Monthly waterbirds surveys in 2015 for Veta la Palma fish ponds in Doñana wetland, South Spain [Dataset]

All the ponds within the Veta la Palma system were surveyed monthly in 2015 by experienced observers as part of a monitoring program carried out by the Doñana Biological Station (EBD-CSIC, http:// www-rbd.ebd.csic.es/Seguimiento/seguimiento.htm). Owing to staff vacations, surveys did not take place in August. All aquatic birds present were identified to species and counted. We excluded raptors, corvids and other non-aquatic species from analyses. Every pond was visited on foot in a single day and surveyed from one or more positions along the shoreline with binoculars (8 x 50) and a telescope (20 x 60). Birds flying overhead were excluded. For each survey, the observers also identified the water level. Greater flamingos Phoenicopterus roseus are particularly abundant in the ponds (Rendón et al. 2008), and their behaviour also helped in the estimation of the water level as follows: 0 totally dry; 1 almost dry, with some dry regions in the pond and some shallow water; 2 low water level, roughly half way to the tibio-tarsal articulation of flamingoes; 3 medium level, approximately to the tibio-tarsal articulation; 4 high level, above the articulation but not exceeding total leg length