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USGS · 70031228

Growth and energy requirements of captive-reared Common Loon ( Gavia immer ) chicks

F. Fournier·W. H. Karasov·K.P. Kenow·M.W. Meyer
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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 ≈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.

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F. Fournier, W. H. Karasov, K.P. Kenow, M.W. Meyer. 2007. Growth and energy requirements of captive-reared Common Loon ( Gavia immer ) chicks. https://doi.org/10.1642/0004-8038(2007)124%5B1158%3Agaeroc%5D2.0.co%3B2

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