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Updated: Jan 9, 2026
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Manipulation of Color Patterns in Jumping Spiders for Use in Behavioral Experiments
Published on: May 21, 2019
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Condition-Dependent Feather Color Change and Condition-Independent Pheomelanin Loss in the Barn Swallow
Masaru Hasegawa1, Emi Arai2, Shosuke Ito3
1Department of Environmental Science, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan, perorobomusadiobe@gmail.com.
Zoological Science
|December 6, 2025
Summary
Barn swallow feather color fades seasonally, with reduced redness and pheomelanin pigment. This color change, influenced by body condition, suggests other pigments also affect feather coloration.
Area of Science:
- Animal behavior
- Avian biology
- Coloration mechanisms
Background:
- Feather coloration is a sexually selected trait in many bird species.
- The mechanisms driving seasonal changes in feather color are not fully understood.
- Pheomelanin is a primary pigment responsible for reddish feather colors.
Purpose of the Study:
- To investigate if within-season feather color change in barn swallows correlates with changes in pheomelanin.
- To determine factors influencing feather color and pheomelanin content changes.
Main Methods:
- Tracking seasonal changes in the redness of barn swallow (Hirundo rustica) throat feathers.
- Quantifying pheomelanin content in feathers over time.
- Analyzing the influence of capture date, year, sex, and body condition on color and pigment changes.
Main Results:
- Barn swallow feathers became less red over time, indicating fading.
- Pheomelanin content significantly decreased as the interval between captures increased.
- Feather color change was condition-dependent, while pheomelanin loss was condition-independent.
Conclusions:
- Seasonal pheomelanin loss alone does not fully explain barn swallow feather color changes.
- Condition-dependent color alteration suggests other pigments or factors are involved.
- Future research should explore additional colorants impacting animal coloration signals.
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