Cairngorms National Park Authority is asking for the public's help in protecting its fish, frogs and toads.
One of the new leaflets
It has produced two new leaflets giving details on how to spot and then report sightings of Japanese knotweed and North American signal crayfish.
The non-native species pose a danger to the park's native wildlife.
A second leaflet encourages park residents and visitors to record sightings of frogs, toads and newts which are under threat from disease.
The aggressive signal crayfish got into Scottish waters about 10 years ago and has been in England and Wales since the 1970s.
The predator, said to devour natural wildlife and wreck the ecosystem, has previously been spotted in Leithen Water in Borders.
Cairngorms biodiversity officer, Justin Prigmore, said: "We need as much assistance as possible from the public with both of these initiatives so please get involved."
The park already has a conservation officer dedicated to the ensuring the survival of water voles.