Residents are asked to report any sightings of Pacific Pink Salmon in the Island's rivers this summer.
The Manx government says its due to the potential risk the invasive species poses to native wildlife.
The fish can be identified by large black oval spots on its tail, a very dark mouth and tongue, with smaller scales than Atlantic Salmon.
The only previous sighting in a Manx river was in 2021, and experts believe the species is likely to return this summer due to its two year spawn cycle.
Anglers are asked to remain vigilant and report any sightings to FisheriesEnquiries.DEFA@gov.im
Weather warning for storm Dave this weekend
Roads to close for music festival this weekend
How long do mental health patients stay in Manannan Court?
Could you take over this former restaurant?
Framework of new Sea Services Agreement ready, says minister
Attorney General says he's stepping down
Road closures in two towns for running event this week
Six weekend ferry crossings could face disruption