Estimating spawning stock biomass using egg surveys

Information on using egg serveys to calculate spawning stock biomass has been added to the fisheries information section.

• Why do we carry out egg surveys?
• How do we sample planktonic eggs?
• Mapping egg distributions
• Estimating the average density of eggs in a survey, and the total abundance
• Converting to daily egg production using egg development rates
• The problem of egg identification
• Calculating seasonal egg production
• Calculating spawning stock biomass from annual egg production
• A worked example: Irish Sea plaice