IUCN / SSC Cat Specialist Group - Digital Cat Library
   

 

View printer friendly
Danell, A.C.; Andr‚n, H.
Precision beats interval: appropriate monitoring efforts for management of a harvested Eurasian lynx_ __Lynx lynx_ population
2010  Wildlife Biology (16): 409-418

Adaptive management of wild populations requires good knowledge of the population status. The main way to evaluate management performance is through recurring surveys, which often also serve as a decision basis for harvest quotas.We evaluated the effect of different survey reliabilities an frequencies during 1-4 years on management performance using a stochastic age and stage-specific population model for an Eurasian lynx _Lynx lynx_ population. As a proxy for management performance, we looked at the proportion of time that the population remained within a preferred interval, the proportion of time with no harvest, the average harvest number and the total number of surveys during the 50-year period in the simulation. In general, management performance increased with increased monitoring accuracy. More interestingly, a more reliable survey performed less frequently performed better than a less reliable survey performed every year. The management performance was not perfect even with complete knowledge of the population size at the survey, as annual variation in reproduction and survival between the survey (decision based on year t) and harvest (performed in year t+1) sometimes cause the population to be outside the preferred interval. If financial resources are limited, we recommend managers to minimise the error in the survey rather than to increase the frequency of surveys.

PDF files are only accessible to Friends of the Cat Group. Joining Friends of the Cat Group gives you unlimited access and downloads in the Cat SG Library for one year, and allows you to receive our newsletter Cat News (2 regular issues per year plus special issues). More information how to join here

 

(c) IUCN/SSC Cat Specialist Group ( IUCN - The World Conservation Union)