FW: On the subject of species records and observers

["Geoffrey Dabb via Canberrabirds " <>]

And now a common widespread species.  A comparison of records for different areas indicates, in my view, where you will find the most active recorders as well as giving some information about distribution, and of course where records can be best captured by a square.  A variable polygon of fixed area would be better, but too much work.  I believe ALA maps exclude records where there is poor information about location.  As Canberra is emerging as the recording capital of Australia, an attached image shows the process used here.

 

Fourth species

Canberra  73,886

Melbourne  55,340

Brisbane  49,799

Sydney  28,702

Perth  16,967

Hobart  16,049

Adelaide  10,166

Darwin  56

 

From: Canberrabirds <> On Behalf Of Geoffrey Dabb via Canberrabirds
Sent: Saturday, 27 September 2025 11:53 AM
To: 'Canberrabirds' <>
Subject: Re: [Canberrabirds] On the subject of species records and observers

 

As some of you might have feared, I have a couple more Canberra bird species.  Same procedure as before.  I should mention that Atlas of Living Australia brings together eBird and BirdLife Australia records and those in first RAOU Atlas and in many older sources.  As a guide to distribution, the earlier records are now tending to be overwhelmed by the huge numbers of eBird records, although you can select sources as well as particular decades.  I’ve used all sources, all years.

 

Second species

Not an urban species. The 50x50km square had to be placed carefully to capture enough records to put Melbourne at top of list.  (Compensation for the D’s poor AFL season)

Melbourne  5236

Canberra 4876

Sydney 3698

Hobart 157

Adelaide, Brisbane, Perth, Darwin all zero.

 

Third species

Brisbane 407

Canberra 332

Sydney 249

Adelaide 118

Melbourne 79

Perth 16

Darwin 4

Hobart 3

 

 

From: Canberrabirds <> On Behalf Of Geoffrey Dabb via Canberrabirds
Sent: Friday, 26 September 2025 5:20 PM
To: Canberrabirds <>
Subject: [Canberrabirds] On the subject of species records and observers

 

Using the Atlas of Living Australia, I made a 50km square for each of the eight State/Territory capitals. Each was positioned to catch most of the available records of this native bird species, while also taking in the relevant CBD.  This was the result  –

 

Brisbane 2203

Melbourne 1226

Sydney 966

Canberra 430

Hobart 154

Adelaide 49

Darwin 4

Perth 1 (museum specimen only)

 

Hints - As ALA records go, these are low numbers for a species, White-faced Heron for example having over 700,000 records. Most records of this species are near the capitals, presumably indicating acceptable habitat and following the rule that records generally come from the most convenient places for observers.  However, South Australia is an exception because most records (253 in one 50km square) were more than 50 km from Adelaide.

Which species?  Please don’t reply to list in case people want to think about it.

 

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