Progress and status of river otter reintroduction projects in the United States

  • Published source details Raesly E.J. (2001) Progress and status of river otter reintroduction projects in the United States. Wildlife Society Bulletin, 29, 856-862.


This study is summarised as evidence for the following.

Action Category

Translocate to re-establish or boost populations in native range

Action Link
Terrestrial Mammal Conservation
  1. Translocate to re-establish or boost populations in native range

    A study of projects carried out in 1976–1998 across 48 states in the USA (Raesly 2001) found that following translocations, river otter Lutra canadensis populations and ranges expanded in most states. Of 21 states with reintroduction programs, 15 reported having growing river otter populations, one reported a stable population and three reported stable to growing populations. Two states reported that it was too soon into their programs to judge population trends. Evidence of reproduction was reported from 18 states (82% of states with reintroductions), and range expansion was reported in 17 states (77%). In 1976–1998, river otter releases totalled 4,018 animals in 21 states. In six states, otters had been extirpated while in 15, reintroductions took place in parts of the state from which otters were absent. Releases involved an average of 19.6 otters/site. Information was gathered from telephone interviews in August–September 1998.

    (Summarised by: Rebecca Schoonover)

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