Abstract. The European wild rabbit (Oryctolagus cuniculus) is a species native to the Iberian Peninsula, where it was once extremely abundant. It is considered the most important prey item for the peninsula's assemblage of Mediterranean vertebrate predators, which includes two endangered specialist rabbit feeders, the Spanish imperial eagle (Aquila adalberti) and the Iberian lynx (Lynx pardinus). However, rabbit population trends in Spain have not been accurately documented. In the present study, we analysed trends in a population of European rabbits monitored over 23 years in the Doñana National Park, home to one of the most diverse and densest predator communities in Europe. Rabbit abundance and population trends were estimated using roadside counts. Results show that the rabbit population declined sharply by ~60% during the first wave of epizootic rabbit hemorrhagic disease (RHD) in 1990. Since then, rabbit numbers have declined at a relatively constant rate and the species has become progressively scarcer in the area. The current population is less than 10% of that before the arrival of RHD. However, after the RHD epizootic we observed increasing intra-annual population recruitment. We hypothesise that density-dependent factors caused by enzootic viral diseases (myxomatosis, RHD) and higher predation of rabbits are the main factors preventing recovery of rabbit numbers. The effects of a decline in the prey species on the ecology of sympatric rabbit predators are discussed, and measures to improve ongoing rabbit conservation efforts are suggested.

The relationship between begging behaviour, chick nutritional state, and parental distribution of food within broods was studied in 4‐ and 5‐chick magpie Pica pica broods under natural conditions. Three components of the begging display (duration, latency, and posture) were highly correlated with each other and also with the emission and duration of begging calls. Begging performance was strongly influenced by the food intake of nestlings during the preceding 1‐h interval, indicating that begging may reliably reflect the nutritional need of nestlings. Daily growth during the preceding day, as well as average cumulative food intake by the brood during the preceding 24 h, seemed not to affect begging in a similar way. Begging signals employed by hungrier nestlings involved a higher degree of muscular activity, thus supporting the prediction that nestlings in greater need should employ more costly signals. Overall, those nestlings who begged more tended to obtain more food, but the relationship between feeding success and begging behaviour was weak due to a high variation between broods in the way that parents seemed to respond to variations in begging behaviour. Possible causes for this variation, and its implications for the evolution of reliable begging displays, are discussed.

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