Waterfowl indexes, non-breeding

Trends of traversing and wintering waterfowl.

Data available from: 1975
Frequency: yearly

Changes to the previous version:
Of the next 6 fresh Rjks waters, the counting data is now also
included in the calculation of the national indexes and trends:
Naardermeer, Nieuwkoopse Plassen, Boezems van Kinderdijk, Abtkolk
and Putten, Zouwe Boezem and Swan water.
The indexes and trends of the following bird species have also been calculated:
Dwarf Goose, Geoorde Fuut, Large Canadian Goose, Large Silver Heron, Small
Silver heron, Crombek beach runner, Crowned, Tiny diver, Lepelaar and
Strandplevier.
For the indexes, the base year 2000 is set at 100.