The effect of photoperiod on the timing of spring migration in the Bewick's Swan

Article Sidebar

PDF

Main Article Content

Eileen C Rees

Abstract

Bewick's Swans Cygnus columbianus bewickii floodlit from duck until 22.00 hr started their spring migration significantly earlier than birds illuminated until 20.00 hr; these latter, in turn, left before those receiving a natural photoperiod. The effects of variations in wind conditions and temperature and of snowfall, snowcover and disturbances, were also considered, but only the proportion of days with North to East ('head') winds had a significant influence on the departure pattern. In the case of food supplied to the birds the relevant factor was thought to be timing rather than the quantity of grain provided.

Article Details

How to Cite
Rees, E. C. (1982). The effect of photoperiod on the timing of spring migration in the Bewick’s Swan. Wildfowl, 119–132. Retrieved from https://tidsskrift.dk/Wildfowl/article/view/154219
Issue
Wildfowl 33
Section
Artikler

Articles in Wildfowl volumes 1-74 and in Wildfowl Special Issues 1-7  are not licensed under Creative Commons. In these volumes, all rights are reserved to the authors of the articles respectively.

The Wildfowl & Wetlands Trust (which published the journal from 1948–2020 inclusive) retains a royalty-free license in perpetuity to access and use pre-2021 issues for the purposes of research, which may involve sharing with research partners from time to time.

The copyright for this paper belongs to the Author(s). Papers published in Wildfowl 75 (in 2025) and subsequent issues are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

In the articles published in these volumes, all rights are reserved to the authors of the articles respectively. This implies that readers can download, read, and link to the articles, but they cannot republish the articles. Authors can upload their articles into an institutional repository.