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Dr. Rick Braley obtained a grant from Queensland Treasury Community Benefit Fund in September 2011 for designing and setting up two Snorkel Trails on Magnetic Island on behalf of TOBMI (Tourism Operators and Businesses Magnetic Island). Permits were granted to construct the trails from GBRMPA (Great Barrier Reef Marine Park Authority) at Nelly Bay and at Geoffrey Bay.

Trails launched on 18 August 2012

The Nelly Bay trail (near Base Backpackers) was installed on 4 June 2012 and the Geoffrey Bay trail was installed on 14 July 2012. The launch of the trails was on Saturday, 18 August, 11.30am on the beach at the Nelly Bay trail near Base Backpackers.

The Nelly Bay trail a 15-20 minute walk from the ferry terminal (or depart the bus at Base Backpackers) and the Geoffrey Bay trail is easily accessible from the terminal. Take the Gabul Way walkway from Nelly Bay to Geoffrey Bay and walk to the other end of the bay. The trails are an exciting addition to the existing opportunities for nature based tourism on the island.

The unique design of the trails incorporates surface floats which are close to points of interest and are noted on a waterproof swim card. The trails have become a 'must do' on Magnetic Island. In 2016 the Snorkel Trails were simplified with a single swim card for both trails and only surface floats for the location. Cleaning.of the floats and ropes are done with scrub brushes and paint scrapers about every 3 weeks.  I maintain these trails with helpers from Pleasure Divers and friends.

We can say that there are no other continental islands off Northern Queensland other than Magnetic Island where visitors can get to relatively cheaply by ferry, to see these magnificent animals just off the beautiful beaches. Both Base Backpackers Magnetic Island continues to sponsor the Snorkel Trails and along with Sealink ferries who helped sponsor the translocation of these clams.  There are two snorkel trails: one at Nelly Bay near Base Backpackers (5 surface floats) and one at Geoffrey Bay near the Wallaby feeding area and near the Moltke wreck (4 surface floats).


ABOVE: The giant cams Tridacna gigas can now be seen in the Magnetic Island Snorkel Trails.


ABOVE: The Magnetic Island Snorkel Trails have become a 'must do' for visitors.


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ABOVE: DL for the Waterproof swim cards. Cards are $5 with specific information about the trails  and can be purchased from 11 locations on the island as well as Sealink and Magnetic Ferries as detailed in the Magnetic Island Guide and Informer or at

Waterproof swim cards with specific information about the trails can be purchased for $5 each from 11 locations on the island  and 2 places in Townsville (SEALINK and Magnetic Island Ferries). Locations of where you can pick up your swim card are detailed in the free Magnetic Island Guide and the Magnetic Informer or at Just attach the wrist band and you are ready to go.


There is also a complimentary 'best practices for snorkeling' in seven languages for those who purchase the swim cards. The cost of the cards help TMI to pay annual insurance and maintenance of the trails.

The videos of the two trails taken on 12 August 2020 can be found at:



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ABOVE: View the Geoffrey Bay Snorkel Trail float system.

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ABOVE: View the Nelly Bay Snorkel Trail float system.

ABOVE: The giant cams Tridacna gigas can now be seen in the Magnetic Island Snorkel Trails.


While Dr. Braley and Dr. Andy Lewis were obtaining GPS positions for the surface floats at Geoffrey Bay they located a WW2 propeller and engine block which some locals had talked about.


Dr. Braley investigated the wreck and contacted Gregory Williams, RAAF, Canberra, and Peter Dunn of Ozatwar, and after several Townsville Bulletin news articles, the experts said it was the remains of a crash of a CW-22B Curtis Falcon, serial number 3771,on 5 December 1943.


American pilot Richard A. Sansing survived the ditching of this plane which had an engine failure. The cowl and propeller are fairly intact "...indicating that it was not under power at the time." See Ozatwar for more information.


ABOVE: Dr Braley and Dr Lewis discover a WWII propeller while positioning the snorkel trails.


Magnetic Island visitors are the luckiest snorkelers in the region following the introduction of 14 giant clams to the Snorkel trails on the island. 30+ year old aquacultured giant clams (~100 kg ea.) of the largest species of mollusc the planet has ever seen (Tridacna gigas), are now easy to see by snorkelers using the self-guided snorkel trails.


Dr. Rick Braley, one of the worlds’ authorities on giant clams had cultured these clams from fertilized eggs during his PhD thesis.  The clams have been held since 1990 at the opposite end of the island to the snorkel trails. The clams were moved into the trails and set in groups of five and three at Nelly Bay and four and two at Geoffrey Bay. 


The clusters of these clams are like ‘mimics’ of high density natural populations mapped on reefs of the northern GBR during Dr. Braley’s thesis field work. They are all tagged on the outside of their shells and can be observed and photographed by the public. They are one of the emblems of the GBR.


When Captain Cook first saw these massive clams he quipped “there is a cockle so large, two men can not eat one at a sitting”. However, poaching by foreign vessels of giant clams for their adductor muscle in the late 1960s-70s resulted in reduced populations or local extinction in some Asia – Pacific countries.


While poaching also occurred in GBR waters, the size of the reef still contained natural untouched populations. Following the poaching, this giant clam species has been on the CITES  Appendix 2 list of endangered species. 

Clam Death in Geoffrey Bay Snorkel Trail in January 2021 

Clam number 1 near surface float 2 at the Geoffrey Bay Snorkel Trail was first observed dead on 7 January 2021. 

This giant clam shell was aquacultured from eggs by Dr. Rick Braley in January 1986 at Seafarm Pty. Ltd., Flying Fish Point, near Innisfail.  This species (Tridacna gigas Linne’ 1758 ) is the largest species of bivalve mollusc that has ever existed in the fossil record. This batch of aquacultured clams had a tumultuous start as they survived Cyclone Winifred (1 February 1986) in an outdoor tank with a lowered salinity for over a week. About 15,000 seed were translocated to James Cook University’s Orpheus Island Research Station in June 1986 and used in experiments along with other batches reared there.  In 1990-1992 some specimens of this unique batch were permitted to be translocated to Magnetic Island whilst some were left to remain with all other batches reared at Orpheus. 


In 2013 the Marine Park Authority permitted the translocation of 14 clams from the source clams on Magnetic Island to the two established Tourism Magnetic Island Snorkel Trails (6 at Geoffrey Bay and 8 at Nelly Bay). In February/March 2020 serious bleaching of corals and some clams occurred in the Snorkel Trails, and it took 2 – 2.5 months for the recovery of the symbiotic algal cells (zooxanthellae)

Boring sponge tubes in one shell valve reached the clam mantle tissue, being a factor in the death of this 35 yr. old clam. Dr. Merrick Ekins of the Queensland Museum (Brisbane) identified the sponge as Siphonodictyon mucosum Bergquist, 1965.  There is sparse literature on the chemicals they produce and how this may have affected this clam. The following measurements of the growth of the shell since translocation to Geoffrey Bay were: 13.6.13 – 62 cm shell length (SL); 6.5.15 – 65.5 cm SL, 26.12.15 – 66.5 cm SL; 10.6.17 – 72.2 cm SL; 31.1.21 – 76 cm SL. Weight 91 kg on 4.2.21.

Pleasure Divers has assisted Dr. Braley with regular cleaning of the snorkel trail floats, rope and annual maintenance checks. We are proud to display this shell at the Pleasure Divers  location, Arcadia, for the education of the public about giant clams, a threatened species worldwide.

ABOVE: Channel 7 TV news on 19 June 2013 reporting on the giant clams in the Snorkel Trails.

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ABOVE:  Giant clams 1 - 5 in the Nelly Bay Snorkel Trail.


ABOVE: Inside valve of clam 1, Geoffrey Bay Snorkel Trail. Note the boring sponge tubes with living dark brown tissue (Siphonodictyon mucosum Berguist, 1965). Photo taken by Dr. Leon Zann in situ before the shell was removed from the ocean and relocated to the Pleasure Divers location.


ABOVE:  Clam 1, Geoffrey Bay Snorkel Trail. Set in a concrete base at Pleasure Divers, Aradia. There will be an information plaque for visitors. Photo taken by Tom Gelling. 


This is home for Dr Rick Braley and his wife Nell. Magnetic Island is just 8 km from Townsville in North Queensland, but the island is very different from the mainland.


It is a landscape of hills filled with huge granite boulders, some just balanced upon other rocks awaiting their time to fall, beautiful beaches and woodlands, wildlife, and residential as well. 


The basic services of city water and electricity are run in pipes and cables along the seabed from Townsville.


Two companies run ferries daily from morning to evening from Townsville to Magnetic Island:

ABOVE: View the May 2016 Sealink video that includes a short piece of Rick showing his aquarium and talking about the snorkel trails.

Magnetic Island great barrier reef weddi

ABOVE: Magnetic Island is only 8km (25 minutes) from Townsville.


ABOVE: Magnetic Island has 23 bays and beaches and is surrounded by fringing reefs.

Would you like to know more about Magnetic Island?

For more detailed information about Magnetic Island visit
Tourism Magnetic Island, and

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