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Article

Detection ratios on winter surveys of Rocky Mountain Trumpeter Swans Cygnus buccinator

Jonathan Bart, Auteur ; Carl D. Mitchell, Auteur ; Michael N. Fisher, Auteur ; James A. Dubvsky, Auteur

Dans Wildfowl (57 2007)

We estimated the detection ratio for Rocky Mountain Trumpeter Swans Cygnus buccinator that were counted during aerial surveys made in winter. The standard survey involved counting white or grey birds on snow and ice and thus might be expected to[...]

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Article

Monitoring the shorebirds of North America: towards a unified approach

Susan K. Skagen, Auteur ; Jonathan Bart, Auteur ; BRAD Andres, Auteur ; STEPHEN Brown, Auteur ; GARRY Donaldson, Auteur ; B. Harrington, Auteur ; V. Johnston, Auteur ; S. L. Jones, Auteur ; R. I. G. Morrison, Auteur

Dans Wader Study Group Bulletin (100 2003)

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Article

Survey trends of North American shorebirds: population declines or shifting distributions?

Jonathan Bart, Auteur ; STEPHEN Brown, Auteur ; Brian Harrington, Auteur ; R. I. Guy Morrison, Auteur

Dans Journal of Avian Biology (38(1) JAN 2007)

We analyzed data from two surveys of fall migrating shorebirds in central and eastern North America to estimate annual trends in means per survey and to determine whether trends indicate a change in population size or might have been caused by o[...]

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