Love is in the sea
It's springtime and love is in the sea. It's Hot; the sea temperature that is. And after the romantic full moon rises, you have to be under the sea at night to witness the world's largest living organism, the Great Barrier Reef, undertake its annual reproductive cycle.
Only Scuba divers and those that have gills can witness this natural wonder as the corals release their eggs into the warm water, then rising to the surface like thousands of bubbles in a champagne flute.
Annual coral orgies, the simultaneous mass spawning of corals on the Great Barrier Reef were first observed scientifically in 1981.
Scuba diving the Great Barrier Reef during coral spawning is an amazing experience and to add to that experience, the coral spawn only at night,
Coral spawning is now the focus of international research, but nature cannot be totally predicted.
The process begins six months before when eggs and sperm begin to form inside the coral polyps. For spawning to take place, water temperatures must be at least 27 degrees.
However, corals need a specific cue so they can release eggs and sperm into the water at the same time. That cue is November's full moon and on the 2nd to 6th night following the full moon, the majority of corals spawn. This year, coral spawning is expected to occur around November 25, 26 & 27 (give or take a few days)
Spawning is timed to coincide with periods when there are minimum tidal movements, which allows the reproductive components time to find representatives from the same species and mix and match before being swept away. Some years there is 'split' spawn with corals in shallow warmer inshore reefs performing in November while those in colder waters on the outer reefs, spawn in December.
Corals make such an effort to spawn at the same time in order to increase opportunities for fertilisation. Mass spawning also overwhelms the appetite of predators. Developing larvae (planula) are swept off to begin new reefs. A planula attaches itself to a vacant patch of reef and starts to grow as the founder polyp for a new coral colony. Coral spawning is a once in a lifetime experience and the highlight of diving at night.
Turtle breeding
Although the whales have returned south, boaters still need to keep an eye out on the water as marine turtles have begun the mating phase of their breeding cycle. Turtles mate on the surface, and there are a fair few turtles in the area, so ensure you stay clear for their protection, as they may not be aware of your approach!
Marine Notices
Boat Haven Bay, (Muddy Bay), adjacent Airlie Bay: hazard to navigation, a lighted buoy Fl Y 3s is established in position to mark the drying wreck, a steel coral viewing vessel, situated just off the rock wall of the Whitsunday Sailing Club.
Boat Haven note: A meeting of the Proserpine Shire Council on June 9, 1960 approved the adoption of 'Boat Haven' as the name for the bay at the eastern end of the Town of Airlie, till then known as Muddy Bay. The idea was to rid that muddy bay of the stigma of the earlier name. Source: Ray Blackwood.
Dent Passage caution
Mariners are advised that vessels transiting Dent Passage off the western end of the Hamilton Island airport runway are cautioned about frequent day and night aircraft movements. Vessels with an overall height greater than eight (8) metres are advised to keep clear of the flight path zone during aircraft movements. A chartlet (Map S11-41 dated 8 November 2010) details 'distance from runway' and 'mast height' restricted areas.
AUS charts 252, 253 & 254
Fair winds to Ye!
Cap'n Dan