A citizen science program for brown treesnake removal and native species recovery at a National Historical Park in Guam
The National Park Service (NPS), U.S. Geological Survey (USGS), U.S. Fish and Wildlife Service (USFWS), and community Citizen Scientists are working together to remove brown treesnakes at War in the Pacific National Historical Park - Asan Beach Unit to aid restoration of native avian and reptile species.
NPS Brown Treesnake Control Website
Contact War in the Pacific National Park to Get Involved!
Invasive brown treesnakes in Guam
Brown treesnakes, an arboreal species native to Australia, Papa New Guinea, and Indonesia, were unintentionally introduced to the island of Guam in the 1940s. Since then, they have been linked to the extirpation of nine of the eleven native bird species on the island, and caused significant declines in other native bird, reptile, and bat populations. For these native wildlife populations to recover, brown treesnake populations need to be dramatically reduced or completely eradicated. In constructed snake enclosures in Guam, standard control tools like trapping and hand capture have been shown to successfully eradicate brown treesnakes in areas up to one hectare — that is, an area equivalent in size to 2.5 acres, two football fields side-by-side, or a large city block — and drastically reduce populations in areas up to five hectares.
Asan Beach Park – an ideal place to test invasive snake control methods
Asan Beach is a unit of the War in The Pacific National Historical Park in Guam and is managed by the National Park Service. The Park is a peninsula that sits along the Guam coast and is approximately 44 hectares. It consists of a large, grassy area lined with a forested ridge on the west side that can provide ideal habitat for native bird species. Asan Beach is naturally isolated by an ocean on one side and large road on the other, which could essentially form a natural, semi-permeable snake barrier. Thus, the site presents a unique opportunity to test brown treesnake suppression methods and bird restoration efforts in a protected area. So far, visual surveys along previously established trails have resulted in the detection of 47 snakes and hand-removal of 31 snakes between May and August 2024. However, there are likely hundreds more snakes that need to be trapped before wildlife restoration projects can begin. Future integrated snake control efforts will use various ground-based tools like hand capture from visual surveys, toxicant baits, and trapping with live lures.
Incorporating citizen science into brown treesnake control
While effective, trapping and hand capture control methods require lots of time and dedicated scientists who know how to find and trap snakes in the wild. For that reason, project leaders proposed recruiting citizen scientists — members of the public that voluntarily participate in scientific research — into brown treesnake control efforts. Three Department of Interior (DOI) agencies (NPS, USGS, and USFWS) are in the process of organizing a Citizen Science effort for the project. Ultimately, they seek to evaluate the effectiveness of 1) utilizing citizen science for brown treesnake removal, 2) semi-impermeable barriers to snake re-entry, 3) brown treesnake suppression in the face of complex habitat features (for example, cliffs), and 4) restoration of native species following significant brown treesnake suppression.
On Saturday, November 16, War in the Pacific National Historical Park staff are hosting a kickoff event to teach members of the community about the project and recruit citizen scientists. Stay tuned for more information on this event and how to get involved!
Invasive Species We Study: Brown Treesnake
Biology, Impacts and Control of Invasive Reptiles in the Pacific
The National Park Service (NPS), U.S. Geological Survey (USGS), U.S. Fish and Wildlife Service (USFWS), and community Citizen Scientists are working together to remove brown treesnakes at War in the Pacific National Historical Park - Asan Beach Unit to aid restoration of native avian and reptile species.
NPS Brown Treesnake Control Website
Contact War in the Pacific National Park to Get Involved!
Invasive brown treesnakes in Guam
Brown treesnakes, an arboreal species native to Australia, Papa New Guinea, and Indonesia, were unintentionally introduced to the island of Guam in the 1940s. Since then, they have been linked to the extirpation of nine of the eleven native bird species on the island, and caused significant declines in other native bird, reptile, and bat populations. For these native wildlife populations to recover, brown treesnake populations need to be dramatically reduced or completely eradicated. In constructed snake enclosures in Guam, standard control tools like trapping and hand capture have been shown to successfully eradicate brown treesnakes in areas up to one hectare — that is, an area equivalent in size to 2.5 acres, two football fields side-by-side, or a large city block — and drastically reduce populations in areas up to five hectares.
Asan Beach Park – an ideal place to test invasive snake control methods
Asan Beach is a unit of the War in The Pacific National Historical Park in Guam and is managed by the National Park Service. The Park is a peninsula that sits along the Guam coast and is approximately 44 hectares. It consists of a large, grassy area lined with a forested ridge on the west side that can provide ideal habitat for native bird species. Asan Beach is naturally isolated by an ocean on one side and large road on the other, which could essentially form a natural, semi-permeable snake barrier. Thus, the site presents a unique opportunity to test brown treesnake suppression methods and bird restoration efforts in a protected area. So far, visual surveys along previously established trails have resulted in the detection of 47 snakes and hand-removal of 31 snakes between May and August 2024. However, there are likely hundreds more snakes that need to be trapped before wildlife restoration projects can begin. Future integrated snake control efforts will use various ground-based tools like hand capture from visual surveys, toxicant baits, and trapping with live lures.
Incorporating citizen science into brown treesnake control
While effective, trapping and hand capture control methods require lots of time and dedicated scientists who know how to find and trap snakes in the wild. For that reason, project leaders proposed recruiting citizen scientists — members of the public that voluntarily participate in scientific research — into brown treesnake control efforts. Three Department of Interior (DOI) agencies (NPS, USGS, and USFWS) are in the process of organizing a Citizen Science effort for the project. Ultimately, they seek to evaluate the effectiveness of 1) utilizing citizen science for brown treesnake removal, 2) semi-impermeable barriers to snake re-entry, 3) brown treesnake suppression in the face of complex habitat features (for example, cliffs), and 4) restoration of native species following significant brown treesnake suppression.
On Saturday, November 16, War in the Pacific National Historical Park staff are hosting a kickoff event to teach members of the community about the project and recruit citizen scientists. Stay tuned for more information on this event and how to get involved!