Interaction Between Early Experience and Depth Avoidance in Young Eider Ducks (Somateria Mollissima L.)

Abstract Speed estimations of eider broods descending into the sea for the first time revealed no hesitation between ground and depth at the shoreline. In a laboratory experiment, however, dark-reared young (N = 10) exhibited strong resistance when pushed from the shallow towards the deep side of a...

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Bibliographic Details
Published in:Behaviour
Main Authors: Nyström, Mats, Hansson, S.B.
Format: Article in Journal/Newspaper
Language:unknown
Published: Brill 1974
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Online Access:http://dx.doi.org/10.1163/156853974x00372
https://brill.com/view/journals/beh/48/1-4/article-p303_16.xml
https://brill.com/downloadpdf/journals/beh/48/1-4/article-p303_16.xml
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Summary:Abstract Speed estimations of eider broods descending into the sea for the first time revealed no hesitation between ground and depth at the shoreline. In a laboratory experiment, however, dark-reared young (N = 10) exhibited strong resistance when pushed from the shallow towards the deep side of a visual cliff apparatus. The same young hesitated in crossing from shallow to deep when lured by playbacks of the female's grock-call. In contrast, differential reactions to depth were absent during free swimming in a water-filled visual cliff. In another experiment, young exposed to a deep texture (N = 21) for 2 to 24 hours revealed significantly more deep choices than a matched group of shallow-exposed (N = 20) and a group of unexposed young (N = 7). Although choice preferences were in line with the type and quantity of early experience, it is concluded that there also exists a predisposition to learn or be acquainted with a near texture faster than a distant one. The problem posed by the conflicting tendencies in nature of remaining proximate to the female versus descending into depth is discussed in relation to the age and predation of the young.