Northern Ireland National Imposex Surveys

The DAERA Northern Ireland National Imposex Survey is a tri-annual (once every three years) assessment of the bio-effect of Tri-Butyl-Tin (TBT) on the dog whelk Nucella lapillus. Data is collected for the purposes of reporting to the EU Water Framework Directive (WFD), the EU Marine Strategy Framework Directive (MSFD), the Clean Safe Seas Evidence Group (CSSEG), and the OSPAR Commission.

Data and Resources

Additional Info

Field Value
Creation Date December 7, 2018, 11:20 (UTC)
Topic Category
  • Biota
  • Environment
  • Oceans
Lineage

Samples are collected onshore by trained field staff. Specimens are transferred to the laboratory and stored in oxygenated tanks for no more than 48 hours prior to dissection. Vas Deferens Stage (VDS) categories are assessed using groupings described in Gibbs, P.E., Bryan, G.W., Pascoe, P.L. and Burt, G.R., 1987. The use of the dogwhelk Nucella lapillus as an indicator of tributyltin (TBT) contamination. J. Mar. Biol. Ass. UK 67:507-523. Male and female (if penis present) penis lengths are measured in millimetres for use in calculation of the Relative Penis Size Index (RPSI). Data quality is assured by participation in the QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe) scheme. Participant laboratories are sent sub-samples from the same population, and returned values must fall within accepted standard error limits for the entire community.

Frequency of Update Irregular
Contact Name Data contact
Contact Email marine.inforequests@daera-ni.gov.uk
Additional Information
Visibility False