Hi Martin,
Not sure whether anyone replied to you on this, but on BirdLife Australia’s website has the Working List of Australian Birds (www.birdlife.org.au/conservation/science/taxonomy) that has a column with what were the old Atlas numbers, (Column D marked as “SpNo”).
Cheers, Sean
From: Birding-Aus <> On Behalf Of Martin Butterfield
Sent: Tuesday, 23 October 2018 1:27 PM
To: birding-aus NEW <>
Subject: [Birding-Aus] Checklist and species codes
Many years back Birds Australia used to publish (on their website) a checklist of species including reference numbers. These numbers included the latest official taxonomic codes and the codes used in the original Atlas. I can't currently find such a checklist on the BA site. Does it still exist somewhere (and if not, why not)?