Melia G. Nafus Marijoy C. Viernes 20250602 tabular digital data https://doi.org/10.5066/P13JFSPU These data were created in October 2023 while completing nocturnal visual surveys for brown treesnakes (Boiga irregularis) as part of an early detection and rapid response training exercise. They contain data on counts of lizards, small mammals, and birds documented while completing surveys. There are no brown treesnake counts because no snakes were detected during the exercise. These data were collected as part of an early detection and rapid response exercise in Saipan. The appropriate use of the data is limited to estimating presence of species during visual surveys as limited by distance surveyed. 20231016 20231030 observed Complete None planned 145.6849 145.8408 15.2921 15.0920 Saipan ISO 19115 Topic Category biota None Early detection and rapid response Visual survey USGS Metadata Identifier USGS:68126a00d4be02416e14870b None Saipan No access constraints. Please see 'Distribution Information' for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Melia G Nafus USGS - NW-PACIFIC ISLAND REG Research Ecologist mailing and physical

PIERC - Kilauea Field Station,PIERC Office Bldg 344

Hawaii Natl Park HI 96718 808-210-4918 mnafus@usgs.gov U.S. Office of Insular Affairs funded the work and the Commonwealth of the Northern Mariana Islands Department of Natural Resources and U.S. Fish and Wildlife Service helped collect the dataset. Microsoft Office The dataset was checked to ensure that values were consistent and within expected ranges. Each data sheet was proofed within 72 hrs of being added to the database. The data match with the details provided and fall within the expected ranges. All duplicated data have been removed. The data pertain to surveys in Saipan only. A formal accuracy assessment of the vertical positional information in the data set has not been conducted or is not applicable. A formal accuracy assessment of the vertical positional information in the data set has not been conducted or is not applicable. We completed visual surveys in Saipan at two ports of entry, a Marina for private vessels (Seaport: 15º12ꞌ N, 145º46ꞌ E) and two sites adjacent to the airport (North: 15º6′ N, 145º43ꞌ; West: 15º7′ N, 145º43ꞌ E). We selected biosurveillance sites based on their proximity to vessels that arrive directly from Guam and credible brown treesnake sightings that had occurred in adjacent areas in the last decade. Seaport habitat was primarily disturbed coastal strand dominated by Hibiscus tiliaceus, ironwood (Casuarina equisetifolia), coconut palm (Cocos nucifera) and other miscellaneous tree species. Airport habitat was primarily disturbed limestone forest, which was dominated by Leucaena leucocephala, Albizia spp., and flame trees (Delonix regia). We established all transects along current or historical (overgrown but traversable) roadsides at the edge of forest. We completed visual surveys in Saipan from 16–30 October 2023 with 29 observers. Observer training was continuous (N = 12), intermittent (N = 12), or untrained (N = 4). Continuously trained observers received 25 hours of visual training and completed nocturnal surveys for snakes in Guam usually >1 times per week during most weeks or otherwise regularly engaged in reptile surveys. Intermittently trained observers had received 25 hours of nocturnal visual training for brown treesnakes, with 0.1–5.1 years between their training and October 2023 (μ = 2.6 years). Untrained observers were individuals that had not received training for brown treesnake detection in Guam. We completed transects at the Seaport (N = 12), Airport West (N = 9) and Airport North (N = 19) sites each night, with roughly equal nightly survey effort by site. Each established transect was 300 m, and we placed single flagging each 10 m (10 m per min search pace) and double-reflective flagging each 50 m to assist with pacing (30 min per 300 m transect). We used a paired study design to control for observer experience and target species. On each night, a continuously trained observer was paired with an intermittently or untrained observer and transects were replicated by observer pairs in a stratified-random order. Observers completed 4–6 transects per night. Observers alternated between counting any lizards, small mammals (shrews, mice, or rats), and birds observed (ALL, N = 335) or only counting a single species of lizard by transect (LS, N = 327). The single species selected for focused species searches was a non-native skink, Lamprolepis smaragdina (emerald tree skink), that of the species available was closest in shape to a snake. However, emerald tree skinks are bright green instead of brown. Each night, we randomly assigned the first transect type (ALL or LS) to the continuously trained observer and the opposite transect type was assigned to their partner. Thereafter, order alternated between ALL and LS to control for time dependent effects on detection for each observer. Observers used two headlamp types: Lupine Wilma (continuously and some intermittently trained observers, lumens = 3200) or HP30 (Fenix, lumens = 900). We completed all work in accordance with Commonwealth of the Northern Mariana Islands Division of Fish & Wildlife permit # 24S-012N and U.S. Geological Survey Fort Collins Science Center IACUC protocol #2021-01. 20231115 Saipan Mock Response 2023 data.csv Comma Separated Value (CSV) file containing data. Producer Defined SITE The site snake Producer Defined SAXX Saipan airport Producer defined SPOR Saipan private seaport Producer defined tran_name A list of transect names, i.e., SITENAME.X_TR##, where SITENAME = SAXX or SPOR; X = N (north), W (west), or P (port); TR = transect; and ## = transect number. Producer Defined Names of the same value are the same transect. effort_date The date a survey was completed. Producer Defined 10/16/2023 10/30/2023 lamp_type The brand of a headlamp used by the observer Producer Defined Wilma Lupine, Wilma headlamp Producer defined Fenix Fenix, HP30 Producer defined observer The three digit/letter code that identified an observer - unique to an individual. Producer Defined Each different code represents a different individual. Experience The level of experience searching for brown treesnakes of each observer. Producer Defined EXP An experienced observer that received extensive training on detecting cryptic reptiles. Producer defined IEX A trained but inexperienced observer that had gone through 25 hrs of visual survey training, but did not complete these surveys at regular intervals. Producer defined NEX A completely unexperienced observer who had received no training. Producer defined Search_Days The number of days that a given observer had searched on a given survey night. Producer Defined 1 10 distance The distance searched during a given transect. Producer Defined 290 310 m start_time The time at which a survey was started, as represented by a single 24 hr period equal to 1. Producer Defined NA No Data Producer defined 0.68 0.97 ELAPSED_TIME The minutes taken to complete a survey Producer Defined 20 36 minute Rain_Now Whether it was raining during the survey. Producer Defined 0 There was no rain. Producer defined 1 It rained during the survey. Producer defined Survey_TYPE The survey type was either a survey for every lizard, mammal, and bird present or for a single lizard. Producer Defined ALL All lizards, mammals, or birds present on the transect were counted and recorded. The observer was instructed to search for all species. Producer defined LS Only a single lizard, Lamprolepis smaragdina, was searched for on the transect by an observer. All other non-brown treesnake species were ignored. Producer defined LS Counts of the lizard Lamprolepis smaragdina Producer Defined 0 30 Counts LIZARD The total number of lizards of all species counted. Producer Defined 0 69 Counts MAM The total number of small mammals (shrews, mice, and rats) of all species that were counted. Producer Defined 0 15 Counts BIRD The total number of all species of birds that were counted. Producer Defined 0 16 Counts U.S. Geological Survey - ScienceBase mailing address

Denver Federal Center

Building 810

Mail Stop 302

Denver CO 80225 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 for other purposes, nor on all computer systems, 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/P13JFSPU None 20250602 U.S. Geological Survey - PIERC USGS - NW-PACIFIC ISLAND REG Data Steward mailing and physical

Bldg 344 Crater Rim Drive

Hawaii Natl Park HI 96718 808-210-6141 pierc-datasteward@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999