in. The complexities of bird song may not be easy to get to grips with, but why not take the time to learn? The satisfaction to be gained from identifying birds by song (and calls) really can't be overemphasised - it's truly a window into another world.
8# Greenfinch (Chloris chloris)
Next up, the Greenfinch, an exceedingly attractive and familiar, but declining garden species. Traditionally, the Greenfinch has always been remarkably widespread, its resident distribution across Europe making it one of the most noticeable birds owing to stunning warm green plumage with a flash of yellow - it's certainly the 'greenest' British bird, assuming the non-native Ring-necked Parakeet is excluded. But many may wonder just where the Greenfinches have gone, for the decline in recent years has been catastrophic. Its abundance in the nineteenth century was widely recorded, something that seemed barely to change in the couple of centuries since - it persistently featured in the top ten most numerous garden birds even after the turn of the millennium. However, in 2005 the disease Trichomonosis (caused by the parasite Trichomonas gallinae) leapt into prominence, having a significant impact on the British Greenfinch population by preventing them from being able to feed. Though already known in pigeons and doves as 'canker' and widely recorded in cage birds, it seemed to make the species jump to smaller passerines without difficulty. Transmission typically arises through contaminated food and water, so garden hygiene is particularly important. Though it isn't currently listed as a species of conservation concern, a BTO report in 2017 demonstrated more than a halving of population just in the last decade. Should this continue, the Greenfinch will undoubtedly see itself on the Red-list of highest conservation concern in the next update.
The stout, conical bill of the Greenfinch makes it instantly recognisable as a seed-eater. The wide-scale decrease in the availability of seed on farmland, a once traditional habitat, has seen a much stronger recent association with urban parks and gardens. The sheer size of their heavy bill means they can exploit a variety of food sources and they'll feast happily on all manner of garden provisions. They can be rather dominant and tempestuous, frequently squabbling and chasing other birds away from feeding stations. Though frequently found amongst hedgerows and copses, they display a strong affinity for young conifers. This often sees them at home roosting amongst the controversial cypress hedges (Leyland and Lawson) that are such a prominent feature of our urban environments. Outside of the breeding season Greenfinches can be remarkably gregarious, joining mixed feeding flocks and often roosting communally. They tend to disperse away from their breeding grounds once nesting is complete and some may undertake a partial migration, often within the UK, though additional Scandinavian birds may arrive in autumn to take advantage of our mild winters.
Whilst the 'green' part of the name is rather obvious, it's actually the ubiquitous Chaffinch that's responsible for the naming of the other half, explained in this blog. The word relates to a call made by the Chaffinch, deriving from an old English form of the word 'finch.' Whilst the Greenfinch is certainly a colourful character, it also has a rather charismatic and recognisable song, uttered most typically between March and July, though sometimes even in winter. Greenfinch song is most often delivered from the top of a small tree or bush, though in spring a male may utter a lengthy song whilst undertaking a rather superb and highly flamboyant 'display flight.' The accurately controlled and highly exaggerated wingbeats serve as a useful indicator of his strength and prowess, enhancing his desirability as a suitable mate. If anything, the slow-motion display from the long-winged Greenfinch is more akin to that of a bat, or perhaps even a large butterfly.
Listen to the song in this video -
The mellow song of the Greenfinch provides it with a jolly demeanour, though it isn't always melodic. It has a twittering, liquid quality with a constant stream of rapidly-repeated whistles and trills. Each little phrase is usually always uttered at a consistent pitch, but the song 'see-saws' between phrases of alternate pitch and tone. This should give the song a disjointed feel, but somehow it manages to remain quite organic and not too jarring. The pace of each phrase varies, as the song is often interspersed with more obvious repeated notes - this can give it a surprising amount of complexity. Many of the trills sound almost like 'cartoon laughter' behind clenched teeth or perhaps a child imitating the sound of a toy gun. The song certainly sounds rather jovial and can perhaps be transliterated as something like "jup-jup-jup-jup tuy-tuy-tuy chichichi jurrrrr dordordor twee twee twee juiit." In fact, listen out for the distinctive high-pitched "twee" notes in the extended song below, occurring from 45 seconds in. A key aspect of Greenfinch song is that it actually comes in two different forms, though they're often combined. The second of these occurs from 1 minute 10 seconds in the song below, and is markedly different from the bubbly song described above. Essentially, it's a wheezy sneezing hiss, drawn-out into an extended monosyllabic note that can be described like "dzeeeeuuu." This aspect of the song is delivered more regularly in the breeding season and is usually repeated with long pauses. The full song can either be relatively short, with distinct gaps or lengthy and frantic with greater diversity, though this is typically performed by highly agitated males.
Listen to an extended version of the song below -
The predominant call of the Greenfinch, also given in flight, is recognisable as a shared feature from the song. It comprises the same diagnostic musical notes repeated in an extremely rapid series to create 'rippling' trills. These have a delicate 'quivering' quality, sounding almost if the bird is being shaken whilst attempting to perform. They may be transliterated as something like "jup-up-up-up-up-up" or "dji-dji-dji-dji-dji-dji." This may sometimes be slowed right down (particularly in flight) and reduced to just a single or double noted "jupp, jup" which is harder and more forceful than the Chaffinch equivalent.
Listen to this call below -
Another call given by the Greenfinch that may very well feature in the song is the common alarm call, transliterated as "djuwee" where the second half of the note is delivered distinctly with a forcible upwards-inflection. It has a 'bounce-like' quality and always seems to suggest the bird has had a rather nasty shock right in the middle of the note.
Listen to this call below -