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Unformatted text preview: Reasons for molt: 1. Replacement of worn feathers 2. Change the color and shape of feathers Molting cycles: Prejuvenal molt – 1 st molt of a bird’s life – natal down replaced by juvenal plumage Prebasic molt – juvenal or alternate plumage replaced with “non-breeding” plumage. This is always a complete molt (all feathers). Usually occurs in winter Prealternate molt – basic plumage replaced with “breeding” plumage. Usually occurs in summer. Thyroid hormones are important for all three types of molt. Molt Patterns: 1. Complete prebasic Complete prealternate (rare) 2. Complete prebasic Partial prealternate 3. Complete prebasic No prealternate...
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- Spring '09
- Feather, Prealternate molt, plumage Prebasic molt, insulation Contour feathers, Age Season Molt, feathers Molting cycles