GARDEN BIRDS
WHERE are our garden birds in August?
Our garden bird feeders are very busy during winter as birds seek out food to assure their winter survival. During spring we enjoy their early morning orchestral chorus as the breeding season gets under way. This cacophony of sound is coupled with regular visits to our feeders; initially this is to ensure that they are in top breeding condition. Later on we are treated to the sights of the parent birds scurrying back and forth from our gardens to their nests satisfying the voracious appetites of their rapidly growing young. If we are lucky in late spring and early summer, we may experience the ultimate reward for garden bird feeding which is witnessing fledglings undertaking their often very clumsy looking “maiden flights”.
During mid-summer the numbers of birds visiting our gardens and feeders seems to dramatically drop off. Have they migrated, been preyed upon or have they become sick and ill? Fortunately nothing as dramatic as that has actually happened. The birds are still around but they tend to be more secretive as they prepare for autumn and winter. Feathers, which birds rely on for flight and warmth, are not indestructible and with time they become tatty, discoloured and weakened. These have to be replaced – a process known as moulting. The breeding season can have a dramatic impact on the well-being of adult birds. Most of us will have seen ragged-looking Blue and Great Tits; a result of their day after day feeding sorties, in and out of the nest hole, where each chick can eat up to 100 caterpillars a day. The adults will need to find as many as 1,000 caterpillars a day for a brood of 10!
The month of August is a prime time for birds to undergo the potentially dangerous process of replacing some, or all of their feathers; it is a very energy-intensive process and makes them more vulnerable to predation. During mid-summer there is plenty of cover for them to hide away, along with an abundance of protein-rich food. It is also warm so they are not so reliant on all of their feathers for warmth. During their moult the birds do not lose all of their feathers at once – this would make them less mobile and vulnerable to the cold and predators. Similar to our own hair, feathers grow from follicles in the birds’ skins and the newly developing feathers push out the old ones.
This process occurs in a defined and gradual sequence across birds’ bodies to ensure that there are no bald patches. The extent of moult varies across species, their age and time of year with most birds undergoing a complete moult once per year although this can be over two or three separate moult periods. These moulting periods are typically before and after breeding. Most garden birds undergo their moult within a period of 6 to 8 weeks, after which they can begin to build up their energy reserves for the UK winter or for their migration flights to their wintering grounds. Migrating birds tend to carry out their moults faster than resident species to ensure that post breeding they can be in top condition for their arduous migration flight as quick as possible. It is recommended that you continue to feed birds year round to meet the varying demands of the birds over the seasons.