Annual national population indices of butterflies in the Netherlands since 1992Chrisvan SwaayDe Vlinderstichting - Dutch Butterfly ConservationPostbus, 506AM WageningenNL-6700The NetherlandsChrisvan SwaayassociatedParty2013-02-06Annual national monitoring data of De Vlinderstichting - Dutch Butterfly ConservationThe nationwide data of population indices and information on number of plots are freely available from the URL above.
Important note: if other information or levels of aggregated data are required, resources will need to be made available to pay for the time of De Vlinderstichting staff. Raw data cannot be supplied (as per communication from Chris van Swaay).
Attached is the data that is freely available on-line as of June 2012. Check the above website to see whether an updated file has been released. Data set owner involvement/permission only necessary if additional data is needed. See above comments.no restrictionsThe Netherlands (nationwide data)5.54925.549252.316752.3167199256 speciesSpeciesButterfliesChrisvan SwaayDe Vlinderstichting - Dutch Butterfly ConservationPostbus, 506AM WageningenNL-6700The Netherlandschris.vanswaay@vlinderstichting.nl Weekly line transectsWeekly line transect counts
Indices are calculated using TRIM with a weighting procedure to account for distribution of transects
Length of the transects depend on habitat quality and availability
Data for 2000 is set to 100 as a reference point see
http://www.vlinderstichting.nl/actueel.php?id=301attached_fileNot authorized to access resourceOtherattached_fileNot authorized to access resourceOther timeseries yearly