Fishermen in a Norwegian fjord. Photo: S. Kipar

Dr. Kira Lancker from Leipzig presented the topic "Bioeconomic stock assessment for de-facto open access fisheries using catch and price data" to kick off the CeOS - seminar series this semester.

Stock assessments provide relevant information to manage fish stocks at sustainable levels. Methods based on fishery-independent data are costly, which may prevent effective management and causes geographic inequalities. Current affordable stock assessment methods routinely use catch data. We propose to use prices as additional data source in a new bio-economic stock assessment (“BESA”) approach for currently unmanaged stocks. With the zero-profit condition as measurement equation, we uncover biomass dynamics by use of the extended Kalman filter. Biological and economic parameters can be jointly estimated using maximum likelihood or Bayesian inference, thus providing a basis for both maximum sustainable and maximum economic yield management.