Fournier, F., Karasov, W. H., Kenow, K. P., and others, 2007, Growth and 
Energy Requirements of Captive-Reared Common Loon (Gavia Immer) Chicks: Auk, 
v. 124, no. 4, p. 1158-1167.


Abstract

We measured the energy requirements during postnatal development of six hand-
reared Common Loon (Gavia immer) chicks using continuous feeding trials and 
doubly labeled water. At fledging, the mean ( SE) body mass of chicks was 
3,246 51 g. They reached asymptotic body mass in similar to 66 days and had a 
mean growth rate constant of 0.089 +/- 0.002 day(-1), which was greater than 
growth rate constants of other, similar-sized precocial birds. Between hatch 
and day 66, chicks allocated 16.5% of their metabolizable energy to new 
tissue, lower than the average for other bird species (20%), which might be 
expected considering their precocial mode of development. There was a 
developmental change in the assimilation efficiency of food (metabolizable 
energy coefficient), with a mean of 0.64 +/- 0.03 in chicks aged 21 days, 
rising to 0.83 +/- 0.07 in chicks aged 35 days.

Keywords

Allocation, Common Loon, Digestion, Gavia Immer, Growth, Metabolizable 
Energy, Production, Respiration, Salmo-Gairdneri, Rainbow-Trout, Mercury