Melia G. Nafus Patrick D. Barnhart Aaron F. Collins Scott M. Goetz Charlene Hopkins Page E. Klug Gordon Rodda Marijoy Viernes Amy Yackel Adams 20240520 tabular digital data https://doi.org/10.5066/P93K6LG5 Melia G. Nafus Levi N. Gray Page E. Klug Gordon H. Rodda Scott M. Goetz 20250401 publication Wildlife Research vol. 52, issue 4 n/a CSIRO Publishing https://doi.org/10.1071/WR24085 These data were collected as part of several studies or efforts to remove brown treesnakes (Boiga irregularis) across three sites located in Guam, USA and one site in Cocos Island (Dano), Guam, USA. The various goals of projects were distinct and these data were applied to a more intensive, cross site comparison on the height snakes were detected during visual surveys as a function of their size or body condition. The appropriate use of these data relate to comparing the size or condition of snakes to their general perch height at the time of detection. 20060104 20230316 observed Complete None planned Guam 144.6300 144.9500 13.6500 13.2300 ISO 19115 Topic Category biota None Arboreal behavior condition size USGS Metadata Identifier USGS:6539e335d34ee4b6e05bbd21 None Guam Cocos Island, Guam None Boiga irregularis Brown Treesnake Kingdom Animalia Subkingdom Bilateria Infrakingdom Deuterostomia Phylum Chordata Subphylum Vertebrata Infraphylum Gnathostomata Superclass Tetrapoda Class Reptilia Order Squamata Suborder Serpentes Infraorder Alethinophidia Family Colubridae Subfamily Colubrinae Genus Boiga Species Boiga irregularis TSN: 174206 None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Melia G. Nafus U.S. Geological Survey, NW-PACIFIC ISLAND REG Research Ecologist mailing address

Bldg 344 Chain of Craters Rd.

Hawaii Natl Park HI 96718 US 970-413-2878 808-967-8568 mnafus@usgs.gov Depart of Interior, Office of Insular Affairs and Department of the Navy, Joint Region Marianas (IAA #N61128-20140529-0001) provided funding the support the data collection. Microsoft These data represent actual values collected from individual snakes by human observers. The values fall within expected values The data are site or temporally specific information related to the height at which snakes were located relative to their size or body condition NA NA Melia G Nafus Aaron F Collins Marijoy C Viernes Charlene B Hopkins Amn Michael G Nacpil 2023 dataset https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/p9qrwkqb Digital and/or Hardcopy 2023 publication date Nafus et al. 2023 Data United States Geological Survey 2023 dataset https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/p9mt1jno Digital and/or Hardcopy 2020 publication date USGS 2023 Data GORDON H. RODDA JULIE A. SAVIDGE CLAUDINE L. TYRRELL MICHELLE T. CHRISTY AARON R. ELLINGSON 20101213 publication The Journal of Wildlife Management vol. 71, issue 2 n/a Wiley ppg. 656-661 https://doi.org/10.2193/2005-742 Digital and/or Hardcopy 2007 publication date Rodda et al. 2007 Description of data collection methods Melia G. Nafus Amanda Reyes Thomas Fies Scott M. Goetz 20240219 publication Journal of Applied Ecology vol. 61, issue 4 n/a Wiley ppg. 733-745 https://doi.org/10.1111/1365-2664.14597 Digital and/or Hardcopy 2024 publication date Nafus et al. 2024 Description of data methods Melia G. Nafus Shane R. Siers Brenna A. Levine Zachary C. Quiogue Amy A. Yackel Adams 20211228 publication The Journal of Wildlife Management vol. 86, issue 1 n/a Wiley https://doi.org/10.1002/jwmg.22136 Digital and/or Hardcopy 2022 publication date Nafus et al. 2022 Methods description for data Data were collected by completing nocturnal visual surveys by trained human observers with high powered headlamps. When surveyors detected a snake they documented the visually estimated height in meters of the snake. Each observer was trained to estimate height of snakes by using standard objects of known meter lengths (such as a snake handling pole) and counting the number required to reach the snake. Afterwards, observers captured the snake and processed it by collecting morphometric data. Those data included the snake's snout vent length (SVL) in millimeters (mm) as a function of using a measuring tape to measure the length from the tip of the snout to the vent. Observers also measured the weight of the snake in grams (g). From these two data sets the condition index ratio was calculated as a function of log weight to expected weight (the average weight of the entire sample population) ratios. Each snake was assigned a unique identification number to ensure that every snake was only represented a single time in the data set even for sites in which there were multiple captures for each individual. Work was completed at four study sites as described below. Andersen Air Force Base (AAFB) Andersen Air Force Base housing (AAFB, Guam, USA; 13.561 degrees N, 144.923 degrees E) is ~105 ha in a periurban, residential neighborhood in northeast Guam. We collected data on AAFB brown treesnakes occurred from December 2019-August 2022, with 352 individuals captured. We visually searched for brown treesnakes, starting approximately 30 min after sundown using a high-lumen headlamp (Lupine Lighting Systems, Wilma R X14). A single observer collected all data on prey and snakes with surveys focused on individual trees. Each tree was allocated an approximately 2 min search time. While surveying a given tree, we also counted each lizard, bird, or small mammal observed and used those data to estimate prey sightings per hour of survey. We stopped time when we observed a snake to record the approximate height based on visual estimation to at least 0.5-m intervals. Accuracy and precision of height estimates tended to decrease as distance increased. We then attempted to capture the snake by hand. We morphologically processed captured snakes (see above section) and then released them at the point of capture. Cocos Island (DANO) Cocos Island (DANO) is a ~33 ha island. DANO is dominated by coastal strand forest on sand substrate. Limited limestone karst substrate exists in association with the southern shore. Research and data collection on brown treesnakes in DANO occurred from October 2020-September 2021, with 55 total snakes captured during this period. We visually searched for brown treesnakes along 31 transects that were ~400-m each, starting approximately 30 min after sundown. We collected all data on prey and snakes in teams of two, with each observer searching in a single direction using a high-lumen headlamp (Lupine Lighting Systems, Wilma R X14). Each transect survey required approximately 60 minutes. On average individuals searched approximately three transects per night. Initially, we rotated nightly transect assignments to ensure approximately equal coverage across the island. In July 2021, after determining we were not finding snakes on six of the transects, we adjusted transect assignments to focus more intensively on areas with greater captures. When a snake was seen, we stopped time and recorded the approximate height based on visual estimation of 0.5-m intervals and then attempted to capture the snake. In addition to capturing snakes by hand, we also shot them with 0.39 g plastic pellets fired from airsoft electric gun air rifles to prevent escape. We placed captured snakes in a cloth snake bag and proceeded with surveys. Each snake was morphometrically processed at the laboratory the next day (see above) and then euthanized. During each transect, we also counted each lizard, bird, or small mammal observed to the level of species when identifiable. Habitat Management Unit (HMU) The Habitat Management Unit (HMU, Guam, USA; 13.596 degrees N, 144.865 degrees E) is a 55-ha snake exclosure built in 2010 for conservation purposes. Research and data collection on brown treesnakes at the HMU occurred from March-August 2013, with 199 snakes detected. Visual surveys followed similar protocols as described for DANO, with 17 transects of ~470-m in length. We completed each transect survey in approximately 30 min. When a snake was observed, as with other projects, we stopped time, recorded the canopy height, and attempted hand capture. We also recorded all lizard, birds, or small mammals observed during surveys. North West Field North (NWFN) North West Field North (NWFN, Guam, USA; 13.640 degrees N, 144.865 degrees E) is a 5-ha fenced area also located in northern Guam, used to study brown treesnakes. This site has been the focus on long-term research on brown treesnakes and thus data collection occurred on and off from 2006-2023, with 398 individuals detected. The full process of visual surveys and field efforts at this site are well described in prior publications (Rodda et al. 2007, Nafus et al. 2022, Nafus et al. 2024). Briefly, however, in October 2006-December 2007 and from October 2016-March 2017, we censused the population by conducting surveys 1-4 nights per week. Pacing for 2006-2007 surveys was 30 min per 220-m transect. In 2016, we decreased the per transect survey time to 10-min per 220-m transect. Visual survey and snake capture protocols followed those already described for DANO and HMU. On 31 March 2017, we began an intensive snake removal effort which is described in previously published work (Nafus et al. 2022, Nafus et al. 2023, Nafus et al. 2024). Briefly, we removed snakes using toxic mouse carrion from 31 March 2017-20 September 2021. During 14 September 2020-25 October 2021, we added chick and rat carrion as baits. During 01 March 2021-23 December 2021, we started removing snakes using traps that had live mouse or bird lures. From 24 October 2016-31 March 2023, we also removed any snakes captured by hand. After we began euthanizing snakes, we first completed morphometric processing. Throughout this period, the snake population experienced a continuous decline in numbers other than a brief birth pulse (Nafus et al. 2024). The full data from 2016-2023 with detailed descriptions of snake removal methods are available for download (Nafus et al. 2023). Nafus et al. 2023 USGS 2023 Rodda et al. 2007 Nafus et al. 2022 Nafus et al. 2024 20220131 BTS Arboreality Dataset.xlsx (Sheet1) Excel Worksheet Producer Defined PITTAG A unique identifier for each snake based on a random series of letters and numbers. Producer Defined The values are a random sequence of numbers or letters to identify individual snakes. DATE The date that the data were collected represented as DD-MMM-YY Producer Defined 04 January 2006 16 March 2023 SVL The snout to vent length of each individual snake Producer Defined 288 1989 millimeters WEIGHT The weight in grams of each individual snake. Producer Defined 4 1122 grams Cond The condition score of each individual as calculated by taking the log of its weight and dividing that by the log of the expected weight based on the sampled population. Producer Defined 0.3108 1.5016 log ratio PREY The number of prey counted per hour of nocturnal visual surveys during the survey period at each site for each snake size. Producer Defined 0.03 31.33 prey per hour HGT The height at which each snake was located as estimated from a human observer standing on the ground. Estimated height was done at the level of precision for which an observer was comfortable and generally become less resolute as the distance increased. Producer Defined NA Height was not recorded for that specimen. Producer defined 0.0 16.0 meters Site The location by site code or time period for which each snake was collected. Producer Defined NWFN21 Defined as Northwest Field North and characterized as a 5-ha snake enclosure located in northern Guam. Data in this category pertain to snakes that were captured in September 2021 - May 2022. Producer defined DANO Data pertaining to snakes captured on a small island off the southern shore of Guam. Producer defined HMU Data pertaining to snakes captured in the Habitat Management Unit, which is a 55 ha snake exclusion area located on Andersen Air Force Base, northern Guam. Producer defined AAFB Data pertaining to snakes captured in military housing located on Andersen Air Force Base on Northern Guam. Producer defined NWFN07 Defined as Northwest Field North and characterized as a 5-ha snake enclosure located in northern Guam. Data in this field pertain to snakes that were captured in 2006 - 2007. Producer defined NWFN19 Defined as Northwest Field North and characterized as a 5-ha snake enclosure located in northern Guam. Data in this field pertain to snakes that were captured in 2019. Producer defined NWFN16 Defined as Northwest Field North and characterized as a 5-ha snake enclosure located in northern Guam. Data in this field pertain to snakes that were captured in October 2016 - March 2017. Producer defined NWFN22 Defined as Northwest Field North and characterized as a 5-ha snake enclosure located in northern Guam. Data in this field pertain to snakes that were captured in after May 2022. Producer defined Design Classification as to whether the study was purely observational or manipulative Producer Defined Observational The authors intent was not to manipulate the snake population over several years and counted snakes that were present. Producer defined Manipulative The study measured changes in a site over several years as snakes were removed and prey counts changed in response. Producer defined GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Digital Data https://doi.org/10.5066/P93K6LG5 None 20250808 Data Steward U.S. Geological Survey, NW-PACIFIC ISLAND REG mailing address

Bldg 344 Chain of Craters Rd.

Hawaii Natl Park HI 96718 US 808-905-6420 808-967-8568 pierc-datasteward@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999