Diving Physiology Flashcards
What contributes to buoyancy in seabirds?
Body density and trapped air
How do diving birds overcome buoyancy
Birds fluctuate from positive to neutral to negative buoyancy
What are some challenges that diving birds face?
- The viscosity and density of water compared to air
- Fueling activity with oxygen while not breathing
How are penguins morphologically adapted for diving?
- Streamlined body shape
- Dense bones (not pneumatic)
- Webbed feet
- Specialized feathers
- Stiff wings with fused bones
What happens to the diving duration of seabirds when body size increases?
The dive duration will increase (more oxygen capacity)
Apnea
Holding your breath
How do seabirds conserve oxygen during Apnea?
- Increase their oxygen storage capacity
- Bradycardia
- Peripheral ischemia
Bradycardia
Decrease in heart rate
What are the affects of bradycardia
- Increased amount of oxygen storage capacity
- Decreased amount of oxygen consumption
Peripheral ischemia
Reduced blood flow to the extremities
Why are bird lungs more efficient than mammalian lungs?
There is no mixing of oxygen rich air and oxygen poor air (gas exchange is more efficient)
What happens to the solubility of gasses as underwater pressures increase?
Solubility will increase
Describe “the bends”
- As dive depths increase solubility of gases increase
- On Acension gas solubility decreases as pressure decreases
- Gasses dissolved in cells release in the form of bubbles
- End result is “the bends”
What do marine mammals do to prevent “the bends”
- As pressure increases, the lungs will collapse
- Air moves into rigid structures
- Gasses do not get dissolved in the blood
How do shallow diving seabirds deal with increased dive pressures?
- The do not dive deep
- Shallow dives = not enough dissolved gasses to cause “the bends”
