Current global status of taimen and the need to implement aggressive conservation measures to avoid population and species-level extinction

摘要

An international effort carried out during 2011-2012 culminated in three completed IUCN status assessments of Hucho spp., thus completing assessments for all species in this and a related genus Parahucho. These species hold great ecological and evolutionary significance in the salmonid family, and are recognized as the largest salmonids in the world. Specialists have long recognized their precarious status. The reports conclude that all species of taimen are now listed as threatened or Data Deficient on The IUCN Red List of Threatened Species?, and point to a host of ongoing and emerging threats, including habitat loss and overharvest. I summarize the key data used to arrive at the status categories, and emphasize some key conservation measures that must be taken to avoid extinction at both the local population scale and at the species level. I provide some cautionary advice on the use of hatcheries to recover depressed populations and emphasize the need to undertake new research expeditions to assess the uncertain current status of Hucho bleekeri Kimura and Hucho ishikawae Mori.