Significant Rat Activity: Deployment Site One

We have recently begun the process of refining our deployment in preparation for the Possum part of the Curious Minds project.  As part of this process we have returned to deployment site one, which was previously used and considerable data logged.  At its height at this location at the tail end of summer there were anywhere up to a hundred activations on this site including large rats, mice and possums.

While yesterday was silent last night saw forty activations and included activity not seen before.  A large rat spent considerable time around the trap set up, including climbing over the boxes and inspecting the unit, this occurred over a duration where the lure was operating, and the lure did not scare the rat away.   The rat was subsequently trapped inside the rat box and caught.

At this point a second much larger rat, comparable to the biggest rat that has been seen at this location arrived and inspected the location.   During this time again the sound lure was repeatedly activating and had been placed on the box so it would have been loud.   The larger rat then fed on the smaller rat.  When the trap was cleared physically in the morning there was clear evidence that the first rat had been fed on.

This footage was viewed this morning, logged and then due to an extremely unfortunate technical issue the SD card with the data started displaying and error prior to it being copied across.  We are currently doing everything possible to try and retrieve this footage.

While this is only one nights activity there are some significant deductions that can be made.   

Firstly the first and second rat were not repelled by the fact that the sound lure was operating and was outside the box.   Given the duration and the time frame that both were present the lure would have been operating at full power and was outside of the box making it much louder than usual, and this was over a sustained period of time.   This did not deter either rat from the location.

Secondly it would appear that there is significant spring rat activity on this and the other side of the river which is back to levels that were noted previously at the end of Summer.    There has been a lull at this location where there was little activity previously noted.   We will continue to monitor this closely. 

Curious Minds Possum Project: Final Test Deployment

Over the past week we have had test units, with cameras and Timms possum traps placed on a local rural location.   We have been monitoring the images taken from the camera and are processing the images as part of our project.   There are two distinct sites: one with a sound lure and a Timms possum trap working in conjunction with each other and site two, which is over 100m away in another location with a Timms possums trap.   During the first week we have noticed the following:

This daytime photograph shows the site for deployment clearly shown with the trap next to the tree.   The Timms possum trap has been baited with pear.   A chew card was placed (nailed) onto the tree by this location, however it was removed as during strong winds this was creating acivations as a result of movement.

There were a number of possums that expressed interest in the trap during the week, including several who interacted with the trap, however none attempted to take the bait within the trap.

The camera has a delay of thirty seconds meaning an activation occurs if there is movement and the movement is consistent for thirty seconds.

Clearly there are a number of brush tailed possums operating in the area.  These were clearly shown numerous times on the camera, some spending time in the vicinty of the trap.

We are logging all the data (images) from the week to create a detailed level of data from the project.  A domestic cat was also seen on the images passing through the area. 

At the second location on this deployment site as shown the two traps are placed adjacent to each other.   We have the sound lure inside the rat tunnel box, this has reduced the level of sound emitting from the device significantly, however the purpose of this deployment is to test the camera and recording aspects of the project.    We also have the original sound profile that was developed which includes stoat, chick noises and two possum noises.

There were repeated interactions with rats during the week including one that was trapped in the trap.   There were interactions with rodents climbing over the trap and being seen in the area.    The rat tunnel trap was baited with peanut butter as an afterthought, it was again, an opportunity to check camera deployment and ensure that issues would not be present such a 'false' images created by high winds.

There was one significant interaction with a brush tailed possum, shown on the image on the left.   The possum did not stay in the area of the trap.   

In summary the week long deployment has provided significant images of high quality to ensure that we can monitor effectively what is happening at local sites where the lures are deployed.   Having a thirty second camera delay ensures that high winds do not produce a significant amount of false activations, where no animals are present.    We will now deploy at this site for a significant length of time monitoring what is occurring at the sites where the sound lures and non sound lure sites.    This will allow us to see and show clear evidence of what is happening and show proof of the effectiveness of the lures.   These will be set up to specificallly target possums, at present we are using a generic sound profile with a mix of animals.     Shortly we will move to a possum specific lure that will remain silent during the day and play possum specific calls and noises at night.   We will also look at placing the lure outside of the rat box as this will significantly increase the volume that will be produced (and thereby increase the sound profile of the lure).    

Significant Large Rat Activity

The continued use of the rodent targetted sound profile is showing considerable change in results.  We have started to see a shift from mice towards having possums and larger rodents appear.    There has been two instances of large rats appearing and spending considerable time interacting with the lure within a week.   In post cases the rat is spending time with the lure.   Based on the size of rat, it would appear that it would be larger than the trap and as a result it would be limited in its ability to remove the rat.   A much better option for a rat this size would be a DOC 200 - we currently do not have this option deployed with the sound lure as it is being tested in another location.   We are also going to use telemetry to measure the effectiveness of the battery relative to the sound profile.

In general terms the rat investigates the traps, appears to have shown interest in both traps and may have caused an activation in the t-rex trap, although it did not trap the rat.   It has also climbed over both boxes and spent nearly ten minutes in the vicinity of the trap.   This is the second time in seven calendar days that a large rat has interacted with the trap, this has now been deployed for five weeks and the rat interactions have both occurred in the last week since the change of the sound profile.   With the lure track playing every minute the lure has played repeatedly while the rat is in the vicinity of the trap.

We are continuing to research the target animals (Possums) and looking at while there may be possible variations with the sound lure.   There is some evidence to suggest that cats and cat smells can act as a deterent to Possums - this is a considerable issue at this deployment site.   The domestic cats are familiar with the site and one of the two cats is waiting at the site unitl the lure is deployed each night - and there is also evidence to show the cat is present repeatedly during the night.   This would potentially indicate that this is deterring the visit of target animals to the site.

This photograph is from the developing Instagram account for this project.   This is the cat that is mentioned and featured on this blog, waiting for the lure to go in place close to the tree.