  We develop a new statistical procedure to monitor, with opportunist data,
relative species abundances and their respective preferences for dierent
habitat types. Following Giraud et al. (2015), we combine the opportunistic
data with some standardized data in order to correct the bias inherent to the
opportunistic data collection. Our main contributions are (i) to tackle the
bias induced by habitat selection behaviors, (ii) to handle data where the
habitat type associated to each observation is unknown, (iii) to estimate
probabilities of selection of habitat for the species. As an illustration, we
estimate common bird species habitat preferences and abundances in the region
of Aquitaine (France).
