MADISON, Wis. – The Wisconsin Department of Natural Resources today announced that revisions to Wisconsin’s Invasive Species Identification, Classification and Control Rule (ch. NR 40, Wis. Admin. Code) will become effective Jan. 1, 2027.
Ch. NR 40 makes it unlawful to transport, transfer, introduce, and in some cases, possess regulated invasive species. Invasive species are organisms that are nonnative and cause harm to Wisconsin’s environment, economy or may pose threats to human health.
This revision clarifies key sections and updates the species classified under the rule. Under ch. NR 40, invasive species are classified into two categories: prohibited or restricted.
Prohibited species are those that are not yet present in the state or may exist in small, isolated populations. Statewide containment is still feasible for species in the prohibited category. The rule makes it unlawful to transport, transfer, introduce or possess these species.
Restricted species are those that are already widespread in the state, and statewide containment is no longer feasible. The rule makes it unlawful to transport, transfer or introduce these species but does not regulate their possession. The aim of this classification is to prevent further introductions and spread.
A total of 65 new regulated species will be added to the rule, and 22 will be removed. An additional 46 species that are currently regulated will have their classification amended.
To help clarify these revisions, the DNR has created a summary of changes to species regulations. To view all changes to the rule, including revisions to sections beyond the species classifications, review the board order (beginning page 27) or the Rule Revision Guide. All information related to this rule revision, including recordings of presentations and important dates, can be found on the DNR website.
