Snowy owl predation on lapland longspur nestlings recorded on film

T. W. Custer

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Snowy owl predation on lapland longspur nestlings recorded on film

T. W. Custer

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Abstract

During the summer of 1971 I investigated the breeding biology of the Lapland Longspur, Calcarius lapponicus , near Barrow, Alaska. To obtain data on incubation and feeding patterns of nesting longspurs, time-lapse cameras (Minolta Autopak-8 D6 super-8 movie cameras equipped with an Intervalometer-P time-lapse device) were positioned at several nests throughout the nesting season with an exposure interval of either 8 or 30 seconds. At 07:00 on 14 July a Snowy Owl, Nyctea scandiaca , took the three largest of four young at a nest being monitored at 30-second intervals (Figure 1). The nestlings were 4, 6, 7, and 8 days posthatching and weighed approximately 12, 15, 20, and 20 g respectively on 13 July.

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T. W. Custer. 1973. Snowy owl predation on lapland longspur nestlings recorded on film. https://pubs.usgs.gov/publication/1003125

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