19/12/2019
Dec. 15, 2019
Daffodil spends a lot of time preening.
The preen gland, is an essential part of preening. It is found near the base of the tail and produces an oily, waxy substance that helps waterproof feathers and keep them flexible. While preening, birds spread this oil to each feather so they are evenly coated and protected. The special gland is one key physical trait that helps to keep ducks on top of the water. This gland, located at the base of their tail, produces an oil that the ducks spread over their bodies to make their feathers water-repellent. Since duck feathers resist getting saturated with water, the birds weigh less than they would if their feathers absorbed that water.
In addition to their waterproofing abilities, duck feathers possess another quality that helps them to float: They trap air. The birds' feathers are tightly interlocked with a system of barbs that hold air in. If they need to dive underwater for a quick snack, they just squeeze the air out by pressing in their feathers. They trap the air again soon after resurfacing and shaking off.
Ducks also have a system of internal air sacs that helps to keep them buoyant. They keep these sacs filled with air unless they want to dive under the water, at which point they squeeze the air out. The sacs, which include the duck’s lungs and are located along the length of the duck’s central body, are the equivalent of having miniature helium balloons inside.