Repeated mowing of the grass on marsh land is killing off wildlife, according to a campaign group.

Save Lea Marshes (SLM) says the grass was cut “savagely” last week, leaving the area “baron and lifeless.”

The group, which campaigns to preserve areas including Walthamstow and Leyton Marshes, believes the grass should not be cut down to the ground because it kills wildlife living in the grass, which impacts on bigger animals and birds.

Caroline Day of SLM said: “If you mow grass to the ground you destroy everything that lives in that area at that time and you destroy the eco-system.

“It all impacts up the food chain so there’ll be less birds because there won’t be anything for them to live off.

“It will have a really big impact on the wildlife in that area.”

The marshes are home to a range of wildlife and plant species including a thriving population of the rare and endangered water vole, butterflies, dragonflies, birds, reptiles, amphibians and mammals.

SLM said a London Wildlife Trust survey, commissioned by the Lea Valley Regional Park Authority (LVRPA) this year recommended that the grass should be left at a minimum of 10cm in length.

The group suggest the authority use grazing cattle on the land instead to do their grass cutting.

A spokeswoman for LVRPA said the marshes are managed in accordance with their agreement with Natural England and that they are still reviewing the report by the London Wildlife Trust to guide their future management of the area.

She said:“Management of the biodiversity and conservation value of the sites is a key priority for LVRPA.

“Traditional land management methods are used where possible and we have a conservation grazing, meadow and woodland management programme in place to protect and enhance the biodiversity of the park.

“Regular monitoring of key species and habitats on the marshes provide the Authority with the a clear understanding of what is present on site, allows us to measure the success of our management and tailor future management accordingly.”