Stratos feathering
Stratos are sapiential Artes, and one of their main traits is the presence of bird-like feathers. These are complex integumentary structures made of beta-keratin (or alpha-keratin in Zephyrs), and display a more resilient structure and faster growth compared to a bird's. Feathers cover sections of the Stratos body through growth in organized follicles. They accomplish an important role in flight (for Cyclones and Whirlwinds), thermal regulation, waterproofing, and career. Stratos are all sterile, so unlike birds, they present no plumage-based sexual dimorphism or nuptial moults.
Moulting
Stratos go through flight feather moulting once per year. The timing of the moult varies between individuals, and it's a trait taken into account when assigning a Stratos to a job. For example, Wardens in a team will not share moulting seasons, in order to guarantee always having active Wardens and allow the moulting ones to rest.
Standard moult leave lasts three weeks, and the Stratos is only allowed back on duty after getting cleared from a medical exam. Moult leave is granted once the Stratos sheds a flight feather or is medically deemed unable to serve.
After a moult, Stratos are responsible for cleaning up their shed feathers. These may be donated for usage in bedding and winter clothing, or disposed through specialized biodegradation facilities. Improper feather disposal may incur a fine and a decrease in Trust Rank.
Moult process
The total length of a moult depends on available resources, plumage coverage, and individual traits. On average, for a Whirlwind with complete nutrition and rest, a full moult can take a month and a half, with the critical* phase lasting two to three weeks.
Moulting order
- Head and neck
- Down the back and mantle
- Across chest and torso
- Between the legs and thighs
- Wings and tail feathers
Health considerations
The Stratos will be lethargic and irritable, and being vulnerable may even cause aggressivity. Hormonal changes may cause gastrointestinal problems. It's important to keep moulting Stratos well-fed during this time. Due to the high amount of energy used, Stratos may sleep much longer than usual (18-20 hours during the critical phase is normal). A high protein diet is paramount, as feathers are made up of ~80% protein. Frequent baths, high humidity or water misting may help to lower the discomfort of itchiness.
Giving the Stratos leave from their responsibilities is obligatory. The lack of energy will cause bad performance, and stress can lead to poor feather development, which cannot be corrected until the next moult or by using prosthetics.
Wings and tails
Stratos present a diverse variety of wing types. Only the flighted Stratos species (Cyclones and Whirlwinds) present a standardized wing classification system, and they are often a critical consideration when seeking a job.
| Flighted Stratos wing types | |
|---|---|
| Soaring wings | High speed wings |
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| Broad wings with slotted primary feathers, which help reduce the lift-induced drag but maintaining a somewhat slender tip. Mostly used for soaring in thermals with low energy expenditure. Stratos with soaring wings tend to be of average height and weight. These are the most common wings seen in Stratos as a whole, being a balanced shape for endurance and agility. | Short wings with a high aspect ratio, slender tip, and flatter profile, resulting in energetically expensive high speed. Stratos with high speed wings tend to be of shorter height, allowing them to sustain high g's with more ease. They also lean into being more muscular than average, as high speeds require great exertion. More common in Cyclones than in Whirlwinds. |
| Coastal wings | Agility wings |
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| Long wings with a high aspect ratio, being narrow and pointy with no feather slotting. Used mostly for low speed soaring, taking advantage of wind shears above the ocean. The slower speeds allow for fine movement, and its reliance on wind makes it low-energy but dependent on weather. These are the most common wings seen in coastal Stratos—hence the name. | Short wings with a low aspect ratio, with a roundish end and slotted feathers. Mostly used for very tight maneuvering, but aren't suited for long distance flight. Agility winged Stratos tend to be short, and are most common in urban-dwelling civilians. Pure elliptical wings are the most uncommon wing shape found between Stratos; they are more commonly mixed with soaring wings. |
| Thermal wings | |
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| Long boxy wings with deep slots. This space between the primaries reduces drag and wingtip vortices. They are mostly found on inland Stratos, taking advantage of thermals (vertical columns of warm air). They represent a more extreme build of the soaring wings, featuring flight with minimal flapping, very high endurance, but poor maneuvering. Most common in Whirlwinds than in Cyclones. Stratos with thermal wings tend to be on the taller side. | |
Preening
Preening is a behaviour found in Stratos in order to maintain their feathers. It involves the straightening of feathers, interlocking stray barbules, cleaning plumage from dust or debris, plucking loose down or freeing pin feathers, and checking for parasites. Preening is a paramount activity, as plumage is critical to Stratos. Not only for flight, but to maintain insulation, waterproofing and appeal. Additionally, it comes with an important social function, as most Stratos will preen in pairs or even groups.
To keep feathers in good condition, they get covered by either oil or dust during the preening process. This helps to extend the life of the feather, supporting the microscopic structures that create the waterproof barrier. All Stratos have oil glands in the ventral base of the wing. It secretes oil composed of water, fatty acids, waxes, and symbiotic bacteria. Proper bacterial flora in the oil is important, as it helps to repel feather-degrading bacteria in the plumage.
Due to the extensive population of Stratos in contemporary Tarrukar, there's a thriving market of preening oils, including varieties with scents, tints, and different finishing looks (gloss, sculpting, etc). The growth in population of performance Stratos have also led to the opening of preening studios in the urban centers of Tarrukar. These offer services such as preening, moulting baths, dye jobs and sale of feather products.
Feather prosthetics
Trivia
- Stratos feathers in general are deemed to be unhygienic, similar to shed hair in humans, so it's culturally encouraged for all Stratos to pick up after themselves and not leave shed feathers lying around. Due to this reason, many restaurants also ban the entrance of Stratos, or have designated exterior seating. This doesn't stop some Stratos celebrities from selling off their feathers, to moderate success.