The Isles of Scilly Wildlife Trust has asked islanders to please stop removing sluice boards from Lower Moors.
The planks of wood are put in place to help monitor the wetlands and to stop saltwater seeping in during high tides, which can affect the water quality and ecology of the site.
Nikki Banfield told Radio Scilly that the sluice boards are working well.
"We’ve been doing lots of hydrology work with some visiting hydrologists across the moors checking the water quality and the sluice boards are actually working. They’re stopping a certain amount of saltwater going up through the moors. So in theory our drinking water should be a lot better quality as well. So it’s a win win all round."
However, she acknowledged that some people don’t like or don’t understand the use of sluice boards.
"There are concerns about the fact that there are mullet and eels going up into Lower Moors to spawn and to breed. But the sluice boards are checked daily, they’re not in place for extended periods of time. Our head ranger is there constantly monitoring what is going on, whether they need to be in place or not. He’s obviously keeping an eye out for wildlife and things like that as well.
"We’re also investing quite heavily in surveying and monitoring work as well and whenever the boards are removed it’s actually having an impact on that.”
Nikki added: “So please please please - you might not approve or agree with what is happening, but do not take it upon yourselves to remove the sluice boards."