Plumage damages

For a continuous flyer like a swift, complete and undamaged plumage is just as important as an intact muscular system. Plumage damage of swifts can have various causes:


Damage due to trauma
Accidents and awkward landings can lead to breakage or loss of wing and tail feathers. Also grazing wounds can occur with extensive feather loss, e.g. due to high voltage cables. Attacks by predators (ravens, raptors, cats...) often finish, if the swift survives the attack, with feathers ripped out and trauma to soft tissue. Puncture wounds in the wing area commonly affect the feathers of the metacarpus (external part of the wing structure).


Mechanical damage to plumage
This damage is mostly observed for incorrect keeping and accommodation of swifts by humans. Swifts which are kept in a wire cage or in excessively confined conditions can bend and crack flight and tail feathers. Similar problems can arise if a swift flies into a building, e.g. in roof spaces, and then tries to escape. Also bent, holed or twisted flight feathers can occur if a swift gets tangled up in thread-like material, which can easily happen in a nesting place: sparrows carry lots of nest material, including threads, into their nesting places, which can lead to disaster for a swift which later uses the nest.
Inappropriate and unhygienic conditions of swift “patients” while in human care frequently cause such dirty, filth-encrusted plumage that the bird is no longer capable of surviving in the wild. Similar things can happen for thoughtless, amateurish feeding, when the swift can be covered and encrusted from head to foot by a sort of “food slop”.


Plumage damage due to incorrect feeding
For wrong feeding, which is not correct for this species, severe plumage damage is regularly observed in young swifts, and can be summarised in two classes:

1)    Loss of primary wing feathers with blood quills
2)    Shaft (central part of feather, rachis) and barb (the lighter part attached to the shaft) defects of various degrees

 In parallel, the body (down) feathers are also more or less widely damaged, and they become dull, blotchy, frayed, and shaggy, so that they lose their natural insulating properties, that protect the bird from wet and cold.

1) Loss of wing feathers with blood quills
Various primary feathers can be affected differently. The damage can be symmetric or asymmetric. Sometimes only one wing feather of incorrectly fed young swifts fall out on both sides, but much more common is the loss of five or six feathers per side. Nearly always the affected feathers stagnate during growth, and the bird “stays short”. The time interval from the stagnation of growth to dropping the first feather varies in length, and sometimes is only a few days, sometimes a few weeks. It is noticeable on the feather which has fallen out that the shaft which is not fully grown is short and often deformed. A stable strong shaft is not formed. Tail feathers are generally not affected, but they often have defects, such as cracks on the shaft or lesions, which can be described as “hunger streaks”.

It is not always possible to establish a causal relation to the kind and point in time of the origin of the illness. In a few cases however, there is some experience: feeding mince meat nearly always leads after ca. 8-10 days to loss by the patient of several primary wing feathers. The birds are usually ca. 4-5 weeks old at this point.
Feeding with oat flakes, if the young swift survives it, regularly leads after 4 weeks to teh loss of large primary wing feathers. This happens even if the bird is fed oat flakes only once!
The age of the young swift at the time it is incorrectly fed seems to be important. For groups of three siblings from the same brood, which have only a difference in age of only a single day, it has been observed several times that the three nestlings develop different types of plumage damage after incorrect feeding. Generally, different types of plumage damage appear on wrong feeding, depending on the age of the birds.

2) Feather shaft and barb damage of various degrees
To this kind of damage belong cracks, weak points and deformities of the shaft which do not resist under load but crack or break. Damage to the barbs is manifested as transparent, missing or incomplete areas of plumage, which break up the continuity of the feather and reduce its performance. Because this is mostly not limited to a single feather, but to several, or in the worst case, the whole group of primary feathers, the flight ability of the swift can be reduced to nothing. Shaft and barb damage is mostly seen not just in the primary flight feathers, but also at the same time in the tail feathers.
Not uncommonly, especially with mealworm feeding, it comes to a persistence in the development of the calamus and the bird is unable to clean itself properly because a sticky, rubbery residue remains. The barbs cannot be separated. In the worst case, they can be damaged.

 Plumage damage due to stress
It is not rare to observe nestling swifts who have been exposed to increased stress. This often regards foundlings who are passed from hand to hand by excited finders, exposed to noise and confusion by children playing and running around. During growth the result is stagnation and loss of primary feathers of this inappropriate treatment of the foundling.

Other plumage damage
For several years, a previously unknown type of primary flight feather damage to young swifts has been observed, the so-called Paper-Shaft-Syndrome (PSS). The cause of PSS has been suggested to be a lack of protein during the nestling phase. Widespread PSS was first documented in the summer of 2003. The primary and secondary feathers are affected.

Paper-thin feather shafts, pressed together at the bases of the feathers are pathogonomic. The problem is difficult to discover, because at first glance it is not as obvious as other plumage damage. Apparently the young swifts are completely free of injury. Only when one examines each shaft carefully under the covering feathers is the extent to the damage clear. The function and stability of the usually three-dimensional shaft as a super light, tubular construction is completely missing, and the squashed feather shaft cracks under the slightest pressure. The inner primary and secondary feathers are always affected, and so the problem is particularly serious, because the bird’s ability to fly is removed. The shafts of the large primary feathers (10 to 7 or 6) are not pressed together, but they show weak points at about 1-2 cm above the base. The tail feathers are frequently, but not always, affected by PSS.

Measures against plumage damages

Primary feather damage that can be cured includes:
a) incorrect feeding or stress induced flight feather loss which have to push out again
b) flight or tail feather loss due to trauma or mechanical causes, for which normal re-growth is expected,
c) broken, cut, cracked or otherwise damaged flight and tail feathers, which can be replaced by falconry methods of “imping”,
d) damaged flight and tail feathers, which cannot be replaced by “imping”, but must be removed under general anesthetic to allow regrowth.

re a) and b): the affected swift remains in human care, until the missing feathers re-grow. If the feathers have fallen out, they mostly re-grow quite quickly, in 4-5 weeks. After a trauma, it can last several weeks until the new feathers begin to grow.

Complications are common. Young swifts, who have to remain for longer than the normal nesting time in captivity, and adult swifts are often very agitated so much so that they can bloody their growing feathers, trying to escape. This can also lead to blood losses that are life endangering. A damaged shaft that is cracked or even broken dies off. It must then, when it is completely dried out (after 8-10 days) be removed carefully so that a new feather can grow. The problem can lead to a vicious circle, in which in the worst case, the feather follicle, after many attempts to produce a feather, is completely exhausted and produces only a “cripple feather” or nothing at all.

If primary feathers are badly knocked or removed, it can also lead to significant complications for re-growth. Often the plumage is heavily damaged, sometimes irreversibly. No new feather grows because the follicle is damaged. A swift can tolerate a single missing primary feather, but no more, and euthanasia of the bird is then unavoidable. First the bird should be anesthetised and a thorough examination of the feather follicle carried out. Often the feather system blocked deep down by detritus, dried blood or broken feathers. After removal, new feathers can grow.

to c): For intact feather shafts, broken flight or tail feathers can be “imped”. Imping is a method practised as long ago as the Middle Ages in falconry, to repair broken main feathers (HEIDENREICH, 1995). One used a square metal needle (imping needle) to connect an undamaged feather to the shaft of a broken one. HEIDENREICH (1995) described other more recent methods of imping using glass fibre and bamboo, or preferably the shaft of another feather, as a similar material that showed the best properties. Imping of swifts, the last hope for many apparently hopeless cases of plumage damage, will be described fully in the next chapter.