Variation in Great Tit nest mass and composition and its breeding consequences: a comparative study in four Mediterranean habitats

We would very much thank to all the people who have helped in the fieldwork at the different study areas over the years, to the students who assisted in nest dissection. We thank to the Spanish Meteorological Agency and to F. Atienzar for providing temperature data. This work has benefited from projects CGL2004-00787 and CGL2007-61395 (Ministry of Education and Science) and CGL2010-21933-C02-02 (Ministry of Science and Innovation).