During the four-hour event they viewed captured small mammals, including mice and voles, and studied fungi including mushrooms and toadstools.

Adrian Hobbs, chairman of the Moor Green Lakes group of volunteers, said the reserve is only open to the public once a year to safeguard breeding sites.

He said: “Those attending were seeing creatures they had not seen before, and the pond dipping was very popular because there is so much wildlife in there.

“Also popular was the bug hunting and moss collections.” There were four walks, with a bird expert and recording equipment, to illustrate the many varieties of British birds of prey and foreign birds that visit the reserve.

Mr Hobbs said youngsters were fascinated by the many nesting boxes at the site and were interested in the system of 'ringing’ the chicks so that experts could track the birds’ journeys worldwide.