HEMATOCRIT VALUES IN CHINSTRAP PENGUINS (PYGOSCELIS-ANTARCTICA) - VARIATION WITH AGE AND REPRODUCTIVE STATUS

We studied haematocrit variation with age and reproductive status in c hinstrap penguins (Pygoscelis antarctica) at Deception Island, South S hetlands. There was a significant difference in haematocrit values bet ween different age groups (adults vs nestlings and juveniles). Adults had a higher haematocrit value than juveniles and nestlings and juveni les had higher haematocrit values than nestlings. There was also a sig nificant difference in haematocrit values between adults of different status (breeding vs moulting). Breeding adults had higher haematocrit values than moulting adults. The observed differences between age grou ps were thought to be the result of different oxygen demands due to ex ercise. The observed differences between adults of different status co uld reflect the different demands associated with reproduction and mou lt fasting.