Sydney Harbour, Berrys Bay. 7 June 2013.
See Google Earth 33°50'39.79" S 151°11'44.85" E

Info from BR_Reef with thanks :

(L) KOALA

Main engine: 1 x 8 cyl GM Detroit 8V-71 diesel, 239 bhp/1800 rpm.

Built 1945 by Howard Moffatt & Company, Pyrmont NSW. 25 grt; standard dimensions : 45'0 x 14'8 x 5'9ft.

Standard 45 ft wooden towboat, designed by the Australian Shipbuilding Board; built to the order of the Australian Ministry of Munitions, Small Craft Construction Directorate; completed as US ARMY WT107 KOROWA (S-454) for the US Government.

(R) SYDPORT

Timber hulled; 31 grt; 13.72 x 4.42 x 2.65m; 1 x 6 cyl GM Detroit 8V-71, 239 bhp/1800 rpm.

Designed by A N Swinfield; built 1961 by Ballina Slipway & Engineering Co, Ballina NSW, for Harbour Lighterage Ltd, registered 8/5/1962 at Sydney.

AMSA data :
O.N. 316107 ... Length : 13.72 m
Year built : 1961 ... Type : Tug
Home port : Sydney

For starboard side pic of Koala (not a nautical name!)
See http://www.shipspotting.com/gallery/photo.php?lid=1815634
For Sydport underway (note people size for scale) ]
See http://www.shipspotting.com/gallery/photo.php?lid=1704732#