What aspect of post-hatching care suggests the immediate period is highly vulnerable for chicks?

Answer

Parents are almost constantly shuttling chicks, feeding them, or adjusting the nest

The intense involvement of parents constantly attending to the chicks, feeding them, or adjusting the nest suggests the immediate post-hatching period requires near-constant parental vigilance.

What aspect of post-hatching care suggests the immediate period is highly vulnerable for chicks?
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