This paper is an evaluation of the present recruitment situation of Glass Eels based on the United Kingdom’s Industry’s figures and researching the local historical records. Is ICES “sound-bite” figure of 1% of 1980 recruitment levels correct? Certainly “back” calculations do not substantiate this figure with reference to the UK Industry’s records. Nor does it seem likely that the same “back” calculation based on the French situation is believable. The UK records can substantiate a 20% decline from 1980’s levels. Consideration is then given to the decline of glass eel recruitment, when did this begin? Although the last 25 years have been important, the destruction of the habitat & migration routes of Anguilla anguilla probably began with the Industrial Revolution. The methods used by the migratory eels to “climb” the river systems and the effect of the hard & soft barriers on the tidal effect and migratory mechanism are reviewed. A consideration is given to the habitat and various barriers that reduce the migration of glass eels. Will reducing the fishing effort without compensation for the loss of environment be an effective recovery measure? Finally looking to the future and how barriers to migration and damage to the habitat could be negated at the planning stage of both large civil

Introduction

There are four questions to ask about the decline of the eel population.

1.	“Is the European stock of Anguilla anguilla outside safe biological limits and its population dangerously close to collapse?”

1.	“How and why are humans influencing the population change, and to what degree?”

1.	“Can management effect eel population change predictably by adjusting one or two factors out of the many involved?”

1.	But perhaps the most fundamental question is: “Can humans manipulate the population change predictably?”

Or, more scientifically: Will reducing the fishing at the margin produce a linear, predictable change in the eel population.

The answer must be “No”.

So in such complex, coupled, non-linear, chaotic systems such as habitat, environment and climate, with a decline that has no single obvious cause and a total lack of scientific certainty, doing something at the margins is as unpredictable as doing nothing. This is not precautionary science.

At present, this basic question has been lost in the clamor “Do something at all costs” and to damn those who doubt if we can.