Whitefish, Coregonus lavaretus (L.), in the fisheries management of Lake Gołdopiwo (Northeastern Poland) from 1950 to 2005

Abstract

The aim of this study was to analyze the growth rate of whitefish, Coregonus lavaretus (L.), in Lake Gołdopiwo in the 1932-1999 period. The magnitudes of catches and stocking during the 1950-2005 period were also determined. Once the studied population reached the maximum density, the growth rate diminished distinctly but commercial catches remained at a very high level for the subsequent 21 years at an annual mean of 8181 kg, and 9.5 kg ha^-1. Throughout the entire study period, no significant relationship was noted between the magnitudes of catches and stocking. The cause of the collapse in whitefish exploitation in Lake Gołdopiwo must be sought for in disadvantageous changes in the environment and decreasing fisheries exploitation.

CORRESPONDING AUTHOR:

Stanisław Falkowski, Instytut Rybactwa Śródlądowego, Zakład Bioekonomiki Rybactwa, ul. Oczapowskiego 10, 10-719 Olsztyn; Tel./Fax: +48 89 5240171, +48 89 5240505; e-mail: sfalkowski@infish.com.pl