The document discusses hierarchical models for species distributions and the importance of including sampling models in species distribution modeling. It presents different observation models (Binomial, Poisson, Bernoulli, no observation model) that account for sampling effort and compares their predictions on species distribution data from the UK. The key points are that sampling effort needs to be measured and accounted for, different effort estimates can lead to different sampling models, and sampling models should be included in species distribution modeling to improve predictions.