Michael McFadyen's Scuba Diving Web Site
Home · Contact Me · Sydney Reef Dive Sites · Sydney Shipwrecks · NSW Dive Sites · Australian Dive Sites · Overseas Dive Sites · Dive Accidents and Incidents · Our Yachting Adventures · 4WD Trips · Weather · Search 22 November 2017 21:47
Navigation
Home

General
About Me
My Diving
FAQ
Downloads
Web Links - Dive Clubs
St George Scuba Club
Some of my Best Photos
Contact Me

Dive Sites
Sydney Reef Dive Sites
Sydney Shipwrecks
Kelly Talking on ABC Sydney about Shipwrecks
NSW Dive Sites
Sydney Shipwreck Summary
NSW Shipwreck GPS/Marks
Australian Dive Sites
Overseas Dive Sites
Aircraft I have Dived
Old Bottles

Dive Related Equipment
Shearwater Predator and Heinrichs Weikamp OSTC 2N
Uwatec Aladin Dive Computers
Apollo AV1 Underwater Scooter
Bauer Compressor
DIY Oxygen Stick - Nitrox
GoPro HD Hero Video Camera
My Camera Setup
Purchase of New Dive Boat
Our Dive Boat - Mak Cat
Our Old Dive Boat - Le Scat
My Dive Gear
GPS and Diving
Make Your Own Car Tank Rack

Marine Life
Rarer Sydney Marine Life
Bare Island Pygmy Pipe Horses
Bare Island Sea Horses
Bare Island Nudibranchs
Bare Island Marine Life
Encounter with Southern Right Whale and Calf

Other Dive Info
How Weather Affects Diving in Sydney
Visibility and Wave Averages in Sydney
Waves and Diving
Diving Weather and Sea Conditions
Tide Tables
Dive Accidents and Incidents
Dive Book Reviews
Site Map
Noel Hitchins 1951-2005
Lloyd Bridges - Mike Nelson in Sea Hunt
Our Yachting Adventures
Below is a list of links to the main pages about our yacht, Catlypso and our Our Yachting Adventures:
  • Purchase of Catlypso
  • Details about Catlypso
  • Cleaning/Repairing Catlypso
  • Our Yachting Adventures.
  • Login
    Username

    Password



    Forgotten your password?
    Request a new one here.
    Michael and Kelly's 4WD Trips
    Click here for a list of our Four Wheel Drive and Camping Trips.
    Current Kareela Weather
    A summary of the current weather conditions at our house at Kareela, Sydney, is below. Click here for more Detailed Diving Weather and Conditions. Weather from Michael McFadyen's Tempe Weather Station


    Conditions at
    23:49 on 23/1/17

     
    Temperature 25.6°C
    Humidity 65.0%
    Barometer 1003.4hPa
    Rate -0.3hPa/hr
    Wind Speed: 0 km/hr
    Wind Direction S
    Rainfall for Today 0.0mm
    Rainfall last hour 0.0 mm
    Rainfall last 24 hours 0.0 mm
    Rainfall at Start of Month 814.6 mm
    Rainfall this Year 827.0 mm
    Today's Extremes
    High Temperature 31.2°C at 15:48
    Low Temperature 20.9°C at 6:27
    Peak Wind Gust 0km/hr at 0:00
    Weather from Michael McFadyen's Kirrawee Weather Station
    Yesterday's Extremes
    High Temperature 27.5°C at 17:11
    Low Temperature 19.8°C at 6:29
    Rainfall at Start of Yesterday 827.0 mm
    Rainfall at End of Yesterday 827.0 mm
    Weather from Michael McFadyen's Tempe Weather Station
    Astronomical Data
    Sunrise 5:06
    Sunset 19:05
    Moonrise 1:09
    Moonset 15:04

    Home Brewing
    Click here for an article about Home Brewing.
    Sydney Dive Site Hints
    "Tiny baby Port Jackson sharks can be seen in October at Bass and Flinders"
    Port Arthur
    Michael McFadyen's Scuba Diving - Port Arthur, Queensland Great Detached Reef is located at the northern end of the Great Barrier Reef off Queensland, Australia. It is about 125 nautical miles (230 kilometres) from Thursday Island in the Cape York area (the pointy tip of Australia) and 75 nm (140 kilometres) from Lockhart River. The is 45 nm (85 kilometres) east-north-east from closest point of the Australian mainland, Cape Grenville. It is just over 4 nm south of Raine Island, the largest green turtle nursery in the world.

    Cape YorkCape York
    A chart showing the location of Great Detached Reef (bottom right)
    and Thursday Island (top left)
    Great Detached Reef - Port Arthur
    is located at the south-eastern corner of GDR Lagoon and is marked

    Great Detached Reef is a reversed C shaped reef made up of a number of separate sections. It is located a little off what is the main outside section of the Great Barrier Reef, although here that reef is merely a series of small bommies or reefs. Great Detached Reef is 11.5 nm from north to south and 8.8 nm east to west. The west (open) side of the reef has a series of bommies and small reefs along a large part of its length.

    There are only a couple of boats that travel to this area, one being Kalinda which routinely does full boat charters there in November and December. Another boat does some trips there and one more might go there once or twice a year.

    Kelly and I travelled here in November 2016 on Kalinda with fellow members of St George Scuba Club when we chartered the whole boat. We flew into Horn Island (next to Thursday) and started our trip from there.

    The Great Detached Reef has a huge lagoon. Port Arthur is located on the inside of the lagoon down towards the south-eastern corner. Its location is GPS S11Âș 47' 57.4" E144Âș 04' 17.8". The bottom is a very gradually sloping sandy/coral mix with lots of small and larger coral bommies. The depth is only 2.5 metres or so next to the reef and about 12 metres where the boat anchors. It is excellent for night dives.

    The name Port Arthur was given to it as there are supposed to be large numbers of convict surgeonfish (for non-Aussies, Port Arthur was the penal colony in Tasmania). However, we never saw one.

    Port ArthurPort Arthur
    A banded pipefishTwo more banded pipefish, heads top right

    We anchored in about 15 metres and we dropped to the bottom off the side of the boat and then headed south-east towards the shallower area. We dropped to nine metres and immediately saw the first of many small coral bommies. They range in size from 2 metres across to 5 metres. Most only come up a metre or two from the bottom, but some are a bit higher.

    As soon as we went to the first bommie we found a pipefish. These are banded pipefish (Corythoichthys intestinalis) I think. In some books another species was also called banded pipefish. Anyway, they were everywhere! I counted 19 on our day dive but none at all on the night dive. Looks like they must all hide during the night.

    Port ArthurPort Arthur
    I think this is a barrier reef anemonefishA green turtle we saw on the night dive

    We then went from bommie to bommie to the south, and then headed north back around a very large bommie that creates a canyon between the main reef and the bommie. The sand here is only 2.5 metres deep or so. We went around this and then worked our way south to the end of the bommie and then west back to the boat.

    I saw a few small sharks, some saw a leaf fish (lucky!) and plenty of small tropicals. There were plenty of surgeonfish, parrotfish and trevallies. I also saw a few lionfish. On the night dive I had a large green turtle come from out of nowhere and swim right up to me.

    Port ArthurPort Arthur
    A photo of the divers on the night diveAnother shot from the night dive

    There were also lots of different species of shrimp on the night dive, but they were impossible to photograph. There was also a parrotfish in a coocoon and a couple of silver-tipped reef sharks, one of which was quite large.

    We dived here in November, the water temperature was about 28ÂșC, visibility varied from 10 to over 20 metres (on the night dive). A really good dive site.

    Copyright © Michael McFadyen 1990 to 2017
    Non-commercial use of an article or photograph is permitted with appropriate URL reference to this site.
    Dive shops, dive operators, publications and government departments cannot use anything without first seeking and receiving approval from Michael McFadyen.
    This web site has been wholly thought up, designed, constructed and funded by Michael McFadyen
    without any help from the Australian Dive Industry since 1996!