It is red because of blood mixed into the spit of the swift. As nests are harvested, the swift has to rebuild its nest and this takes a physiological toll on the bird (because the eggs, which are not yet laid great tax the bird's system).
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Some time ago people believed that a red nest was created by an overworked Swiftlet that had built its nest partly with blood. Nowadays, people believe that the red nest is created by a Swiftlet that has eaten seafood or a food substance which contains a high volume of iron. Research has proved both of these beliefs to be untrue. The red nest (red blood) is not created by the Swiftlet, but by the surrounding environment.
Cave nests turn red in colour due to the mineral content and the wet surface of the cave which seeps into the nest. This polluting of the nest by cave water significantly reduces the nutrient levels of the nest. The red appearance of a house nest is achieved through the unethical dying of white nests. The harvest is deliberately delayed to let the gas from the Swiftlet's droppings react with the nest. The gas emitted by the Swiftlet is called Ammonia. Ammonia is a compound found in fertilizer and detergent.
Long term consumption of bird's nest which has been contaminated in this way will have adverse effects on personal health. The consumption of toxic chemicals has strong links to cancer and other major illnesses. This is the reason all bird's nest experts advise expectant mothers and the elderly to avoid the consumption of red nests.
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The above is based on researches and reports released by Pureness Bird's Nest
pooping pandas
Bird's nest soup is a Chinese delicacy. It is made from the nest of a swiftlet, a bird in southeast Asia.
It is literally a birds nest made from edible fibers. Usually a swallow's nest :)
the size of a soup bowl
Spain. they nest every summer mostly in the south
No, it's not cruel. However, it depends on how you define cruelty. If you think honey is cruel, then, yes, you might consider birds' nest soup cruel. Most harvesters would not bother those nests with egg on them. So, consider birds' nest as an expensive honey that only can be afforded by those few.
Authentic bird's nest soup is made using the nests of the swiftlet, a tiny bird in southeast Asia. The swiftlet lives in dark caves. Instead of twigs and straw, the swiftlet makes its nest from strands of its own gummy saliva, which hardens when exposed to air.
It is quite possible as there IS a delicious soup that is called "Bird's Nest Soup". It is considered to be quite the delicacy & IS NOT made from a bird's nest.
Sometimes they can make out where a nest came from or if it is man-made or not. They will probably live there if they don't have a choice, but some birds would rather build their own nest.
The nest was built by birds.
it looks like a birds nest
Because the design is based on a birds nest. If you look at the contruction of an actual birds nest it is very similar to the bird cage. Especially if viewed from the air.
A nest is often made of organic material and it is where birds lay their eggs. A roost is a place with support where birds commonly gather, not necessarily for laying their eggs.