Beat thewinter,andwhile some of thewintering birdsreturn to theirbreedingplacesin the North of Europe, we can make afirst estimation on how many birds spent the winter in the three constructed wetlands. In winter, the sample was takenevery 10 days, although the wind has made it difficult at times to keep this frequency.
For now,we can showroughly the state of play of the bird communitiesin each ofthese wetlands.Deliberately we are not going to enter into any statisticalanalysis toassess the differences in the habitat usebetween the constructed wetlandsand between species, the average number, diversityordominanceineach of thecommunitiesof birdsof each constructed wetland.That will be donein due course.
The Tancat de la Pipa has proven to be a constructed wetland used predominantly for certain waterfowl: the bluethroat (Luscinia svecica), kingfisher (Alcedo atthis), common chiffchaff (Phylloscopus collybita), common reed (Emberiza schoeniclus) and Cetti’s Warbler. In overall numbers, the daily catches are around 40 birds, and although there are differences between the sampling areas, it is not sufficient to say that there are environments that are significantly more used than others.
The Tancat deMilia, the result of a greater diversity ofhabitatssampled, also offersa more diversecommunityofwintering birds. Thus,typicalofwetlands, other bird species typical of more openenvironments are added such as meadowpipits(Anthus pratensis), white wagtails(Motacilla alba)and common chaffinches(Fringilla coelebs). However, the dominant speciesare reduced tothebluethroat, kingfisherandcommon chiffchaff. We can catch many of them, averaging over 50specimens byday, andin this case itis a clear evidence of the differences in habitat use by the whole community and by certain species.
The Tancat del’Illa is the space thathas a higheraverage number ofbirdscapturedfor study(about60 birds a day). However, it is tricky, because in thedivisions with the greatestdensity ofcattails common reed buntings settle down. Actually, if we eliminatethiskindoflist, this space would be dominatedoverwhelminglyby thecommonchiffchaff, but has an interestingpresence of moustached warblers, one of the speciesof interestin this project.
All those whoworkin trackingwildlifethere use aphrasethat we apply inour daily lives, “you cannot keep whatyou do not know.” We have muchworkto do to deal with the thousands ofdetails while having studied about 1000 birds so far. Thus, we continue studying our birds and know them a little better each time to be able to establish management plans to preserve them in the most effective manner.