The LIFE Ricoti project attends the XXIII Spanish Ornithology Congress

On the occasion of the XXIII Spanish Ornithology Congress, held in Badajoz in November 2017, the LIFE Ricotí project showed some of the first results obtained in the preparatory actions carried out during 2017. In total, three posters and an oral communication were presented, which dealt with different aspects of the biology of the species. Each of them are summarized below:

- Are better males those who defend the territory more intensely? (poster 1)

This study evaluates the territorial behaviour of males according to the density of competitors and their body condition. The results obtained indicate, contrary to what might be expected, that Dupont’s lark males show higher rate of display (calls) in lower density areas, while no significant relationship with body condition was found. This could be reflecting the effect of high number of satellite males occupying close areas but with a low intensity display, which leads us to ask a crucial question: how many of these males are actually mating and therefore actively contributing to population growth?

- Does male body condition depend on intra-sexual competition or on ectoparasites load? A case study with the Dupont’s lark (poster 2)

Body condition depends on multiple factors, including intra-sexual competition, parasite load and phenology. We analysed these three variables in several populations of Dupont’s lark in southern Soria, finding a negative relationship between first two variables and male body condition (a higher intra-sexual competition and more parasite load correspond to a worse body condition). We also found that, as the breeding season progresses, male body condition tends to diminish, while ectoparasites load rises, which is probably explained by costs associated with the reproductive effort of animals.

- Does intra-specific aggregation vary according to density? Spatial aggregation patterns in three species of steppe birds in the province of Soria (poster 3)

In this study we explored the effect of density of co-specifics (individuals of the same species) on the spatial aggregation pattern of Dupont’s lark and two other common bird species in Soria steppes during the breeding season: the Eurasian skylark (Alauda arvensis) and the Tawny pipit (Anthus campestris). The results showed that, while in the case of Eurasian skylark the aggregation pattern appears to be evolutionarily determined (though it may be modulated by co-specifics density), Tawny pipit and Dupont’s lark aggregation pattern is related to territorial behaviour, regardless of density.

- Population trends of the Dupont’s lark in Spain (poster 4)

We evaluated population trends of Dupont’s lark in Spain during the period 2004-2015, as well as the category of threat according to the criteria of population size reduction. We have estimated a dramatic decline of 41.3% over the last 12 years. Thus, the species should maintain its “Vulnerable” status at national level, but Andalusia and Castilla y Leon should classify the species as “Endangered”.

Israel Hervás and TEG Ricotí-UAM team