In 2001 we started as part of the EU FP5 project Greenveins monitoring of bird communities in the normal landscape of Saxony-Anhalt (Germany) dominated by agricultural use. We selected four landscape sites of 4x4 km (Friedeburg (FBG), Schafstaedt (SST), Greifenhagen (GFH), Wanzleben (WAN)) and recorded birds according to the point count method (see Bibby, C.J. (2000) Bird census techniques. Academic Press, London). A central core area of 3 × 3 km within each sample site was divided into five square cells of 1 km² each according to a checkerboard grid. Within each of these 5 cells, 4 observation points were selected and at each point all singing, calling and seen bird species were registered within a radius of 250 m for 5 minutes. Surveys started around sunrise and ended about three hours later. Survey points were located far enough apart (> 500 m) to sample spatially distinct bird communities within each site. A bird survey within one year was performed with three visits in the following periods: (1) 1-30 April, (2) 1-20 May, (3) 21 May-20 June. Based on the birds recorded in the field, the observed bird numbers at each point were translated into territory numbers per species as an expert guess. With the start of the TERENO project (www.tereno.net) in 2009 contributing to the LTER network (Long-Term Ecosystem Research) in Germany (www.lter-d.de) and internationally as well (www.lter-europe.net) and the following surveys in 2012, 2013, 2014 the sites Harsleben (HAR) and Siptenfelde (SIP) were added. Although the monitoring program was designed to sample every three years, the years 2013-14 were taken as an additional check for variation of counts between years. Metadata about the sites and related activities and data sets can be found in the DEIMS Repository for Research Sites and Datasets (https://data.lter-europe.net/deims).

Supplement to: Frenzel, Mark; Everaars, Jeroen; Schweiger, Oliver (2016): Bird communities in agricultural landscapes: What are the current drivers of temporal trends? Ecological Indicators, 65, 113-121