This time of the year sees the arrival of recently fledged birds in gardens all over the UK.
Many of them will have followed their parents visiting gardens to take advantage of food sources available to them, both natural (worms etc) and supplementary such as bird seed, fatballs, and other tasty morsels. Some of the young birds most likely to be seen in a typical garden setting include the robin, blue tit, great tit, chaffinch, blackbird and starling. Many of these young birds will have a plumage that differs greatly from the adults.
The juvenile robin lacks the red breast of the adult, meaning they can sometimes be difficult to identify when first leaving the nest. Their usual red breast is speckled golden brown, gradually turning to red with their first ‘partial’ moult. As with most young birds, they will continue to be fed by the adults for several weeks after leaving the nest.
Another juvenile bird which looks different to the adult is the blackbird; they have a rich brown speckled plumage, and a dark bill, in contrast to the bright yellow bill of an adult. Blackbirds will often leave the nest before they can fly, leaving them vulnerable to predation whilst they hop in and around shrubs. However, you should resist the temptation to pick them up or move them. The adult parents usually know precisely where they are; just as well as they continue to feed them for several weeks.
Members of the corvid family are also feeding their young. Magpies, jackdaws, jays and crows are busy providing food to their young chicks. Although many people find it upsetting to watch, it is natural behaviour for magpies, jays and other predators such as stoats, foxes, and squirrels to occasionally raid the nests of smaller birds, taking either eggs or chicks. Fortunately nature compensates for this and many other losses by enabling passerines to have large clutches. From a clutch of say 10-12 blue tit eggs perhaps only one or two will survive, many having been killed by predators, or by striking windows, etc.
Although there is plenty of bird activity in the garden during spring and early summer – with adult birds busying themselves taking care of their broods, and the young birds finding their way around, as mid/late summer arrives, it can become strangely quiet in the garden. Why? The moult, which is the process of replacing worn feathers with new ones. After a busy nesting season, adults are beginning to look quite bedraggled. They will keep a low profile during this process, especially as they lose their primary (flight) feathers, meaning they aren’t as efficient at flying as they usually are and they could be more vulnerable to predation during this time. The moulting cycle can vary depending on the species of bird. For example a small bird such as a blue tit could complete the moult within about six weeks, whereas the process for a bird of prey can be spread out over many months.
The end result of the moult is a bird ideally in tip top condition, ready to take on the challenges of winter, and then repeating the whole cycle again next year.