September 2022 Mallacoota Bird report

 A pretty good month with semi-reasonable weather and migrant birds beginning to return.  In total 132 taxa were recorded during the month.  This is, as expected a decent increase on August 2022 but a slight decrease when compared to September 2021.

I have put a full list of taxa seen and some of their attributes in a Google Sheet.  Note that additional sheets therein contain summaries by category and migration status (see below for a summary of these items).

I don't have a single standout species for the month but will give a boost to the subfamily Sternidae (Terns).  They get this honour as a result of:

• 
  a very large flock of crested terns on a sandbank off Captain Stevenson's Point: at 1099 birds this was the 3rd largest counted in the District.  It is of some interest that nearly all the very large flocks (> 500 birds) in the area have been recorded since 2019.  I'm unsure whether that means there are in fact more Crested Terns in the area or whether we are becoming less conservative in estimation (the 1099 was counted off photographs rather than guesstimated in the field).  Following confusion over an image of Little Corellas I will make it clear that the colours in the following images are dots I applied during counting: they aren't roosting Rainbow Lorikeets.

• on the edge of that large flock were 3 White-fronted Terns, yet to make the move back to their breeding grounds in New Zealand.

• a noisy and spectacular bit of display flying by 3 Caspian Terns.  They have been recorded nesting opposite Captain Stevenson's Point and on the Goodwin Sands.

Categories of Birds

In terms of the broad categories of birds seabirds and "other smaller birds' were under-represented this month and "other non-songbirds", honeyeaters and flycatchers were over-represented.

Migration Status

This month I have done some analysis of the reporting rate of taxa by month to come up with a classification of the migration status of each taxon.  This is still, to some extent, a work in progress with my methods so far and a link to a list of taxa with their migration status in a Google Document.  A particular area of future work is to refine the months used to define the seasons more appropriately than a simple split into 2 periods on 6 months each.

The following chart illustrates the composition of September sightings for 2022 and all Septembers.  I note in particular that this suggests under-representation of Summer migrants: I suspect that is probably a simplification since the "all September" value will be overstated by single early arrivals.  

For future reports I will look at simplifying this chart by combining categories.