Annual report: 2012 compared to 5 previous years

The following table summarises the number of species reported by month and year.

	2007	2008	2009	2010	2011	2012
jan		69	86	89	95	94
feb	59	74	71	88	89	96
mar	69	72	78	79	88	95
apr		65	71	79	75	93
may	61	65	82	80	80	80
jun	51	69	71	77	65	79
jul	54	58	66	77	78	87
aug	57	72	74	80	90	97
sep	67	79	86	86	101	98
oct	67	85	92	97	99	113
nov	73	84	106	96	108	106
dec	60	84	96	95	99	116

Looking at the 150 species which were recorded in the area in 2012 in comparison with  the previous 5 years a first comment is that 11 species were observed in this area for the first time in 2012.  These were

• Australian Pelican; Australian Spotted Crake; Banded Lapwing;Chestnut-rumped Heathwren; Golden-headed Cisticola; Great Egret; Hoary-headed Grebe; Intermediate Egret; Restless Flycatcher; Swamp Harrier; Wonga Pigeon.  

I will have already commented on some of these in the linked posts.  Most of the other species in the list are regularly seen in the COG Area Of Interest but - for unknown reasons -  have been a little reluctant to reveal themselves here.

Of the 155 species for which comparison is possible, 19 have been recorded in every month throughout the 6 years (obviously including every month of 2012) These are:

• Australian Wood Duck; Galah; Sulphur-crested cockatoo; Crimson Rosella; Eastern Rosella; Laughing Kookaburra; White-eared Honeyeater; Noisy Miner; Willie wagtail; Magpie-lark; Welcome swallow; Yellow-rumped thornbill; White-throated treecreeper; Common starling; Grey butcherbird; Australian Magpie; Pied Currawong; Australian Raven; Little Raven.

For the 118 species recorded in 2012 which changed the proportion of months in which they were  recorded 98 (83.1%) showed an increase in the number of months in which they were recorded and 20 (16.9%) showed a decrease.  I shall return to an analysis of those numbers below, but a reconciliation tree diagram may be useful:

The 27 species recorded in the prior 4 years which did not appear in 2012 were:  

• Emu: Chestnut Teal; Spotted Dove; Fork-tailed swift; White-bellied Sea-eagle; Whistling Kite; Grey Goshawk; Silver Gull; Glossy Black-Cockatoo; Little Corella; Scaly-breasted Lorikeet; Fuscous honeyeater; Scarlet Honeyeater; Crescent Honeyeater; Spotted quail-thrush; Rufous Fantail; Satin Flycatcher; Jacky Winter; Red-capped Robin; Horsfields Bushlark; Zebra Finch.

Most of these birds are not common in the Canberra region.  The possible exceptions are:

• Silver Gull (but only really common along Lake Burley Griffin: a habitat not present in this area); and
• Little Corella (a recent arrival in Canberra which does not yet seem to have spread to out of the urban area).

It is pleasing to note the inclusion of Spotted Dove in the list of "not reported species".  As the species is being reported increasingly frequently in the urban area of Canberra I fear it is only a matter of time before we get a serious invasion.  If anyone spots one of these pests, please let me know asap.

Increasing species

There are 30 species recorded every month in 2012 which have been omitted at least once in earlier months.   With a 6 year series of observations I regard the 13 species only omitted once or twice as observer error (in most cases the missing period is early in the life of the project whenI was the only observer!).   Most of the 17 other species in this group of 30 are cases where the increased number of observers in recent years has added to the completeness of reports.  This is particularly the case for Eurasian Coot now seen every month at one or more sites with suitable water.  A second species with an obvious explanation is Tawny Frogmouth, now reported every month from Whiskers Creek Rd since I am specifically searching on a daily basis for a resident family, while in the past observing these birds was serendipity.

At the other end of the spectrum 14 species were recorded in a single month in 2011 and  tend to appear in the list of 'increasers' as a statistical quirk since 1/12 > 1/46!  They are clearly unusual in the area and will not be considered further.

A group seen in  at least 6 months in 2011 for which an increase of at least 10% has been noted amounts to 47 species.  I can't offer a comment about all of these so what follows is 'picking the eyes out' of the list.

• Many raptor species are in this group.  Possibly the most spectacular increase is the Spotted Harrier  which is far from common in the COG area but after an initial sighting late in 2011 has been reported from the Hoskinstown Plain in 10 months.  A Black Falcon was first seen in 2011 and was reported in early 2012 and again in December.  Specific blogposts have been written about the influxes of Black-shouldered Kites; Brown Falcons; and Barn Owls. in 2011: the birds continued to be more evident through 2012, although Barn Owls were absent in the latter months.  (Presumably mouse numbers have declined with the drier weather.)
• A number of birds which include water in their habitat preferences are also included. The large White-faced Heron was an occasional visitor to the area in the past and a sighting of 4 birds together in 2009 was sufficiently unusual to get a mention in the COG Annual Bird Report.  This year up to 15 have been seen together on a Hoskinstown swamp.   That site is also responsible, in part at east for increased reporting of Southern Shoveller, Hardhead, Black Swan and Eurasian Coot.
• Eastern Yellow Robin is usually thought of as a bird of the damp gullies.  The wet conditions of late 2010 and early 2011 led to a pair taking up residence at Whiskers Creek Rd.  They disappeared in early 2012 but reappeared in Spring of that year.
• The group of birds which are adapted to grasslands have all been reported more frequently as a result of extra observer effort on the Plain.  This includes:
• Finches (Red-browed Double-barred and European Goldfinch and Diamond Firetail); 
• Skylark; 
• Australasian Pipit; and 
• Red-rumped Parrot

Decreasing Species

Only 6 species show a decline of >10%.  5 of these are migrants and an increase of 1 month of observations in 2012 would have moved these out of this group.  The most significant decrease is of Rock Dove: either 

• someone has had pigeon pie; 
• the local Peregrine Falcons and Brown Goshawks have been more active. or
• someone has recently started shutting the door on their loft!

Links to other sections.

Overview report, 2012 cf 2011, Breeding