Ending Deployment Site Two: Final Data

 

We have made the decision to close down the second depolyment site at this point and open additional data gathering sites.   We have completed 157 with a non sound lure location and 170 days with a sound lure location, both monitored by trail cameras.   The data from these camera has been collected using a 'fifteen minute' activation rule, that is if an activation occures within fifteen minutes it counts as part of a cluster.  We have also made the decision to count two possums as a single one for data collection purposes when it is evident that it is a mother and her baby, and to exclude domestic cats when they have been identified at a location.    The reason for the difference between days active has been the trail cameras operation or in instances when we have clearly seen possums damage the set up, in particular flipping over the solar panel, or there has been charging or battery issues with the cameras.   Due to the nature of the location and the fact it has been located on private property we have not been able to acceess it everyday to check the solar panels or cameras.    

Non sound lure location.   Set up with a Timms possum trap and rat box.   Was monitored from September 2020 to February 2021 for a total of 157 days.    During this time there were 89 animals that were seen on the camera, two of these were a local domestic cat and four of them were possum babies at a time they were been carried by their mothers.    The ratio of animals during this time was 0.52 that is a animal (which was almost exclusively possum) was detected every second day or so.  At this site we removed two rats.    There were 265 total activations (photographs) for a ratio of 1.69.

Sound Lure Location.   Set up with a Timms possum trap and rat box.    Was monitored from September 2020 to February 2021 for a duration of 170 days.   During this time there were 136 animals that were documented on camera.    The ratio of animals during this time was 0.80.    At this site we removed seven rats and a hedgehog.   Of note - six of these removals came during the first three weeks of the deployment when the sound lure was placed inside the rat box, this is something that we will be investigating further, at a variety of sites.    There were 650 activations in the form of camera shots at this location of pest animals.    This equated to a ratio of 3.8 photos per day.    

Therefore the sound lure had a ratio of animals of 0.80 compared to 0.52 at the non sound lure location.  The rate of photos at the sound lure location was 3.8 and at the non sound lure location was 1.69.

The Timms possum traps were activated at both locations a number of times but did not result in catches of animals, we are lookng at working to address this moving forward.    We are now going to move forward to having monitored locations with monitoring taking place to see if the trends shown above are replicated at other locations.  We also intend to further investigate the aspect of the sound lure working in conjunction with a rat box, with the sound coming from outside the rat box.

Although they did not wish to be identified directly we would like to express our extreme gratitude to the local farming family that allowed this monitoring on their property to occur for this length of time.

Revising Possum Sound Lures: Rat Box Retrials

At Deployment Site One we have repeated trialing variations of our Possum Sound Lure.   This location is distinct from the data gathering locations where we are maintaining consistent set ups to record the effectiveness of the lures.   One of the latest uses is bringing flashing LED lights into the equations

One of the other  questions that we have begun investigating is the sound lure acting as a deterrent at locations where it is being deployed, based on the sounds that might be playing and the volume level.    Our current set ups are involving 4w/8ohm speakers working in conjunction with the lure.   

When viewing recent footage shown by trail cameras monitoring a DOC200 trap there have been less than expected activations at the key site.    

We made a decision to return to using a rat box, which considerably muffles the sound - to see if this would have a positive effect on the number of activations as rats were particularly absent from the images.     Within the first two days of using the rat box again, after a week of using a DOC200, without general activations, there now have been two consecutive nights with a total of 64 activations, which is more in line for what we were expecting for this time of the year.    

In particular of note on the second of two nights there was repeated possum activity targetting the box.    From 9:42pm until 1:20am we saw five seperate visits to the location of the box in a series of images from brush tailed possums.   One clearly appeared to knock the box over and at least three seperate occasions possums or the possum if singular appear to try and enter the box.   This is particularly significant as the trap had peanut butter in it which had been baited the previous week had not been replaced and was not fresh, the only change with the trap was the replacing of the unit inside a rat box instead of a DOC200.      We are going to monitor this location over the next few nights to see if the same kinds of activations and details occur and will note it for further reference.

Provisional Data - End of Phase One (2020/2021)

As we start on the new phase of the sound lure project, focussed on specifically tracking the possum data from a number of locations throughout our region we have made some findings from the first stage of recording.   At the two locations that are listed below we have had two near identical set ups - a standard possum trap and a sound lure and a standard possum trap.   Both locations have been monitored by trail camers to record evidental data about what is happening at both locations.

At the longest recorded location we have been recording now for 146 days with a sound lure.  At this location 458 photographs of animals have been taken and 89 specific animals have been identified.   Taking into account the number of days there is an average of 5.5 photos a day and 0.64 animals that have appeared at this location.     

At the non sound lure location there have been a total of 199 photo graphs taken and 61 specific animals have been identified, an average of 1.61 animal photos per day and 0.54 animals have appeared at this location.

There are some factors that need to be addressed: We have had technical issues at this site address by changing the solar panel and the basic speaker deployment, which was initially inside a rat box.  This site cannot be accessed daily and during this time frame from when the units have been deployed to when they have been checked there has been clear evidence of possums expoloring the site and disturbing the set up, this has included them flipping over the solar panel or breaking the connecting wires, meaning that the unit has not been able to function as expected.

At the third location listed on this blog the non sound lure location has been monitored for twenty nine days.  During that time there have been forty two activations and eleven pest animals present.   This equates to an average activation of 0.69 per day for photographs and 0.37 for animals.   The corresponding data at the sound lure location has been monitored for forty days.   In this time there have been 719 activations (photographs) during this time an average of 17.97 per day and 123 animals for an average of 3.075 per day.

While this location has been running for less time a clearly regular patten is already being experienced at the two locations.   The heightened activity at the sound lure site at this rural location has included dramatic activity involving a possum, trapped in a head trap which then had additional possums interacting with the possum after it was deceased, this saw two hundred activations during a three day period of time.

Again at this site further recording of data and information needs to be maintained to ensure that this data is correct and reflective of the difference in the sites.

We are about to start of a significant recording process across numerous locations collecting data at each of these which we will be publishing as part of our Curious Minds Research Project.

Revised Possum Lure: Experimenting with LED/Stats Update

 

As we have detailed previously we are preparing shortly to expand the possum part of the process significantly with a fresh look at data gathering at numerous locations in our area.

At each site we are deploying sound lures focussing on possums, and having a second site in the same general location with an indentical set up without the sound lure to compare the results.   Since September 2020 we have been doing this at one location.   Currently we have data that shows at the non sound lure location we have experienced or detailed 199 images of animals and identified 61 instances of specific pest animals, by the large brush tailed possums.   At the sound lure location we have 89 instances of specific pest animals and 458 images of these animals recorded by trail cameras.   

While it is but one location the evidence is suggesting of course that there are more brush tailed possums in the location with the sound lure and the animals at the sound lure location are spending a longer time there including engaging with the sound lure.   There is evidence to show that possums are also engaging with the non sound lure location, including recently rocking or tipping over the bait station (as the mother in the picture with her joey on her back) was seen doing.   Shortly we will be conducting multiple trials with a similar set up but data will be gathered from mulitplication locations including those being conducted by outside organisations to compare to ours.

There are an additional number of aspects to the trial taking place that we will be experimenting with as well. Andrew who is responsible for desiging and creating the electronics for the project has introduced a blinking LED light.   In the example on the left the LED can be seen at the front of the unit just below the line created by the green masking tape.   The LED when the unit plays a sound will repeatedly blink.   During darkness this blink is able to be viewed or noticed from a considerable distance.   While it is currently mounted on a DOC200 the intention is to place the LED in conjunction with a possum unit to encourage possums, who appear to be very curious, to enter the unit or interact with the trap.   

At this stage the LED is red, however further research will be conducted and experimented wtih to see which colour combinations and how ofter the LED is activated to see if it increases interactions with the brush tailed possum

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.