Here is a list of the largest flocks seen of various Australian bird species.
This could be birds at roost, where I’d expect flock sizes to be large.

Some of these are quite plausible.
Others are obviously errors.
For example nobody would see a single flock of Great Bowerbirds containing 1,900 birds

Which other ones are obvious errors? Or push the bounds of credibility.

Could a flock of roosting swallows be that large? 4,800 birds?
What of Plumed Whistling-Duck? 3,500 in one flock?
Could a roost of Rainbow Lorikeets contain 2,000 birds?
1,000 White-throated Needletails together?
1,000 Kelp Gulls?

mollwollfumble said:

Here is a list of the largest flocks seen of various Australian bird species.
This could be birds at roost, where I’d expect flock sizes to be large.

Some of these are quite plausible.
Others are obviously errors.
For example nobody would see a single flock of Great Bowerbirds containing 1,900 birds

Which other ones are obvious errors? Or push the bounds of credibility.

Could a flock of roosting swallows be that large? 4,800 birds?
What of Plumed Whistling-Duck? 3,500 in one flock?
Could a roost of Rainbow Lorikeets contain 2,000 birds?
1,000 White-throated Needletails together?
1,000 Kelp Gulls?

The list lacks lots of descriptives.

Budgerigars: up to 60,000.

https://www.australiangeographic.com.au/news/2012/11/biggest-budgie-flocks-in-a-decade/

Michael V said:

Budgerigars: up to 60,000.

https://www.australiangeographic.com.au/news/2012/11/biggest-budgie-flocks-in-a-decade/

A boomerang would get quite a few.

roughbarked said:

Michael V said:

Budgerigars: up to 60,000.

https://www.australiangeographic.com.au/news/2012/11/biggest-budgie-flocks-in-a-decade/

A boomerang would get quite a few.

You’d need quite a few for a feed.

mollwollfumble said:

Here is a list of the largest flocks seen of various Australian bird species.
This could be birds at roost, where I’d expect flock sizes to be large.

Some of these are quite plausible.
Others are obviously errors.
For example nobody would see a single flock of Great Bowerbirds containing 1,900 birds

Which other ones are obvious errors? Or push the bounds of credibility.

Could a flock of roosting swallows be that large? 4,800 birds?
What of Plumed Whistling-Duck? 3,500 in one flock?
Could a roost of Rainbow Lorikeets contain 2,000 birds?
1,000 White-throated Needletails together?
1,000 Kelp Gulls?

Thanks Michael V. In the survey I’m looking at, nobody was in the right position at the right time to reliably count more than 200 budgerigars in a single flock. I imagine that it would be difficult to count budgerigars in a large flock.

I’m going to mark only three of the above as errors.

Welcome Swallow. 4,793 is too big for a single flock.
Great Bowerbird. 1,927 is too big for a single flock.
Kelp Gull. 1,000 may not be too big for a breeding colony, but other indicators suggest that this is not a count from a breeding colony.