Migrating Somerset eels tracked by camera
A high-tech camera is being used to track eels as they begin their migration to the North Atlantic from Somerset.
The acoustic camera has been placed in the Huntspill River to record the number of eels setting off on the 3,000 mile (4.800km) journey to the Sargasso Sea.
Scientists had previously been unable to record eel numbers, the Environment Agency said.
The cameras, which operate by using sound waves, were originally designed to detect cracks on oil rigs.
Environment Agency spokesman Pete Sibley said the introduction of the technology was "our first real chance to record and capture eel numbers by direct observation and increase our understanding of the creature's mysterious life cycle".
The eel population has suffered a 95% decline over the past 30 years as a result of over fishing, pollution and disease, the agency said.