Environment Agency fisheries and operations delivery officers have been piling on the stones as part of a project to improve the Bray Mill Stream, near Maidenhead.

Mechanical diggers were called in to pour 600 tonnes of small stones and gravel over a 300-metre stretch of the stream creating the perfect breeding ground for fish as well as an ideal habitat for other wildlife to thrive.

The work, which took two weeks to complete, also involved cutting back trees to allow more light to reach the gravel bed to encourage plant growth.

Fish such as chub, dace and barbel need gravel beds to lay their eggs.

The gravel will restore the stream to a more natural flow pattern with areas of fast and slow moving water creating the necessary conditions required for the different life stages of fish.

The faster flow will ensure a constant supply of oxygenated water, helping develop the eggs, and once they hatch the gravel beds will provide a relatively safe nursery for the newly born fish fry to feed and grow.

The fish will then populate the River Thames just a few hundred metres downstream once they reach adulthood, and will return as adults to the stream to spawn.

Fisheries specialist Steve Sheridan said: “Our surveys of the Thames revealed a distinct lack of suitable gravel spawning habitat for species such as dace, chub and barbel in the area. This stretch of the Bray Mill Stream is an ideal location because it is so close to the Thames and is the right size with the perfect gradient.

“I’m delighted we’ve been able to complete this project as it will make a real difference to the diversity of wildlife for the whole area.”