Manx Wildlife Trust is reminding dog walkers which wetland areas they can and can't take their pets.
Its message comes after its received reports of lots of dogs being at Cronk Y Bing and waste not being picked up there.
The trust says this can not only be unpleasant for visitors but can impact the delicate nutrient balance in the soils.
As a result, the organisation says Dalby Mountain, Earystane, Glen Dhoo and Onchan wetlands are the only MWT reserves which allow people to take their canines.
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