HUNDREDS of critically-endangered eels have been discovered at the bottom of a reservoir near Bromsgrove.

Engineers found more than 500 of the fish in the last few inches of water at Hopwood's Upper Bittell Reservoir, while draining 12million baths from the site ahead of major repair works.

Carl Nicholls, Canal and River Trust fisheries manager, said: "It’s an unbelievable find really. Repairing Bittell Reservoir is a huge job and we’ve spent a few weeks rehoming tens of thousands of fish to other waterways.

"Just as the final few inches of water were draining out, we made this discovery.

"In 20 years working with fish I’ve never seen or heard of this many eels in one place before. In most fish rescues like this we might come across one or two, a couple of dozen maximum, but this was unreal."

With the help of MEM Fisheries, each eel was removed by hand and rehomed in the local Worcester & Birmingham Canal, which should provide ideal habitat for them to mature and grow.

While not uncommon in Britain's waterways, eels are rarely found in such high numbers, due to their population dropping by more than 90 per cent since the 1970s.

According to the International Union for Conservation of Nature, this puts them at greater risk of extinction than the giant panda.

The Canal and River Trust is investing more than £1million to repair Upper Bittell Reservoir this winter, including valves and piping which feed the local canal network.

For more information visit canalrivertrust.org.uk.