The Canal and River Trust are urging people in Lancaster and Morecambe to feed ducks with natural treats like oats, corn or defrosted peas instead of bread.
As spring approaches the Trust is calling on duck-feeders to make a few simple changes to how they feed their feathered friends.
The trust explains uneaten soggy bread can cause a build-up of bad nutrients which can lead to greater algae growth, spread disease and encourage pests such as rats.
Last year 78 per cent of people in Lancashire fed the ducks, 82 per cent of them admitting to feeding ducks with bread.
Becki Anderson, senior ecologist for the Canal & River Trust, said: “Please come and feed the ducks but do it sensibly so your children and future generations can enjoy it too.
“Bread’s not great for a duck’s health as it’s nothing like their natural diet so don’t over feed them with large quantities of it. “Try to vary what you give them and swap it for healthier more natural treats like oats, corn or defrosted frozen peas.
“Don’t follow the crowds, spread the love, and visit a new family of ducks to prevent large quantities of the starchy duck ‘junk food’ from clogging up the same places and potentially damaging the environment.”
The charity, which provides an important home to hundreds of thousands of ducks, said throwing bread can create overcrowding of bird populations.
The birds will then flock to the same location in search of their starchy treat.
Too many ducks or waterfowl in one place can stress the birds and lead to their habitats being damaged.
For more information on the campaign visit www.canalrivertrust.org.uk/duck