Further January Developments: Possums and revised stoat lure

 

We are starting to experiement with the visual aspect of the lure by using commercially available dog toys.   In the case of the image to the left we are starting to experiment with combining a relatively cheap dog toy with a DOC 200.   We have further modified the dog toy by inserting the 3D Printed speaker baffle into the chest of the toy.  The result has already had activity with feral cats who have interacted with the toy/lure as it is being test deployed.

We have again modified the code of our stoat version of the sound lure with coding to reflect the ability of the battery to produce sound, up to every thirty seconds.    In direct sunlight this means that the lure is running continuously during the day and is switching to a second profile activating every minute during darkness.   The lure has been placed inside a DOC200 and is being additionally baited with salted rabbit.    The speaker being used in conjunction with the set up is a four watt/eight ohms speaker.   This has been placed at deployment site one which was next to the possum activated trap, with a distressed cotton tailed rabbit sound.  During the course of a week of monitoring at this location there was minimal activations, including rats who normally would either enter or interact with the trap appearing to arrive at the site and leave immediately.  While we are conducting further testing a decision was made to move the stoat lure to another location two hundred metres away as it appeared to be that that sound of the distressed rabbit may be discouraging animals from entering the area.

We know from a year of data collection at this location that we would expect during a week considerable rodent activity and likely brush tailed possum activity, so to see neither during the week was a surprise.     We have used a DOC200 at this location with salted rabbit and caught a variety of pests using a lure making bird/chick/rat sounds and also successfully caught brush tailed possums at the site using a Timms trap modified with the lure placed at the back of the device.   We have also had incidents such as shown in the photo left where a rat has been trapped in rat box and a second rat has appeared and climbed into the possum trap (but not activated it).

In removing the stoat trap and replacing it with the rat box we have seen results more in line with what we would expect to see.   Overnight we have had two visits from brush tailed possum, possibly the same animal, an hour apart where it has approached the area, investigated the location (briefly) and then left the area within two to three minutes.    Significantly it has done so twice within an hour and the trap is activated soley on the basis of the sound without additional baiting (such as fruit).

The two pictures that are shown are an hour apart and have the brush tailed possum entering the area from a near identical direction, spending a similar time at the location (two to three minutes) then leaving the area from the same direction.

We will continue to monitor this location over the next few days to determine if a possum returns to the location and what eventuates.

Refining Stoat Traps - Airport Deployment

The start of the new year has brough a further revision of the set up deployment part of the project targetting stoats, and in particular our deployment in conjunction with the New Plymouth Airport.  We have recently spent time there upgrading the solar panels and giving the units a refresh.   They were initially deployed in June and were working consistently towards the end of September.    We have been monitoring their progress since then and have been looking for an opportunity to revise the units.

Previously we have been working off a sound activation cycle of every five minutes which has reflected the battery and in particular the solar panel units that we were charging (there will be post shortly on the specifics of what we are using and their price point essentially we were using $8.00 (NZ$) panels and have now upgraded to $25.00 (NZ$) units.    We have maintained a night cycle with the unit but the focus is very much on stoats.

The sound lure unit has been placed inside a DOC200 unit which has been baited with salted rabbit meat.    The solar panel as shown in the picture has been duct taped in place on the roof of the unit.    We have a static distressed rabbit track playing at thirty second intervals (subject to the availability of the battery strength, the computer has been coded to activate if it has the available battery strength, if not it will activate less frequently).   We are aware that there are stoats in the area based on visual sightings in the past few weeks.  

We believe that the use of a DOC200 will prevent an animal (specifically brush tailed possums) from attempting to move the unit or set it off, and we are hoping that a Stoat will access the trap in the near future.

If this is successful then we will upgrade all of our Airport units to the DOC200 as described.   We would also like to take this opportunity to thank the New Plymouth Airport for their assistance with this project.

Timms Possum Trap: Success

 

We have had a noted success using the modified version of the Timms possum trap that has been detailed on this blog.  As part of setting and preparation for the new year we have deployed again at the original deployment site.   Within three days of that we have had a capture using the modified Timms trap.   (This is the version of the trap where we have hollowed/drilled through the back of the speaker).

The unit has operated as we hoped resulting in the catpure of a large female possum on the third night of deployment.   There was significant possum activity in the night of the capture with a possum appearing to locate the trap and spend time investigating the trap before the trap was activated.   This is the second brush tailed possum that has been captured at this location within six days of deployment following the pre-Christmas capture of a brush tailed possum using a live capture trap.

We are also continuing to monitor the activations at the second deployment site which is approaching six months of monitoring.  At this location we are seeing a consistentcy on having the site with the sound lure operating of double the possums and activations compared to the non sound lure site.    

We have deployed a modified Timms possum trap at this location which has not yet produced trapping results but is clearly showing sustained possum interest in the unit.    

We are continuing to monitor these results and will be expanding the project from the end of this month when the students return to school.