Published: 08:00, 30 July 2014 |
Karen Groombridge, from Milton Regis, found a handful of empty gas gun shells at a nearby lake popular with children and anglers.
She found the spent canisters on the banks of the water off Newman Drive, in Kemsley, before a junior fishing contest.
The 52-year-old, Kingsmill Close, said she is convinced the ammunition was used against a family of moorhens - regular visitors to the lake.
She said: "I'm praying the birds haven't been killed and by putting this in the public domain I'm hoping it will deter these people from coming back.
"To me, it's obvious someone is trying to kill wildlife for fun as some sort of sick pastime.
"These people are idiots and we've been onto police a number of times about similar incidents."
Ms Groombridge said she discovered 10 canisters on Sunday morning between the lake's two fishing platforms.
She said three adult moorhens and "half-a-dozen babies" are among wildlife which gathers at the water.
Although no dead birds have so far been discovered, she claims only one adult and one baby has been seen since the shells were found.
Grandmother-of-four Ms Groombridge is vice chairman of Kemsley Community Angling Preservation Society which organised the junior fishing contest.
She believes the guns were fired sometime between Friday night and Sunday morning as there was no sign of the cases during a community clean-up of the lake before the weekend.
She said: "Like a lot of parents, I like to bring my family to the lake. The truth is, we always have this trouble at the beginning of the school holidays.
"I would ask people living by the lake to be more vigilant and phone police if they see anyone with guns."
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