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Brown Tree Snake

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Brown Tree Snake
Scientific Name:
Boiga irregularis (Merrem, 1802) (ITIS)
Common Name:
Brown tree snake (BTS)
Brown Tree Snake, The "cat eyes" appearance is a distinguishing characteristic. Photo by Gordon Rodda; DOI, United States Geological Survey


Native To:
Australia, Indonesia, Papua New Guinea (Colvin et al. 2005)
Date of U.S. Introduction:
First detected in Guam in the 1950s (Colvin et al. 2005)
Means of Introduction:
Likely arrived in Guam accidentally in imported cargo (Colvin et al. 2005)
Preys on native lizards and birds (Colvin et al. 2005); causes frequent power outages by climbing on electrical wires (Colvin et al. 2005)
Current U.S. Distribution:
Guam; not currently established in the continental U.S.

Federally Regulated

  • DOI. FWS. Fish and Aquatic Conservation.

    Includes species listed as injurious wildlife under the Federal Lacey Act (18 USC 42), which makes it illegal to import injurious wildlife into the United States or transport between the listed jurisdictions in the shipment clause (the continental United States, the District of Columbia, Hawaii, the Commonwealth of Puerto Rico, and any possession of the United States) without a permit. An injurious wildlife listing would not prohibit intrastate transport or possession of that species within a State where those activities are not prohibited by the State.

    Injurious wildlife are wild mammals, wild birds, amphibians, reptiles, fishes, crustaceans, mollusks and their offspring or eggs that are injurious to the interests of human beings, agriculture, horticulture, forestry, wildlife or wildlife resources of the U.S. Plants and organisms other than those stated above cannot be listed as injurious wildlife.
    See also: Injurious Wildlife: A Summary of the Injurious Provisions of the Lacey Act (Dec 2017; PDF | 401 KB)



Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Brown Tree Snake.

Council or Task Force

Aquatic Nuisance Species Task Force.
Hawaii Invasive Species Council.


IUCN. Species Survival Commission. Invasive Species Specialist Group.

Federal Government

USDA. APHIS. National Wildlife Research Center.

State and Local Government

Commonwealth of Northern Mariana Islands. Division of Fish and Wildlife.
Hawaii Department of Agriculture.


Columbia University. Center for Environmental Research and Conservation.