An environmental campaigner said that unbridled growth in sea tourism could cost Isle of Man its conservation status.
The government is keen to expand Island's appeal to cruise visitors, but concerns are raised over the level of harmful emissions cruise ships can create.
In 2016 Isle of Man was announced a UNESCO Biosphere reserve. It is the only entire nation in the world earning the title.
However, Pete Christian from "Friends of the Earth" said greater importance needed to be placed on the environment in case that is to continue.