Cocos Island brown treesnake invasion baiting and trapping pilot study data

Metadata:
Identification_Information:
Citation:
Citation_Information:
Originator: Siers, Shane R.
Publication_Date: 2023
Title:
Cocos Island brown treesnake invasion baiting and trapping pilot study data
Geospatial_Data_Presentation_Form: tabular digital data
Series_Information:
Series_Name: Research Dataset Series
Publication_Information:
Publication_Place: Fort Collins, CO
Publisher: USDA, APHIS, WS National Wildlife Research Center
Online_Linkage: https://doi.org/10.2737/NWRC-RDS-2023-003
Description:
Abstract:
In October of 2020, a new population of invasive brown treesnakes (Boiga irregularis) was discovered on the 33-ha island of Cocos Island, Guam. Trapping and bait fate pilot studies (NWRC QA-3106 and QA-3340) were conducted to evaluate potential eradication tools for this species. These studies sought to evaluate the usefulness of toxic baiting with acetaminophen-treated carrion baits and cage trapping, which are common tools for the control of brown treesnakes on mainland Guam. From December 2020 through April 2021 multiple bait types and bait presentations were used on 9 transects along existing paths and trails, including on the ground, suspended in the canopy emulating aerial bait applications, and in four plastic-tube bait station configurations intended to exclude nontarget species. All baits were monitored weekly with time lapse cameras and the following data recorded for the baiting study: location, type of presentation, bait and dosage of acetaminophen (0 or 80 milligrams), date and time of first bait monitoring image as well as the date and time of the take or ending period, and the species that took the bait. For the pilot trap study we tested two trap types (99 of each) commonly used on Guam and compared trapping success with live versus dead mouse lures. Traps were checked approximately every 2 weeks between June and August 2021 and the following data recorded: trap location, type and condition of lure, nontarget captures found in the traps, trap damage caused by nontarget species, and snake captures (which was only one in this study).
Purpose:
Evaluate the utility of trapping and baiting for eradication of a newly-discovered population of invasive brown treesnakes on Cocos Island, Guam.
Supplemental_Information:
For more information about this study and these data, see Siers et al. (2024).

These data were originally published on 10/05/2023. On 03/01/2024, the metadata was updated to include more details for the recently published article.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20201216
Ending_Date: 20200809
Currentness_Reference:
Ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Description_of_Geographic_Extent:
This study took place in Cocos Island (33.6 hectares), which is centered at approximately 13.238° latitude and 144.653° longitude and located 2.5 kilometers southwest from the southern coast of Guam, forming part of the Merizo Barrier Reef surrounding Cocos Lagoon.
Bounding_Coordinates:
West_Bounding_Coordinate: 144.644
East_Bounding_Coordinate: 144.659
North_Bounding_Coordinate: 13.243
South_Bounding_Coordinate: 13.235
Bounding_Altitudes:
Altitude_Minimum: 1
Altitude_Maximum: 15
Altitude_Distance_Units: meters
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: biota
Theme:
Theme_Keyword_Thesaurus: National Research & Development Taxonomy
Theme_Keyword: Wildlife (or Fauna)
Theme_Keyword: Forest & Plant Health
Theme_Keyword: Invasive species
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: trapping
Theme_Keyword: baiting
Theme_Keyword: brown treesnake
Theme_Keyword: brown tree snake
Theme_Keyword: Boiga irregularis
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Guam
Place_Keyword: Cocos Island
Taxonomy:
Keywords/Taxon:
Taxonomic_Keyword_Thesaurus:
None
Taxonomic_Keywords: single species
Taxonomic_Keywords: animals
Taxonomic_System:
Classification_System/Authority:
Classification_System_Citation:
Citation_Information:
Originator: ITIS
Publication_Date: 2023
Title:
Integrated Taxonomic Information System (ITIS)
Geospatial_Data_Presentation_Form: online-database
Other_Citation_Details:
Retrieved [April 24, 2023]; CC0
Online_Linkage: https://www.itis.gov
Online_Linkage: https://doi.org/10.5066/F7KH0KBK
Taxonomic_Procedures:
Taxonomic_Classification:
Taxon_Rank_Name: Kingdom
Taxon_Rank_Value: Animalia
Applicable_Common_Name: Animal
Applicable_Common_Name: animaux
Applicable_Common_Name: animals
Taxonomic_Classification:
Taxon_Rank_Name: Subkingdom
Taxon_Rank_Value: Bilateria
Taxonomic_Classification:
Taxon_Rank_Name: Infrakingdom
Taxon_Rank_Value: Deuterostomia
Taxonomic_Classification:
Taxon_Rank_Name: Phylum
Taxon_Rank_Value: Chordata
Applicable_Common_Name: cordés
Applicable_Common_Name: cordado
Applicable_Common_Name: chordates
Taxonomic_Classification:
Taxon_Rank_Name: Subphylum
Taxon_Rank_Value: Vertebrata
Applicable_Common_Name: vertebrado
Applicable_Common_Name: vertébrés
Applicable_Common_Name: vertebrates
Taxonomic_Classification:
Taxon_Rank_Name: Infraphylum
Taxon_Rank_Value: Gnathostomata
Taxonomic_Classification:
Taxon_Rank_Name: Superclass
Taxon_Rank_Value: Tetrapoda
Taxonomic_Classification:
Taxon_Rank_Name: Class
Taxon_Rank_Value: Reptilia
Applicable_Common_Name: répteis
Applicable_Common_Name: reptiles
Applicable_Common_Name: Reptiles
Taxonomic_Classification:
Taxon_Rank_Name: Order
Taxon_Rank_Value: Squamata
Applicable_Common_Name: Amphisbaenians
Applicable_Common_Name: Lizards
Applicable_Common_Name: Snakes
Applicable_Common_Name: amphisbènes
Applicable_Common_Name: lézards
Applicable_Common_Name: serpents
Taxonomic_Classification:
Taxon_Rank_Name: Suborder
Taxon_Rank_Value: Serpentes
Applicable_Common_Name: Snakes
Applicable_Common_Name: cobra
Applicable_Common_Name: serpente
Applicable_Common_Name: serpents
Taxonomic_Classification:
Taxon_Rank_Name: Infraorder
Taxon_Rank_Value: Alethinophidia
Taxonomic_Classification:
Taxon_Rank_Name: Family
Taxon_Rank_Value: Colubridae
Applicable_Common_Name: Colubrids
Applicable_Common_Name: Typical Snakes
Taxonomic_Classification:
Taxon_Rank_Name: Subfamily
Taxon_Rank_Value: Colubrinae
Taxonomic_Classification:
Taxon_Rank_Name: Genus
Taxon_Rank_Value: Boiga
Applicable_Common_Name: Boigas
Applicable_Common_Name: Catsnakes
Taxonomic_Classification:
Taxon_Rank_Name: Species
Taxon_Rank_Value: Boiga irregularis
Applicable_Common_Name: Brown Tree Snake
Applicable_Common_Name: Brown Treesnake
Applicable_Common_Name: Brown Cat Snake
Access_Constraints: None
Use_Constraints:
These data were collected using funding from the U.S. Government and can be used without additional permissions or fees. If you use these data in a publication, presentation, or other research product please use the following citation:

Siers, Shane R. 2023. Cocos Island brown treesnake invasion baiting and trapping pilot study data. Research Dataset Series. USDA, APHIS, WS National Wildlife Research Center. Ft. Collins, Colorado. https://doi.org/10.2737/NWRC-RDS-2023-003
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA, APHIS, Wildlife Service, National Wildlife Research Center
Contact_Person: Shane R. Siers
Contact_Position: Supervisory Research Wildlife Biologist
Contact_Address:
Address_Type: mailing and physical
Address: 233 Pangelinan Way
City: Barrigada
State_or_Province: Guam
Postal_Code: 96913
Country: USA
Contact_Voice_Telephone: 671-686-1334
Contact_Electronic_Mail_Address: shane.r.siers@usda.gov
Contact Instructions: This contact information was current as of original publication date. For current information see Contact Us page on: https://doi.org/10.2737/RDS.
Data_Set_Credit:
This project was funded by the U.S. Department of Interior, Office of Insular Affairs as well as the U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services National Wildlife Research Center.


Author Information:

Shane R. Siers
USDA, APHIS, Wildlife Service, National Wildlife Research Center
https://orcid.org/0000-0001-7961-5072
Cross_Reference:
Citation_Information:
Originator: Siers, Shane R.
Originator: Nafus, Melia G.
Originator: Calaor, Jeried E.
Originator: Volsteadt, Rachel M.
Originator: Grassi, Matthew G.
Originator: Volsteadt, Megan
Originator: Collins, Aaron F.
Originator: Barnhart, Patrick D.
Originator: Huse, Logan T.
Originator: Yackel Adams, Amy A.
Originator: Vice, Diane L.
Publication_Date: 2024
Title:
Limitations of invasive snake control tools in the context of a new invasion on an island with abundant prey
Geospatial_Data_Presentation_Form: journal article
Series_Information:
Series_Name: NeoBiota
Issue_Identification: 90: 1-33
Online_Linkage: https://doi.org/10.3897/neobiota.90.103041
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
All true and accurate. Data are independently proofed by personnel other than those that entered data. Siers, the Principal Investigator, also review data before analysis to ensure consistency of coding, look for unexpected or unreasonable values, etc. Where corrections are made, notes include the original uncorrected value.
Logical_Consistency_Report:
The data are logically consistent. The consistency was verified as part of the quality assurance that occurred during data analysis.
Completeness_Report:
No data were intentionally omitted. However, there is one case where a camera was not set so we are missing data for this observation and data are denoted as "NA". Additionally, sometimes dates when data were entered or proofed were not available for the bait data and were recorded as blank values.
Lineage:
Methodology:
Methodology_Type: Field
Methodolgy_Identifier:
Methodolgy_Keyword_Thesaurus:
None
Methodology_Keyword: trapping
Methodology_Keyword: bait fate
Methodology_Description:
STUDY LOCATION

The substrate in Cocos Island, Guam is deep, well-drained loamy sand. The vegetation is primarily Casuarina equisetifolia forest in the northeast, while the southwestern portion of the island is primarily mixed strand forest comprising Cocos nucifera, Hernandia sonora, Guettarda speciosa, Merrilliodenron megacarpum, Morinda citrifolia, Intsia bijuga, Casuarina equisetifolia, Terminalia catappa, Tournefortia argentea, Carica papaya, Barringtonia asiatica, Hibiscus tiliaceus, Leucaena leucocephala and Thespesia populnea. Vegetation along the southeastern shore is dominated by Pemphis acidula and Scaevola sericea, while the northwestern coastline is mostly open sand.

The northeastern 80% of the island is under private ownership and the southwestern 20% is owned by the Government of Guam and managed by the Guam Department of Parks and Recreation. The island is uninhabited, but Cocos Island Resort operates as a day resort offering watersports, trail walks, and food and beverages. The resort was closed at the time of this study due to the COVID-19 pandemic.

To minimize disturbance of threatened and endangered species present on the island, our activities were limited to the edges of existing roads and footpaths.


ACETAMINOPHEN BAITING

We sought to evaluate the relative merits of a variety of potential baits and bait presentation methods on Cocos Island. Preliminary evidence from mainland Guam indicates that brown treesnakes with recent experience feeding on birds may be preferentially attracted to dead bird baits over dead rodents. To evaluate bait preferences, we offered 3 sizes of dead mice and 2 sizes of dead bird chicks as baits, where suitable to the presentation method: 4–6-gram (g) dead neonatal mice (DNM); 10–17-g small mice (SM); 18–35-g large mice (LM); 10–14-g small bird baits (hatchling quail, SB); and 25–35-g large bird baits (hatchling chickens, LB). All baits were monitored with commercial infrared game cameras (H68, Apeman, Shenzhen, China) set to time lapse with one image recorded every 30 seconds for 24 hours per day.

Canopy presentation: USDA Wildlife Services (WS) has engineered an Aerial Delivery System (ADS) for the automated assembly and aerial distribution of bait cartridges containing a DNM treated with a tablet containing 80 milligrams (mg) of acetaminophen. These cartridges open upon ejection from the aircraft, exposing a ribbon to cause entanglement in the forest canopy where arboreal treesnakes forage, preventing baits from falling to the forest floor where they can be taken by terrestrial nontarget species such as crabs. We emulated aerial bait applications by positioning opened ADS cartridges on a simulated branch (45-centimeter [cm] wooden dowel) with the DNM hanging in the field of view (FOV) of a camera mounted atop a painter’s pole, extended into the forest canopy, and temporarily lashed to natural vegetation with bungee cords.

Ground presentation: Because some ADS baits fail to tangle in the canopy, or DNM may become unstuck from the cartridge and fall through to the forest floor, we sought to evaluate the fate of DNM on the ground. Also, recent evidence suggests that ADS treatments might not adequately expose large brown treesnakes to baits; larger brown treesnakes are more prone to foraging on the ground, might be preferentially attracted to larger baits, and might require greater doses of acetaminophen for effective removal. Moreover, the estimated take rates for large ground baits in a treated population on Guam is greater than for standard ADS baits. For these reasons, WS has considered an alternative aerially-delivered bait system comprising a slightly larger mouse (SM) placed in the same bait cartridge tube but without the ribbon assembly, which would let the bait fall to the forest floor where larger snakes may be more effectively targeted. We also considered that even larger baits placed on the forest floor, potentially containing larger doses of acetaminophen, could more effectively target larger ground-foraging snakes, so we incorporated LM and LB into ground presentations. Ground baits were placed on a small, thin PVC plastic platform printed with 20-cm size standards and lashed to a 0.9-kilogram (kg) lead diving weight to prevent small crabs from dragging the bait out of the FOV of the cameras. Cameras were mounted directly overhead on tripods fashioned from inexpensive extruded metal tubing. Brown treesnake head measurements taken from overhead images containing a size standard can be used to estimate snake size.

Because both canopy and ground baits are not protected from being taken by nontarget species, we did not treat these baits with acetaminophen tablets for this pilot evaluation.

Bait station presentations: Polyvinyl chloride (PVC) tube bait stations (‘bait tubes’) are intended to exclude nontarget species that might interfere with baits, making them unavailable to brown treesnake, and to protect native species from unintentional exposure to acetaminophen intoxication. Standard operational baiting methods include placing a DNM treated with a tablet containing 80 mg of acetaminophen into a 5-cm diameter, 30-cm long PVC bait tube, with 6.35-millimeter (mm) bolts crossing the openings at the ends to further prevent ingress by nontargets. Bait tubes are usually suspended horizontally by two lengths of paracord from existing vegetation or structures such as fence lines. Based on the average size of brown treesnakes recovered from Cocos Island prior to the testing of these tools, we elected to deploy larger baits (SM, LM, SB, and LB) within our bait stations on Cocos Island. We evaluated standard 5 × 30-cm horizontal bait tubes as well as alternative designs intended to more reliably exclude nontarget species such as crabs and monitor lizards: longer 5 × 45-cm horizontal bait tubes; vertical 5-cm diameter × 30-cm long bait tubes capped at the top end; and capped vertical 10-cm diameter × 30-cm long bait tubes. Both horizontal bait tube designs included bolts across the openings, while vertical tubes did not as the bolts could be used by nontargets to assist climbing into the tubes.

We suspended all bait station types by paracord from a wooden dowel armature to which the trail camera was affixed, locking the bait in the FOV of the camera. We temporarily attached these armatures to existing vegetation by elastic cords, with minor vegetation pruning to ensure that leaves or branches did not obstruct the view of the bait. We placed baits in the center of horizontal tubes where they were held in place by gravity and friction alone. Within vertical bait tubes, we attached baits within the caps clipping one foot with a small metal spring clamp, holding baits in place but making them easily removed with a slight tug from snakes or nontargets. Because cameras could not directly view baits in the vertical tubes, we tied a length of white biodegradable flagging tape to one leg of each bait and pulled the tape through a small hole in the side of the tube; when the bait was removed, the flag disappeared and the animal within the FOV of the camera at that time was attributed with the bait removal.

Because bait stations offered some degree of protection from nontarget interference, we treated baits in bait stations with tablets containing 80 mg of acetaminophen inserted into the body of the bait via the oral cavity, to remove any brown treesnakes that took baits.

We spaced bait placements at approximately 20-meter (m) intervals along existing paths and trails on Cocos Island; off-path trekking was not authorized by the U.S. Fish and Wildlife Service prior to a formal endangered species consultation process. Paths were subdivided into 9 segments (transects). Each week between December 2020 and April 2021 (18 weeks) we placed 36 bait monitoring stations along one transect, alternating each of 3 presentation types (12 stations each). We monitored each transect of 36 stations for one week, with the bait checked and replaced once mid-week with a fresh bait, for baiting intervals of 3 to 4 days. During weeks 1–9, we placed canopy, ground, and standard 5 × 30-cm horizontal tubes in alternating positions along the transect, with bait types alternated as appropriate to the objectives of the presentation type. During weeks 10–18, we alternated 5 × 45-cm horizontal tubes and the two vertically oriented tube types (5 × 30 and 10 ×30 cm), along with alternating bait types. At bait checks, if a bait appeared to have been taken we reviewed camera images to identify the time of bait removal and the species taking the bait.


LIVE TRAPPING

After years of experimentation with multiple live trap designs, a modified crayfish or minnow trap was adopted as the standard brown treesnake live trap used on Guam. The original trap is a two-piece dual-funnel design of galvanized wire mesh with the entrances modified with a PVC ring holding a one-way wire mesh flap that allows access to the trap body but blocks escape by snakes. Snakes are lured into the traps by a live mouse in a protected wire mesh chamber held within the trap body. This two-piece design was later adapted for operational purposes by creating a single-piece body of more durable stainless steel, accessed by removing one of the funnel ends, and incorporating the mouse chamber into the trap body so that the mouse can be serviced without opening the trap. In both trap types, mice are provisioned with a custom-made block of commercial seed and pellet mix embedded in a paraffin wax matrix which prevents exposure to the elements until the mouse chews through the wax. A piece of fresh potato provides the necessary water. The use of live mouse lures is less than desirable due to maintenance expense and perceptions regarding animal welfare; however, despite extensive efforts, no trap lure has been found to be nearly as effective and practical as a live mouse. Prior to verification of brown treesnake presence on the island, Guam’s Division of Aquatic and Wildlife Resources (GDAWR) and the USGS RRT performed surveillance trapping using dead mouse and rat lures due to concerns about escaped live mice establishing a population on the island (D. Vice, GDAWR, personal communication) but no snakes were ever captured in these traps. Prior to this study, there were no reported head-to-head tests of live versus dead mouse lures in brown treesnake traps.

To evaluate differences in efficacy and durability between trap types, and capture success between live and dead mouse lures, we alternated 99 one-piece WS Standard and 99 original two-piece traps approximately every 20 m along the same existing trails as the previous baiting trials. We alternated live and dead mouse lures between every pair of 2 trap types (repeating the order of 1-piece/live, 2-piece/live, 1-piece/dead, 2-piece/dead, etc.) for a total of 100 traps with live mouse lures and 98 with dead mice. Following the typical use patterns of these two trap types, we hung 1-piece traps on nylon paracord and 2-piece traps on metal tie wire, at about waist to chest height on existing vegetation. Between June and August 2021 we checked traps twice weekly (every 3 or 4 days) for 55 nights, reprovisioning live mouse lures and replacing dead mouse lures with fresh dead mice. We recorded brown treesnake captures, nontarget captures, and trap damage caused by nontarget species. We also recorded traps as nonfunctional when missing lures, with funnel flaps stuck open or closed, with large holes due to crab damage, or with other defects making them unlikely to capture or prevent escape by snakes. Because traps were confirmed to be functional at the beginning of each trap-checking interval, we assumed traps became nonfunctional approximately mid-interval, on average, so reduced our tally of effective trap nights by one-half of the checking interval per nonfunctioning trap.

We monitored a subset of 20 traps via infrared game cameras (Hyperfire 2, Reconyx, Holmen, Wisconsin). We arrayed 10 cameras evenly along a rock retaining wall and another 10 along a transect through a bird roosting area. We positioned half of these cameras on traps with live mouse lures, and the other half on traps with dead mice. We recorded time-lapse images (1 photo every 60 seconds) between 1800 and 0600 to observe for brown treesnakes investigating traps but failing to enter, as has been commonly documented on mainland Guam. Throughout the evaluation of control tools, USGS conducted nocturnal visual searches and hand-removal of brown treesnakes. (USGS data for hand-captures are not included in this data package.) Methods followed those applied on Guam in which individuals surveyed transects after dusk using powerful headlamps (Wilma, Lupine Lighting System, Lebanon, PA, USA) walking a slow searcher pace such that each transect (approximately 400 m) lasted approximately 1 hour.


For more details see Siers et al. (2024).
Methodology_Citation:
Citation_Information:
Originator: Siers, Shane R.
Originator: Nafus, Melia G.
Originator: Calaor, Jeried E.
Originator: Volsteadt, Rachel M.
Originator: Grassi, Matthew G.
Originator: Volsteadt, Megan
Originator: Collins, Aaron F.
Originator: Barnhart, Patrick D.
Originator: Huse, Logan T.
Originator: Yackel Adams, Amy A.
Originator: Vice, Diane L.
Publication_Date: 2024
Title:
Limitations of invasive snake control tools in the context of a new invasion on an island with abundant prey
Geospatial_Data_Presentation_Form: journal article
Series_Information:
Series_Name: NeoBiota
Issue_Identification: 90: 1-33
Online_Linkage: https://doi.org/10.3897/neobiota.90.103041
Process_Step:
Process_Description:
Original data were hand-written on paper at time of field work and then later entered into Microsoft Excel by the observer and proofed by another observer. Collated and curated by a data manager.
Process_Date: Unknown
Process_Step:
Process_Description:
Data were converted to comma-separated values files by the FS Research Data Archive team as part of the archival process.
Process_Date: 2023
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Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:
Below you will find a list and description of the files included in this data publication.

VARIABLE DESCRIPTION FILES (1)

1. \Data\_variable_descriptions.csv: Comma-separated values (CSV) file containing a list and description of variables found in all data files. (A description of these variables is also provided in the metadata below.)

Columns include:

Filename = name of data file
Variable = name of variable
Units = units (if applicable)
Precision = precision (if applicable)
Description = description of variable


INFORMATION FILES (1)

1. \Data\species_codes.csv: CSV file containing a list and description of the nontarget species codes used in QA-3106_Cocos_Bait_Fate_Data.csv.

Columns include:

spec = codes used to define species ('spec') found in QA-3106_Cocos_Bait_Fate_Data.csv
description = description of spec


DATA FILES (4)

1. \Data\QA-3106_Cocos_Bait_Fate_Data.csv: CSV file containing weekly data collected during the December 2020 through April 2021 pilot study to determine target (brown treesnake) and nontarget uptake of various baits in various bait stations that could be used for invasive snake control on Cocos Island (only baits in nontarget-excluding bait stations were acetaminophen-treated).

Variables include:

site = site code (e.g., 'Cocos')

trans = transect number

no = number of trial/device (1-36)

pres = bait presentation type (pre-filled in template where 18 = 18 inch horizontal tube bait station, canopy = DNM elevated on painter’s pole into canopy, ground = bait presented on the ground, tube = standard 12 inch horizontal bait tube, V2 = vertical bait tube with 2 inch diameter, V4 = vertical bait tube with 4 inch diameter)

latitude = latitude (WGS84 datum, decimal degrees)

longitude = longitude (WGS84 datum, decimal degrees)

cam = camera number

sd = SD card number

round = each location was baited twice; baiting round 1 or baiting round 2

setdate = date transect was set (dd-Mon-yy)

checkdate = date transect was checked (dd-Mon-yy)

by = initials of person(s) doing the check

bait = type of bait (AGB = 13-17-g mouse (alternative ground bait), DNM = 4–6-gram (g) dead neonatal mice, LB = 25–35-g large bird baits (hatchling chickens), LM = 18–35-g large mice, SB = 10–14-g small bird baits (hatchling quail), SM = 10–17-g small mice)

dose = dose of acetaminophen in bait (0, 80 mg)

status = status at checkdate (Fell = bait fell from the simulated bait cartridge due to putrefaction or consumption by insects, NF = Not Functional, NT = Not Taken, PT = Partially Taken (other than insects/maggots), SK = Skeleton/Skin, T = Taken (gone))

note = notes taken at checkdate (where BA = blank ants, RA = red ants, DNM = dead neonatal mouse)

start = time and date of first bait monitoring image (mm/dd/yyyy hh:mm:ss in 24 hours) (blanks are start or end dates and times that are not available because of camera malfunction, inability to precisely determine the end time of a trial when baits were slowly removed by ants, or bait takes that could not be seen on camera)

end = time and date bait monitoring ended (mm/dd/yyyy hh:mm:ss in 24 hours), either the time of the take or the end of the monitoring period [FOR GROUND BAITS, THIS WILL BE THE FIRST ENCOUNTER WITH A SPECIES LARGE ENOUGH TO TAKE THE BAIT E.G. CC, MON, BTS] (blanks are start or end dates and times that are not available because of camera malfunction, inability to precisely determine the end time of a trial when baits were slowly removed by ants, or bait takes that could not be seen on camera)

spec = code for species that took the bait, see species_codes.csv for a description of each code (NOTE: if any rat, mouse, or shrew was observed it was reported to the PI immediately)

other = code for other species encountering but not taking the bait, or encountering a ground bait after it was already considered "taken" by another species, see species_codes.csv for a description of each code

encnotes = any noteworthy observations about encounters with the bait or bait condition

QC = data quality control notes

enterby = initials of the person who entered the data into a spreadsheet

enterdate = date data were entered (dd-Mon-yy)

proofby = initials of the person who checked (proofed) the data

proofdate = date data were proofed (dd-Mon-yy)



2. \Data\QA-3340_Cocos_Trap_Locations.csv: CSV file containing detailed information about the traps used in trap pilot study.

Variables include:

trapnum = trap number (1-198)

mouselure = type of mouse lure used in trap (live = live mouse, dead = dead mouse)

traptype = type of trap at location (one-piece stainless steel = one-piece stainless steel WS standard trap, two-piece galvanized = two-piece galvanized modified crayfish trap)

latitude = trap location latitude (WGS84 datum, decimal degrees)

longitude = trap location longitude (WGS84 datum, decimal degrees)



3. \Data\QA-3340_Cocos_Trap_Observations.csv: CSV file containing the biweekly data collected during the July through August 2021 pilot study to determine the effectiveness of different traps and mouse lures.

Variables include:

checkdate = date trap was checked (dd-MON-yy)

setdate = date trap was set (dd-MON-yy)

elapsed = number of days between trap checks

trapnum = trap number (1-198)

nf = trap non-functional (Yes or No)? NF means no bait or lure; funnel door stuck in open position; large hole in mesh from which a snake could escape; trap missing (stolen or in shop)

traptype = trap type (1-piece = 1-piece stainless, 2-piece = 2-piece galvanized)

luretype = lure type (Dead, Live)

lurecondition = condition of lure (OK = lure good, mouse alive or dead mouse present; Dead = live mouse was found dead; Missing = live or dead mouse lure was taken or escaped)

nontarget = non-target animal caught in the trap (AC = Anolis carolinensis, CC = coconut crab, EC = Emoia caeruleocauda, GE = unidentifiable gecko species, GO = Gehyra oceanica, HC = hermit crab, VI= Varanus indicus (monitor), Other = other species)

species = additional non-target animals caught in trap (AC = Anolis carolinensis, BTS = Brown treesnake, CC = coconut crab, EC = Emoia caeruleocauda, GO = Gehyra oceanica, HC = hermit crab, VI = Varanus indicus (monitor), UNK = unknown)

bag = bag number of VI (monitor lizard) captured and brought back to Wildlife Services office for delivery to Guam Division of Aquatic and Wildlife Resources

dmg = was the trap damaged? (Y = yes, N = no)

repairmin = how many minutes did it take to repair the trap?

inshop = did the trap have to be removed for repair in the shop? (Y = yes)

notes = notes recorded at time of data collection (where AC= Anolis carolinensis, CC = coconut crab, EC= Emoia caeruleocauda, GO = Gehyra oceanica, HC/HCR = hermit crab, RA = Red ant, VI= Varanus indicus)

Entered = initials of the person who entered the data

Proofed = initials of the person who checked (proofed) the data



4. \Data\QA-3340_Cocos_Trap_SnakeCaptures.csv: CSV file containing information about any brown treesnakes captured in the pilot trap study. (In this study only one snake was captured.)

Variables include:

checkdate = date trap was checked (dd-MON-yy)

trapnum = trap number (1-198)

bag = bag number into which the snake was placed; only one snake per bag; can have multiple snakes in one bag from ONE trap

id = ID number (100-199); USGS assigned grouping of brown treesnakes (BTS) ID#s CC100-199

svl = snout-vent length (millimeters [mm])

tl = total length (mm)

mass = snake weight (grams [g])

sex = sex of snake (M = male, F = female) based on probing only

bulge = Was a prey bulge present? (0 = none; 1 = not visible, but palpable; 2 = visible bulge)

fol = number of enlarge follicles palpable, if a female snake (if gravid with eggs, record in notes)

obs = initials of the person (observer) performing the measurements

notes = notes about the condition of the snake or the circumstances of the capture
Entity_and_Attribute_Detail_Citation:
Siers, Shane R.; Nafus, Melia G.; Calaor, Jeried E.; Volsteadt, Rachel M.; Grassi, Matthew G.; Volsteadt, Megan; Collins, Aaron F.; Barnhart, Patrick D.; Huse, Logan T.; Yackel Adams, Amy A.; Vice, Diane L. 2024. Limitations of invasive snake control tools in the context of a new invasion on an island with abundant prey. NeoBiota. 90: 1-33. https://doi.org/10.3897/neobiota.90.103041
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA Forest Service, Research and Development
Contact_Position: Research Data Archivist
Contact_Address:
Address_Type: mailing and physical
Address: 240 West Prospect Road
City: Fort Collins
State_or_Province: CO
Postal_Code: 80526
Country: USA
Contact_Voice_Telephone: see Contact Instructions
Contact Instructions: This contact information was current as of March 2024. For current information see Contact Us page on: https://doi.org/10.2737/RDS.
Resource_Description: NWRC-RDS-2023-003
Distribution_Liability:
Metadata documents have been reviewed for accuracy and completeness. Unless otherwise stated, all data and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. However, neither the author, the Archive, nor any part of the federal government can assure the reliability or suitability of these data for a particular purpose. The act of distribution shall not constitute any such warranty, and no responsibility is assumed for a user's application of these data or related materials.

The metadata, data, or related materials may be updated without notification. If a user believes errors are present in the metadata, data or related materials, please use the information in (1) Identification Information: Point of Contact, (2) Metadata Reference: Metadata Contact, or (3) Distribution Information: Distributor to notify the author or the Archive of the issues.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: CSV
Format_Version_Number: see Format Specification
Format_Specification:
Comma-separated values file (CSV)
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: https://doi.org/10.2737/NWRC-RDS-2023-003
Fees: None
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Metadata_Reference_Information:
Metadata_Date: 20240301
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA, APHIS, Wildlife Service, National Wildlife Research Center
Contact_Person: Shane R. Siers
Contact_Position: Supervisory Research Wildlife Biologist
Contact_Address:
Address_Type: mailing and physical
Address: 233 Pangelinan Way
City: Barrigada
State_or_Province: Guam
Postal_Code: 96913
Country: USA
Contact_Voice_Telephone: 671-686-1334
Contact_Electronic_Mail_Address: shane.r.siers@usda.gov
Contact Instructions: This contact information was current as of original publication date. For current information see Contact Us page on: https://doi.org/10.2737/RDS.
Metadata_Standard_Name: FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001.1-1999
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