We deployed 30 trap stations consisting of three combinations: isolated bird-lure traps, isolated mouse-lure traps, or paired stations to evaluate snake capture as a function of lure. At the paired stations, we included two traps: one bird-lure trap and one mouse-lure trap. All stations were at least 60 meters (m) apart and each of the station treatments was replicated 10 times. Traps at paired stations ranged from 1.7 to 6.7 m apart (mean 3.22 ± 0.46) depending on availability of vegetation from which to suspend traps. Both mouse-lure traps and bird-lure traps were adapted from standard modified commercial minnow traps composed of 6 millimeter (mm) galvanized steel mesh. The traps were operational for 67 trap nights to get a time trend as refuse odor accumulated in and under the trap and to evaluate trap efficacy as the Brown Treesnake (BTS) population was suppressed. Traps were checked every 48 to 72 hours for a total of 29 trap checks. Trap stations were located on Guam National Wildlife Refuge outside of the BTS exclosure fence. We used three areas outside of the snake exclosure with balanced station treatments at each site. The habitat was mainly limestone forest.

Manually photo-processed remote camera trap data of Brown Treesnakes on Guam at snake traps with live mouse lures. Records of snakes entering the field of view (FOV) and exiting the FOV by day, time, and trap location. Photos were further processed to retain only detections of snakes up to 1.83 meters from the camera, i.e., only records of snakes that were on or in front of the mouse-lure trap are retained in the data file.

Manually photo-processed remote camera trap data of Brown Treesnakes on Guam at snake traps with live mouse lures. Records of snakes entering the field of view (FOV) and exiting the FOV by day, time, and trap location. Photos were further processed to retain only detections of snakes up to 1.83 meters from the camera, i.e., only records of snakes that were on or in front of the mouse-lure trap are retained in the data file.

Over a 22-week period both with and without active Brown Treesnake (BTS) snake removal, we evaluated snake-trap contact rates at mouse- and bird-lure traps within the Guam National Wildlife Refuge in 2014. Bird-lure traps served as a proxy for reintroduced nesting birds. Data consists of 3 files generated from camera surveillance and trapping using mouse and bird lures in conventional snake traps on a 6 x 18 trapping grid. Trap survey effort contains summary results for a set of traps on a single occasion. Mark release data consist of individual capture records of trapped snakes. Camera transcription consist of animals detected via motion and time-lapsed photography at traps using bird lures.

Over a 22-week period both with and without active Brown Treesnake (BTS) snake removal, we evaluated snake-trap contact rates at mouse- and bird-lure traps within the Guam National Wildlife Refuge in 2014. Bird-lure traps served as a proxy for reintroduced nesting birds. Data consists of 3 files generated from camera surveillance and trapping using mouse and bird lures in conventional snake traps on a 6 x 18 trapping grid. Trap survey effort contains summary results for a set of traps on a single occasion. Mark release data consist of individual capture records of trapped snakes. Camera transcription consist of animals detected via motion and time-lapsed photography at traps using bird lures.

Data were collected in association with locations of standard brown treesnake traps on Guam at location prior to suppression or control efforts and after control had occurred. In all cases study sites were closed or semi-closed populations of brown treesnakes. Habitat data focused on type and structure of the habitat within 10-m of the trap.

Data were collected in association with locations of standard brown treesnake traps on Guam at location prior to suppression or control efforts and after control had occurred. In all cases study sites were closed or semi-closed populations of brown treesnakes. Habitat data focused on type and structure of the habitat within 10-m of the trap.

Nocturnal visual encounter surveys for Brown Treesnakes were collected and summarized into 4 plain text files (csv format): CapturesLure, SurveysLure, CapturesScent, and SurveysScent. Capture files contain unique Passive Integrated Transponder (PIT) tag identification and measurements of snakes with dates and locations of capture. Survey files contain the dates of transect sampling and treatment application for each transect (Transect ID). Each project used a different type of attractant, either a live-mouse lures in snake traps or liquid fish fertilizer scented spray. Surveys were conducted in a 5-ha geographically closed population on Guam. Teams of two observers conducted night-time surveys from February 1 to March 31 2015 (live-mouse lure project) and November 1 to December 30 2016 (spray scent project). Visual surveys occurred along maintained 220-meter long transects at 8 meter spacing. Observers used headlamps to search for snakes in the vegetation or on the ground. Observers recorded snake identification, measurements, capture location, and date. Surveys began 30 minutes after sunset. For the lure study, transects either had no traps and live mouse lures (NTL) placed on them or had snake traps with live mouse lures (TL). Snake traps were modified minnow traps. Traps were suspended horizontally from natural vegetation 1-1.5 meter (m) off the ground. Within each trap, a chamber housed and protected a live-mouse attractant. Traps were deployed along the same transects where nocturnal visual surveys occurred. For the spray scent study, transects were either unsprayed (1) or sprayed either in the early evening before the night-time survey (2) or the previous day (3). Spray scent consisted of 500 milliliters of Alaska Fish Fertilizer and 14.74 liters of water and was sprayed along the entire length of a transect using a spray backpack over the course of four minutes to ensure a consistent application rate. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Nocturnal visual encounter surveys for Brown Treesnakes were collected and summarized into 4 plain text files (csv format): CapturesLure, SurveysLure, CapturesScent, and SurveysScent. Capture files contain unique Passive Integrated Transponder (PIT) tag identification and measurements of snakes with dates and locations of capture. Survey files contain the dates of transect sampling and treatment application for each transect (Transect ID). Each project used a different type of attractant, either a live-mouse lures in snake traps or liquid fish fertilizer scented spray. Surveys were conducted in a 5-ha geographically closed population on Guam. Teams of two observers conducted night-time surveys from February 1 to March 31 2015 (live-mouse lure project) and November 1 to December 30 2016 (spray scent project). Visual surveys occurred along maintained 220-meter long transects at 8 meter spacing. Observers used headlamps to search for snakes in the vegetation or on the ground. Observers recorded snake identification, measurements, capture location, and date. Surveys began 30 minutes after sunset. For the lure study, transects either had no traps and live mouse lures (NTL) placed on them or had snake traps with live mouse lures (TL). Snake traps were modified minnow traps. Traps were suspended horizontally from natural vegetation 1-1.5 meter (m) off the ground. Within each trap, a chamber housed and protected a live-mouse attractant. Traps were deployed along the same transects where nocturnal visual surveys occurred. For the spray scent study, transects were either unsprayed (1) or sprayed either in the early evening before the night-time survey (2) or the previous day (3). Spray scent consisted of 500 milliliters of Alaska Fish Fertilizer and 14.74 liters of water and was sprayed along the entire length of a transect using a spray backpack over the course of four minutes to ensure a consistent application rate. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

These data represent brown treesnake (Boiga irregularis) captures from a population in a 5 ha natural snake enclosure on Guam from 2016 - 2023. During the period of study we artificially reduced the number of snakes present in the population through a variety of control tools that included toxic baits, as mice and chicks, live trapping, and hand capture. We censused the population intensively during the entire period of study during nocturnal visual surveys. During those surveys we also counted the number of lizards, rodents, and birds that were seen. Thus, we have absolute numbers of snakes based on mark-recapture methods and capture-per-unit-effort based on sightings of all taxonomic groups. These data are specifically processed to provide monthly estimates of numbers of brown treesnakes relative to the average sightings per unit effort of rodents, lizards, and birds. Brown treesnakes are an invasive species that has had detrimental impacts on almost all native vertebrate on Guam. Raw data used to generate estimates are available in an affiliated data release.