BIRCHARD, G.F.*; DAUGHERTY, C.H.: Energetic of Development in the Fairy Prion (Pachyptila turtur)
Embryos of the Procellariiformes are noted for their very long incubation times. The limited data available on embryos from this group indicates that these long development times are associated with increased costs of development. We measured the oxygen consumption rate of developing embryos of the fairy prion (Pachyptila turtur), a small procellariiform, from early in incubation until internal pipping (IP) occurred. Average egg mass in this species was 25g. The oxygen consumption rate showed an exponential rise with time. There appeared to be a short plateau period two days prior to IP which occurred on day 42 of an estimated incubation time of 44.5 days. The pre-IP oxygen consumption rate averaged 238 ml O2/d. Integration of the area under the curve to the time of IP gave a total of 2924 ml O2 consumed, a pre-IP cost of development of about 57.4 kJ. The incubation time of the fairy prion is 188% of the value predicted from existing allometric equations. The pre-IP energy consumption was not significantly different from predicted values. The cost of development was increased (184% of predicted values) as previously observed in this group. Analysis of deviations from predicted values for incubation time and cost of development for procellariiform embryos shows a significant effect of egg mass. Decreasing egg mass shows a consistent increase in the deviations observed.
