Frequency, Timing and Costs of Intraspecific Nest Parasitism in the Common Eider

Abstract

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Egg-Laying Time and Laying Interval in the Common Eider

“…Young Eiders and Eiders in poor condition are known to lay later in the season (Spurr and Milne 1976), also clutch size decreases over the season (Robertson et al 1992). Therefore, these young birds or birds in poor condition, that lay small clutches, could also be taking longer to lay their eggs, and the converse could be true for Eiders in good condition.…”

Breeding Ecology of Sympatric Greater and Lesser Scaup (<i>Aythya marila</i> and <i>Aythya affinis</i>) in the Subarctic Northwest Territories

“…Several previous studies also reported higher rates of hatchability of eggs from mainland versus island nests (Hammond and Mann, 1956;Duebbert et al, 1983;Hines and Mitchell, 1983). High densities of waterfowl nesting on islands have frequently led to increased levels of egg parasitism (Hilden, 1964;Vermeer, 1968;Giroux, 1981;Hines and Mitchell, 1984;Robertson et al, 1992), and lower hatchability of eggs (Newton and Campbell, 1975;Duebbert et al, 1983), which is probably due to age differences between host eggs and parasitically laid eggs. Once parasitized clutches were eliminated from our analyses, the hatchability of eggs in both study areas was similar.…”

Two grouse clutches in the same nest: evidence for nest site adoption in capercaillie (Tetrao urogallus)

“…The feathers found in the nest belonged to the mother of the hatched chicks; most likely this was the incubating hen. Clutches with eggs from several conspecifics have been described for a number of bird species, and perhaps most commonly for ducks and geese (MacWhirter 1989;Erskine 1990;Lank et al 1991;Sorenson 1991;Weigmann and Lamprecht 1991;Robertson et al 1992;Bjorn and Erikstad 1994;Eberhard 1996;McRae 1995;Beauchamp 1997;Kenaga 1997;Payne 1998;Robertson 1998).…”