When a bird power triggers a chain of effects that activate additional bird powers, the order of resolution is as follows:

• Brown "WHEN ACTIVATED" powers in a habitat are always activated from right to left as you move your action cube across the row. This is specified for each habitat action (Gain Food, Lay Eggs, Draw Bird Cards) and applies to any chain of effects that result from activating these powers.

• If a bird power causes you to take an action that would activate more bird powers (for example, drawing a card that triggers another effect), you continue to resolve the powers in the right-to-left order within that habitat.

• All bird powers are optional; you may choose whether or not to activate each one as you reach it.

This order is supported by the following rulebook references:

• "Activate any brown powers on your [habitat] birds, from right to left. All powers are optional."
  (Pages 7, 8, 9)
• "These powers may be activated from right to left whenever you use the corresponding habitat."
  (Page 10)

Summary:
When a chain of bird powers is triggered, resolve each power in the right-to-left order within the habitat row, choosing whether or not to activate each as you go.

Source: pages 7, 8, 9, and 10.

Source: Core Rulebook (pp. 10, 4, 7, 8, 9)