Related Experiment Videos
Refeeding signal in fasting-incubating king penguins: changes in behavior and egg temperature
R Groscolas1, F Decrock, M A Thil
1Centre d'Ecologie et Physiologie Energétiques, Centre National de la Recherche Scientifique, 67087 Strasbourg Cedex, France. rene.groscolas@c-strasbourg.fr
Summary
King penguins exhibit a "refeeding signal" triggered by critical body mass loss during fasting. This leads to egg abandonment and feeding behavior, offering insights into metabolic control of feeding.
Area of Science:
- Animal Behavior
- Physiology
- Ecology
Background:
- Spontaneously fasting birds may have a
- refeeding signal
- operating below a critical body mass threshold.
Purpose of the Study:
- Investigate the refeeding signal in fasting-incubating king penguins.
- Determine the relationship between body mass, fasting duration, and egg abandonment.
Main Methods:
- Continuous video monitoring and biotelemetry to track behavior and egg temperature (T(egg)).
- Comparison of penned birds (prevented from partner relief) versus normally relieved birds.
Main Results:
- Penned birds fasted longer, lost more weight, and abandoned eggs approximately 1 week after reaching critical body mass.
- Transitory egg abandonments preceded definitive abandonment, accompanied by display songs indicating readiness to feed.
- Egg temperature decreased significantly in the final days before abandonment.
Conclusions:
- The refeeding signal appears to be stimulated at a threshold body mass, indicating critical fat store depletion.
- Fasting-incubating king penguins serve as a valuable model for studying metabolic control of feeding behavior related to energy status.