Our fisheries experts have been assisting the Environment Agency with the identification of grey mullet fish species – the thick-lipped
mullet, thin-lipped mullet and golden grey mullet. Below a certain size, these three species are distinguishable only by ventral head pigmentation
patterns but are more difficult to identify until considerably larger.
We dissected each grey mullet specimen and examined pyloric caeca to identify each fish. Pyloric caeca are internal organs that resemble finger-like projections,
situated near the stomach and intestines. It is thought that their function is to aid digestion. Once located, pyloric caeca can be counted and lengths
analysed.
Rob Hillman, Senior Environmental Monitoring Officer from the Environment Agency said: “Correct identification is of paramount importance to our work at
the Environment Agency. We need to be absolutely certain of the identification on the species as it influences WFD (Water Framework Directive) estuary
fish classification scores. Thomson Unicomarine gave a quick turnaround on the project and provided us with the identifications, dissected specimens
and material that we can use as teaching aids.”
Thomson Unicomarine implements the NE Atlantic Marine Biological Analytical Quality Control Scheme (NMBAQC) for fish identification. Our team audits fish
monitoring laboratories around the UK and thereby aims to improve and maintain the standard of marine biological data being generated to assess the
status of marine waters in the UK and the North East Atlantic.