1. Altricial Birds (Helpless at Hatching):
- Nestling Period: 2-3 weeks (e.g., robins, sparrows)
- Fledging Period: 1-3 weeks (after leaving the nest)
2. Semi-Altricial Birds (Partially Developed at Hatching):
- Nestling Period: Around 2 weeks
- Fledging Period: A few days to several weeks
3. Precocial Birds (Relatively Independent at Hatching):
- Nestling Period: Short (less than a week)
- Fledging Period: Can leave the nest within a day or two
It's important to note that the specific timeframes may vary within bird families, and some species might have longer or shorter nestling periods and different fledging behaviors.