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A Cautionary Tale of Tahr

A simple mistake crept into a map just recently so this post is a cautionary tale about being very thorough about checking all aspects of your map before it is “done”.

This post is written as a cautionary tale.  Here’s the background.  I recently got an email from Geoff Kerr, who serves on the board of the Game Animal Council.  You may have been hearing about Department of Conservation’s plan to cull Himalayan Tahr in the South Island.  As you might have seen, this has been a contentious issue and I won’t cover the politics of this.  Geoff was heading north for meetings with hunters and the minister and was asking for some maps at somewhat short notice.  So with a bit of data, I got started.  He sent me a shapefile of zones across the Southern Alps set up for tahr management:

Next, he was interested in showing where the conservation land was within those zones, so I clipped out the areas within the management zones and added them to the map:

Then I figured out that it would be better to show those areas that are NOT public land.  Easy enough – I used the Erase tool to remove the DOC areas from the management units (this worked as the management units were polygons):

So after several emails back and fourth and four different versions, this was the map that we settled on (at an A4 size):

Geoff also asked for some large format versions, so I saved two versions of the same map, one at A1 size and one at A0.  This was an easy thing to do.  Rather than creating a new map and having to add and symbolise the data to match, I saved the A4 version to a new map document and went to File > Page and Print Setup…, setting the Map Page Size to, in this case, A0:

Notice the preview at bottom right – this shows the A4 size map and how it would appear on the A0 page – not very inspiring.  By ticking the “Scale Map Elements proportionally to changes in Page Size”, problem solved:

I did end up resizing the unit numbers so that were a bit easier to read but that was about it.  Did the same for the A1 size and sent copies to Geoff for printing.  A key point here is that the two new maps were based on the original map document.

Maps under arm, Geoff headed north for meetings, including with the minister and he seemed happy with the maps.  Another job done, I thought.  That was until I got another email from Geoff pointing out an error (well, two actually, but we’ll just cover one here).  Let’s go back to the original A4 map:

Notice any problems there?  I certainly didn’t.  It’s a pure rookie error:

It’s “Himalayan” not “Himilayan”…  Ugh – I absolutely hate making errors like this.  Sure it’s a minor typo, but what it serves to do is to undermine the confidence my reader can have in the map.  There’s no better way to reduce the impact of your map (and let’s not limit it to just a map – the same holds true for any written document).  To imagine all those people looking at this map left me with a clenched jaw and a semi-sleepless night.  For future maps I’ve already corrected this but there’s nothing I can do to change the first impressions this map created.  This was an easy one to fix and I missed it.

The cautionary aspect of this is to be reminded, yet once again, to not be in too much of a hurry.  It’s clear to me from other contexts that when I rush things, I make mistakes.  And if I’m aiming to be professional in my maps, then that means slowing down, taking a breathe and double-checking things again.  And again.  There’s nothing worse then hitting send, or submitting that essay, and then realising there’s a mistake in there that you simply can’t undo.

Let that be a lesson to you – it certainly has been to me.  Now I’ll just check those maps one more time…

C

• October 5, 2018


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