How Best To Determine How Much RatAbate Paste to Apply

Possums -

How To Determine How Much RatAbate Paste to Apply?

Diphacinone the active ingredient in RatAbate Paste has a half-life of 2.8 days which means no bio-accumulation unlike brodifacoum which has a half-life of 113 days (fisher).

The short half-life means that a rat will readily excrete diphacinone if it does not receive regular top-ups.  Rats need to feed for approximately three to five days to ensure a lethal dose.  This means you must have a reliable supply of bait.  There are several factors that influence this as outlined in points 1 to 5.

1 How much bait is placed at each baiting point

2 The number of baiting points

3 The time period between each baiting round

4 The number of mouths - a rat index RTI

5 The number of other mouths - a possum index RTC

The first thing you should check is the rat index for the block.  If rat numbers are high 50% RTI or more then you will need to check regularly that there is bait for the rats.  The second thing to do is check the possum index.  If you have over 5% RTC you might have possums eating your bait and you would need to plan to place some Feratox.  Chew cards would be good - even if you placed some around the edges you would at least get an idea of the populations you are dealing with.

Once you know what you are dealing with then you can plan your operation.

Bait placing for rats should be 50 x 50 metres and spacing can be greater following an initial control hence once into maintenance phase.  

Load up your bait stations with 200 grams which will easily fit into most Philproof or rodent bait stations. Based on this one 20kg pail will service x100 bait stations once.

You will need to place enough bait to ensure that there is an uninterrupted supply of bait for all of the rats for at least ten days or until rat activity ceases. (Ten days allows all rats to find and feed off the baits).  To get an uninterrupted supply you need to place a lot of bait initially or check regularly.  

A rough guide on working out the number of baiting points is a square 100m x 100m is 1 hectare so you would need two bait stations per hectare but might be able to cut down slightly to allow for breaks in bush/open ground etc.  You could fine tune the number and to work out how many baiting points you would need cut your block into rectangles.  Say your block is 1.2 kilometres by 1.2 km then you would need 25 x25 bait stations for a grid or 625 baiting sites.  Add 20% for rolling country and 30% for really steep country.

The key is every rat having access to bait. 

Possum Index RTC definition:  The residual trap-catch (RTC) index is a simple method of determining relative possum abundance.  The standard performance target commonly set for a reduction in possum densities, is a residual trap catch of < 5% (i.e. less than 5 possums caught for every 100 trap-nights). 

Check and follow label directions and be guided by our Best Practice RatAbate Paste.

RatAbate Paste Label:

Best Practice for Controlling Rats with RatAbate:

Chew Cards brochure:




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