The increasing numbers of invader species, like the voracious northern snakehead fish, have given environmental officials a fright. WNYC's Ilya Marritz reports state regulators are now working on a plan to curb foreign plants and animals.

REPORTER: According to Steve Sanford of the Department of Environmental Conservation, even innocent-looking flowers can cause problems like the purple loosestrife.

SANFORD: It's a beautiful plant. It's tall, showy, a spike flower that flowers throughout the summer with a beautiful magenta blossom on it.

REPORTER: but Sanford says,

SANFORD: It is a very aggressive weed in wetland communities and it can release chemicals from its roots that actually prohibit the development and growth of things like frogs and salamanders.

REPORTER: Now Albany is proposing to classify non-native species as either “prohibited,” “regulated” or “unregulated," depending on the threat they pose to the ecosystem. Sanford says if it's adopted, the plan will give regulators the power to anticipate the next threat rather than play catch-up.