Why carry out a biological sampling programme?
Sampling throughout the year allows scientists to monitor differences in growth and age over the year, and gives information on the amount of fish removed from the stock. This information is collected through various sampling programmes and the data are used to provide advice on the sustainable management of fish stocks, upon which the industry depends.
How is the sampling programme implemented?
Length distributions of landed fish can be obtained from samples taken in the auction halls, ports, quays side sampling or at sea on commercial vessels. Generally, the length sampling is carried out by area, gear and time to ensure that the estimated size distribution is accurate.
In addition, Marine Institute scientists collect data on the age and weight-at-length from these samples. Fish are ‘aged’ to give an indication of the health of the stock. A broad range of ages signifies a healthy stock; a lack of young fish could mean poor spawning in a particular year; a lack of older fish may signify overfishing.
Achieved sampling can be seen in the Irelands Data Collection Framework Annual Report for the relevant years.