A simple approach for assigning the conservation status of freshwater fish based on their natural variability - a case study from the Iberian Ecoregion

作者：Sanchez Hernandez J^*; Cobo F; Amundsen P A

来源：Fisheries Management and Ecology, 2015, 22(2): 125-133.

DOI：10.1111/fme.12103

• fish conservation
• fisheries management
• natural population variability
• threatened species

A simple, non-lethal method for assigning conservation status is proposed based on three conservation classes (favourable, unfavourable/inadequate and unfavourable/bad) to fish species based on their natural population variability. To demonstrate this approach, conservation classes were allocated to three native fish species (brown trout Salmo trutta L., northern Iberian chub Squalius carolitertii (Doadrio), and northern straight-mouth nase, Pseudochondrostoma duriense (Coelho) based on basic population variables (density and biomass) using a 9-year dataset (2004-2012) from 15 different sampling sites in Spain. The classification of the population variables into conservation classes was made using previously described nonparametric methods and percentiles categorisation, and the current conservation status of the studied species was established. Temporal trend analyses showed that S.carolitertii experienced a progressive significant decrease during the study period, whereas both S.trutta and P.duriense exhibited weak increases in density. The study exemplifies the need to quantify the natural variability of fish resources to reveal their current conservation status and to determine whether short-term and long-term management actions are needed to rehabilitate native fish assemblages. The proposed approach could easily be employed by fisheries managers to monitor the conservational status of other native species.

• 出版日期2015-4