Article Abstract:
A study of the comparison of pellets versus collected birds for sampling diets of Double-crested Cormorants was conducted to determine the diets of adults during both breeding and nonbreeding periods. Results reveal that there were no significant differences between pellets and collected birds in percentage masses. The methods used produced similar results for different length classes fish eaten. However, the time of the day may affect the comparability of the methods.
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Article Abstract:
The egg volume in the clutches of Great Crested Grebes remains constant after the first laid egg. Thus it does not add to the size hierarchy of the chicks arising from asynchronous hatching. The grebes start hatching before the clutch is over. This asynchronous hatching results in size and age hierarchy within the broods. Studies have been conducted at Lake Brabrand in eastern Jutland, Denmark.
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Article Abstract:
Podicipedidae are supposed to be unique in precocial families for the apportionment of egg composition as a function of egg size in Pied-billed and Horned Grebes. It is probable that the ontogeny and survival of grebe chicks varies according to egg size given the significance of egg composition to thermoregulation, developmental maturity, withstanding food deprivation, and hatchling growth.
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