This spring I’ve done just one spring census in Llobregat Delta. This census is inside the Catalan Common Birds Monitoring that ICO (Institut Català d’Ornitologia) is coordinating for several years in the whole country. Catalan Common Birds is based in two census during winter and two spring census, following always the same itinerary in order to get information about the commoner bird species.
I’ve seen several changes between this census and 2010 records. First of all there have been few riverside breeding birds records in comparision with 2010 census:
COMMONER RIVERSIDE BREEDING BIRDS
Cetti’s Warbler Zitting Cisticola Moorhen
2010 30 23 20
2011 19 11 10
There have been no migrant passerines recorded this year while 8 species were detected in 2010 (Redstart –Phoenicurus phoenicurus, Whitethroat –Sylvia communis, Subalpine Warbler –Sylvia cantillans, Grassopper Warbler –Locustella naevia, Bonelli’s Warbler –Phylloscopus bonelli and Woodchat –Lanius senator as more noticeable).
Different date in every census is not enough explanation for such a different records. 2010 census was performed on 7th May and 2011’s on 13th May.
