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This could explain why there seem to be fewer birds than before the 2014 Goongerah/Deddick fires, even in the areas where the fire didn't reach. The thick smoke lasted for almost 8 weeks. Smoke impacts birds respiratory system, which is more efficient than mammals’ so they can absorb more oxygen (this allows them to fly) but they absorb more toxins as well.
...Why are birds more susceptible to the toxic effects of smoke? Short answer: because their respiratory system is more efficient than mammals’ so they can absorb more oxygen (this allows them to fly) but they absorb more toxins as well.
- Birds have more efficient oxygen binding in their red blood cells and more efficient oxygen transfer to the tissues
- Birds have “counter current” flow between the blood capillaries and air capillaries in their lungs, which means the flow of the air goes at right angles to the blood flow. This means at the beginning of the air flow (highest oxygen) the blood picks up a lot of oxygen and at the low oxygen end of the air flow the blood picks up a smaller amount of oxygen but it still picks up some– the end effect is that there is a much higher oxygen concentration in the blood.
- Birds also have a one-way flow of air through their respiratory tract, unlike mammals where the air goes in and then back out. They have air sacs in their body cavities and bones: the first breath goes into the abdominal air sacs, when they exhale it goes through the lungs, then when they inhale again that air goes into their thoracic air sacs and then out on the next exhalation. It is a lot more complicated than that but that’s the basic idea.
- Birds have a higher volume of air per breath and a higher respiratory rate so relatively more air goes through the system.
- The air sacs impart turbulence to the air flow so toxins and particulates can be deposited easier, and they can cause inflammation which can lead to localized infections. These infections (granulomas) are very difficult to treat especially if they are fungal infections....