Analysis of aggregated Trap.NZ data

#1

Have Trap.NZ done any analysis of the full set of data available from all project put together? I’d be interested in seeing that sort of thing if possible.

Some possibilities:

  1. A heat map of species trapped across NZ.
  2. Relative percentages that different species represent of the kills, by area, or type of area. (Urban/farmland/native bush/waterways/etc/)
  3. Time of year (e.g. month) by numbers of different species trapped, also potentially by different regions of NZ.

I’ve just done a little of this within the Owhango Alive project and one thing that really stood out was that stoat kills were very much aligned with traps that were close to major waterways.

Possibly it would be useful to allow for “lines” to be broadly categorised in terms of their location - following a waterway, urban, forestry, native bush, farmland, roadside, etc. If that additional data was provided by enough different projects then Trap.NZ could probably produce some very interesting analysis, some of which could help trappers decide the best place to put their traps.

Cheers.

#2

I have just now (14 Feb 2019) received the email from Trap.NZ with subject line " Important changes to Trap.NZ and data sharing".

The email says that data will not be aggregated at a resolution of less than 50m square. (Actually it says 50m^2 which I think should really be 50x50m (2500m^2)).

In any case I want to say I think even 50m x 50m is too fine, and that 500m by 500m (or even 1 km square) would be more appropriate if the intention is to protect privacy and locations of traps.

In our kind of project 50m x 50m data values will easily show the locations of lines, and finding the traps would be trivial.

I also have a question - what fields will be visible in aggregated data? Will any “notes” be visible, because in our data that sometimes includes names of people and properties?

#3

Thanks for that.

Yes you are right the message should have said 50x50m. We’ll see what the feedback is as others have also expressed concerns about the resolution. It may be that we 'll need to take it up a level, or possibly even have a selectable level that a project admin can choose.

Only catch totals and species counts would be collected at this stage (individual record data such as dates, notes, recorded by, images, etc, would remain private).

#4

I also have a concern that 50m x 50m is too fine and would identify a property in many cases. Going to 200m x 200m (4ha) would generalise the data better, and presumably will still enable analysis of pest movements, etc.

#5

Thanks for the feedback @PinehavenPat. We’ll look at using a larger area.