Brown treesnake capture and morphometric data using live mouse- and bird-lure traps on Guam, 2013

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 plus or minus 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.