Developing and applying a general abundance estimator for land-based predator surveys: Adélie penguins as a case study

The development of a general estimator of abundance would facilitate a standardised approach to regional and circum-Antarctic surveys of land-based predators. Such a generalised estimator is outlined, and its applicability illustrated by adapting it to the specific problem of estimating the abundance of Adélie penguins at regional scales in Antarctica, given a range of logistical scenarios and related survey designs.