The EU Habitats Directive provides in Annexes II and IV a list of species needing to be
conserved. Member States have implemented a variety of conservation measures in response
to this obligation. These measures include the rejection, modification or delay of land
development plans, payments for landowners to perform conservation measures and
management actions such as breeding programmes. The costs of the various conservation
measures are not always apparent. There may be an underestimation of the resulting costs
when land development plans are altered, because there is no visible flow of financial
resources. Such a biased perception may result in selecting conservation measures with high
but less visible costs, whereas conservation measures with low but more visible costs are
neglected. The purpose of this paper is to contribute to avoiding a biased selection of
conservation measures by presenting a framework which captures a broad variety of costs
relevant to the conservation of species protected by the Habitats Directive. We also
demonstrate the relevance of a biased selection of conservation measures by using the
framework to empirically estimate the costs of protecting the common hamster (Cricetus
cricetus) in the region of Mannheim, Germany. We find that the less visible costs of changes
in development plans are significantly higher than the more visible costs of payments to
landowners and management actions. This result suggests that measures with visible costs
should be given more attention in the future.