The otter Lutra lutra suffered serious declines in Denmark during the 1960s and 1970s. A series of conservation and management projects were initiated to protect the remnant population, including national surveys and collection of otter carcasses. The recovery of the otter in Denmark since the 1980s was described by four national field surveys in 1984-86, 1991, 1996 and 2004 following the standard otter survey method, and by the geographical distribution of otter carcasses collected in 5-year periods prior to the field surveys. The surveys document a substantial increase in distribution range during the past 20 years. The number of collected carcasses increased annually by 9.1 ± 0.7% (mean ± S.E.) between 1980-2003. The spatial distribution of carcasses collected in the 5-year period prior to field surveys was correlated with regional site occupancy in field surveys. The implemented management practices are presented and discussed. We conclude that the standard otter survey method is a reliable method to monitor otter distribution range in Danish habitats, and that compiling records of otter casualties is a suitable methods to monitor long-term population trends.