Volunteers are trialling a project where temporary fences are put up around the threatened birds' nests in an attempt to protect them from other beach users and arrest their declining population.

Far West Friends of the Hooded Plover members were shocked this week to find signs made by Port Fairy students had been ripped off, the fence destroyed and the birds' shelters ruined by heartless vandals.

A replacement fence was pulled down on Wednesday.

"It is a sad day for our community when something as unthreatening as a child's drawing of a bird is torn down angrily when its sole purpose is to warn beach users of a small defenceless chick in the sand nearby," regional co-ordinator Toni Ryan said.

The breeding season had been encouraging, with a number of chicks reaching fledgling stage and a few nests still being incubated.

However, vandalism was risking damage to the eggs and the nesting process.

Dr Grainne Maguire, from Birds Australia, said the flightless chicks needed about 100 metres of undisturbed space to survive, which the fencing on Warrmambool and Killarney beaches aimed to create.

"It is a real shame that conservation efforts for these birds are so misunderstood," he said.

"It doesn't mean we all can't continue to use the beach but sadly some people must think this a step towards removing people or dogs or horses from the beach.

''It doesn't have to be that way if we can just respect the efforts of volunteers and kids and share the beach with these birds."

With South African marram grass taking over the sand dunes, rising tides and more recreational users, the hooded plover stood little chance of survival beaches without intervention, Dr Maguire said.