Since 2002 we have been following a spotless starling population in woodland near Madrid, at the foot of Navacerrada mountains. The colony is currently formed by 250 nest boxes, with a very high occupancy rate. An intensive ringing campaign at the nest boxes takes place every year, two months before the laying season, and this allows capturing most of the adults present in the study site. We take extensive biometrical data, plumage colouration, behavioural observations, and blood samples from which physiological data can be gathered. Also, we fit adult birds with miniature microchips under the skin so that we can follow the bird behaviour at the boxes without further trapping. To do this, we count on microchip readers which are routinely set in the boxes and provide us with a good activity estimate before and during laying, nestling feeding etc. We monitor the breeding season of the entire colony from March to early July.

Yearly monitoring of the starling colony and performing the specific experiments of each breeding season constitutes a high workload. Fortunately, apart from the contribution of postdocs, PhD students and field technicians, we are aided by degree and master students, as well as by volunteers from many different countries.

This gallery is a kind of collage of the fieldwork performed in the colony from 2009 to 2014. We hope this would serve as a token of gratitude to all those who spend hours and hours, either in cold, rainy or hot days in the field. Thanks!

(All pictures, unless stated otherwise, were made by Lorenzo Pérez-Rodríguez)