Friday, January 4, 2019

December 2018

The month was not great for diversity with only 91 species reported,  This is the lowest total for a December since 2008 (when reports were based solely on my personal observations).

To try to get a handle on what is missing in action (MIA) I assessed the number of species in each category and how commonly species were recorded in December.

Species Missing in Action

I have used 9 broad categories to present my results.  For each category  I counted the number of species ever reported in December (158 species in total) and then the number of species recorded in December 2018.  The difference between the two values in the number of MIAs.  In the next chart I have shown the number of MIA species  and that number as a % of the total number in any December.

Of the 5 groups that are major contributors to MIA:

  • Waterbirds are expected to be missing as there was hardly any water in the area until mid-December;
  • Raptors would seem to be reacting to absence of prey due to drought; and 
  • the 3 other groups contain many insectivorous species an insects are also lacking this year (except flies and mosquitoes around our house).

Common-ness of observed species.

I counted the number of Decembers 2007 to 2017 - maximum of 11) in which each species was recorded.  This covered all 158 species seen in at least 1 December.  I then calculated the average number of Decembers for each category.  I then calculated the average restricting it to those species seen in December 2018.  An example may help to explain this:

  • For waterbirds the average number of Decembers in which species have been seen is 4.54 (many species only seen in 1 or 2 Decembers).
  • Of the waterbird species seen in December 2018, they have been seen on average in 8.08 Decembers.  Of the 11 species on the list 6 have been seen in 10 or 11 Decembers.
  • I thus conclude that it is mainly the die-hard residents that are around.
This is illustrated in the next chart.  The two groups with the highest 2018:previous indexes have red stars and the next two, blue stars.
It is noteworthy that all Honeyeater species have been seen in at least 1 December and a high proportion of them were seen in December 2018.

Unusual species

After last month’s spate of unusuals, December has been a bit more restrained.  A Brush Cuckoo in the Molonglo Valley, male and female Koels in Radcliffe and an Australian Bushlark on the Plain have been the least common species reported to me.  The Avocets and Stilts were at Foxlow Lagoon early in the month but disappeared when the lagoon reached capacity due to a downpour.  A couple of Stilts returned later in the month.

Breeding 

Quite a good haul with 15 species this month marked in red below)..  The Banded Lapwings remain, with young chicks, on the Plain doing a good job of camouflaging themselves in a muddy patch (thanks Garry for the photo).
A pair of Leaden Flycatchers were taking turns on a nest at the top of Widgiewa.

A Silvereye has a nest full of chicks on Whiskers Creek Rd.

Thanks etc

As we are leaving the area this will be my last post of a monthly blog.  Thanks to all of you who have provided me with observations over the last 12 years!  My email will still work if you'd like to share sightings or ask questions, but I won;t be updating my database!

The list

1  Waterbirds (pt 1):  (pt 2)(Pt 3); (Pt 4): Australian Wood Duck; Grey Teal;  Pacific Black Duck; Australasian Grebe; Hoary-headed Grebe; Little Black Cormorant; Little Pied Cormorant;  White‑faced Heron; Eurasian  Coot; Black-winged Stilt; Red-necked Avocet;  Masked Lapwing; Banded Lapwing; 

2 Birds of Prey:  Brown Goshawk; Wedge-tailed Eagle;  Nankeen Kestrel; Brown Falcon

3 Parrots and Relatives:  Yellow-tailed Black-Cockatoo; Gang‑gang Cockatoo; Galah;  Little Corella; Sulphur‑crested Cockatoo; Australian King‑parrot; Crimson Rosella; Eastern Rosella; Red-rumped Parrot

4 Kingfishers and other non-songbirds (Pt 1) (Pt 2) (Pt 3): Stubble Quail;  Common Bronzewing; Crested Pigeon; Tawny Frogmouth;  Common Koel; Horsfield's Bronze‑Cuckoo; Shining Bronze‑cuckoo; Pallid Cuckoo; Fan‑tailed Cuckoo; Brush Cuckoo; Laughing KookaburraSacred Kingfisher;  Dollarbird; 

5 Honeyeaters: Eastern Spinebill; Yellow-faced Honeyeater;  Noisy Miner; Red Wattlebird; Brown‑headed Honeyeater; Noisy Friarbird

6 Flycatchers and similar speciesRufous Whistler; Grey Shrike-thrush;  Grey Fantail; Willie Wagtail; Leaden Flycatcher; Magpie-lark;  Welcome Swallow; Fairy Martin

7 Thornbills, Finches and similar species (Pt 1) (Pt 2):  Superb Fairy-wren; White-browed Scrubwren; Weebill; White-throated Gerygone; Striated Thornbill; Yellow‑rumped Thornbill; Buff‑rumped Thornbill; Brown Thornbill; Spotted Pardalote; Striated Pardalote; Silvereye; Red‑browed Finch;  House Sparrow; European Goldfinch

8 Other, smaller birds:  White-throated Treecreeper; Black-faced Cuckoo-shrike; White‑-winged Triller; Olive‑backed Oriole; Masked Woodswallow; White‑browed Woodswallow; Dusky Woodswallow; Horsefields Bushlark, Skylark;  Australian Reed-warbler; Common Blackbird; Common Myna; Common Starling; Mistletoebird; Australasian  Pipit;

9  Other, larger birds: Satin Bowerbird; Grey Butcherbird; Australian Magpie; Pied Currawong; Grey Currawong; Australian Raven; Little Raven; White-winged Chough

No comments:

Post a Comment

I am very happy to receive constructive comments. However anything I deem offensive will not be published.