A Procrustean assessment of the European eel stock

Abstract

No assessment of the state of the European eel stock is available due to the absence of adequate data for many areas of the continent. In contrast to past efforts which turned to complete the traditional catch composition data, and which met with little success, we will try to develop a simplified cohort-model (based on life stage, rather than age or size), simple enough for the available data.

Under the (incorrect) assumption of stable recruitment and exploitation, the catch-at-life-stage analysis yields a preliminary assessment of the entire European stock, and for the glass eel importing and exporting countries. Recruitment is estimated at about 2000 million eels annually, most of whom enter countries around the Bay of Biscay, supporting intensive glass eel fisheries. Elsewhere, the natural recruitment is outnumbered by imported and transported glass eel. The fishing mortality rate accumulated over the total life span is estimated at 5.21 (=99%) for glass eel exporting countries and 3.25 (=96%) for glass eel importing countries.

This Procrustean assessment provides a limited view on continent-wide stock. Substantially improved assessments are unlikely at the time-scale at which management action is required. However, the development of a co-ordinated system of inter and intra-national management (i.e., the only effective levels) will benefit the assessment of the European eel stock.