Dump Nesting in a Missouri Wood Duck Population

Factors Influencing Incubation Egg-Mass Loss for Three Species of Waterfowl

“…Studies of this behavior rely on numerous methods to detect parasitism, some of which can be fairly labor intensive and expensive. Some of the more laborious methods include observing individual nests daily (Semel and Sherman 2001) and calculating the rate of egg deposition on the basis of the egg-laying rates of individual females (Jones and Leopold 1967, Clawson et al 1979, Semel and Sherman 1992. Microsatellite and fingerprinting techniques are accurate (MacWhirter 1989, Andersson and Åhlund 2000, Roy Nielsen et al 2006a but are also labor intensive and come with the additional drawback of being relatively expensive compared to other methods.…”

Egg-laying, incubation and intraspecific nest parasitism by the Mandarin DuckAix galericulata

“…Usually the daily rate of egg-laying for this species has been calculated from visits to nest sites at intervals longer than 1 day. 2,5,6,10 Both methods have produced comparable estimates of the incidence of intraspecific nest parasitism for this species. However, for the Mandarin Duck the proportion of eggs laid parasitically calculated from weekly visits was only half the true proportion for the same sample of clutches.…”

“…It is, therefore, possible that a female laying eggs parasitically at one nest site is responsible for the break in lay at another, as has been demonstrated for marked individuals of the Carolina Wood Duck. 2 In this species, threequarters of hens laid eggs parasitically before establishing and incubating a nest of their own. 4 Whilst undoubtedly some breaks in lay will have a physiological basis, we propose that for the Mandarin Duck during the laying period of a clutch, a break in lay either signals a change of hen laying into a clutch, or the same female laying into another clutch.…”

“…The latter, so-called non-term eggs, 2 therefore, only contain partially developed embryos when ducklings from the rest of the clutch leave the nest. 2 '5'6 *To whom correspondence should be addressed. Davies & Baggott l proposed that the variable clutch size of the Mandarin Duck was, as for the Carolina Wood Duck, a production of intraspecific nest parasitism, and reported that clutch sizes were different in artificial and natural nest sites.…”

Clutch size and nesting sites of the Mandarin DuckAix galericulata

“…3 The Mandarin Duck can be induced to nest in boxes, 3 as was found for North American wood ducks. 4 For the Mandarin Duck most authors report the clutch size as 9-12, occasionally 14 eggs.8 This is attributed to intraspecific nest parasitism, 8 which manifests itself as 'dump nesting', 9 where more than one female lays eggs into the same nest site and the clutch is subsequently incubated by a single female. Our paper describes the variability of clutch size for the Mandarin Duck, where this is defined as the number of eggs laid into a nest site; we also report differences in clutch size in relation to the type of nesting site.…”