The Great Eggcase Hunt has landed on Australian shores, calling on citizen scientists to help researchers learn more about sharks, skates and chimaeras by finding and recording eggcases found both underwater and washed up along our coasts.  

CSIRO, Australia’s national science agency, is calling on citizen scientists to find and record eggcases seen on dives as well as those found washed up on Australian coasts, so researchers can better-understand egg-laying sharks, skates and chimaeras.

The Great Eggcase Hunt, an initiative of UK-based charity The Shark Trust, has launched in Australia in partnership with CSIRO to help provide new data for scientists studying the taxonomy and distribution of these sharks, skates and chimaeras.

Helen O’Neill, CSIRO Australian National Fish Collection biologist, said recording sightings of eggcases on beaches and coastlines would help scientists discover what the eggcases of different species look like, with some still unknown.

“Eggcases are important for understanding basic biology, as well as revealing valuable information such as where different species live and where their nurseries are located,” Ms O’Neill said.

Cat Gordon, Senior Conservation Officer at The Shark Trust said the Great Eggcase Hunt began in the UK 20 years ago and has since recorded more than 380,000 individual eggcases from around the world.

“We’re really excited to be partnering with CSIRO to officially launch this citizen science project in Australia and to be able to expand the Shark Trust’s eggcase identification resources. There’s such a diversity of species to be found around the Australian coastline, and with a tailored identification guide created for each state, they really showcase the different catsharks, skate, horn sharks, carpetsharks and chimaera eggcases that can be found washed ashore or seen while diving,” Ms Gordon said.

Also known as mermaids’ purses, eggcases come in many different shapes and colours, ranging from cream and butterscotch to deep amber and black. The range in size from approximately 4 to 25 centimetres.

Some eggcases have a smooth and simple appearance, while others have ridges, keels or curling tendrils that anchor them to kelp or coral. Port Jackson sharks have corkscrew-shaped egg cases that they wedge into rocks.

“At the Australian National Fish Collection, we are matching eggcases to the species that laid them,” Ms O’Neill said.

“We borrow eggcases from other collections, museums and aquariums around the world and use our own specimens collected from fish markets, from surveys at sea or extracted from the ovaries of preserved specimens in our collection,” she said.

Eggcases found on beaches rarely contain live embryos, whose incubation times range from a few months up to three years, depending on the species. However, if they’re seen in situ while diving, they may still contain a live embryo and so these eggcases should not be picked up or disturbed – if you can, take a photo and submit that along with your sighting when you’re back on dry land.

The Shark Trust is a UK-based charity dedicated to safeguarding the future of sharks, skates, rays, and chimaera through positive change. The Trust achieves this through science, education, influence, and action.

To get involved in the Great Eggcase Hunt, you can record sightings via the Shark Trust citizen science mobile phone app or through the project website www.eggcase.org.

Oceania has a fascinating mixture of well-known romantic destinations and wild, remote dive spots that few people ever get to visit. It is a region of contrasts with enough dive destinations and cultural highlights to satisfy even the most adventurous divers. In part II of 12 great places to go diving in Oceania, we take a deep dive into some of this region’s most famous and little-known islands. Get inspired for your next dive trip to Oceania here.

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French Polynesia

French Polynesia’s Society Islands have a stellar list of dive destinations, including Tahiti and Moorea. Between them, they offer easy coral reef diving and calm, turquoise lagoons with friendly stingrays and blacktip reef sharks. You can also swim with humpback whales, tiger sharks, lemon and nurse sharks there.

This beautiful nation’s best-known dive spots, Fakarava and Rangiroa atolls, are just a short flight away from the Society Islands. Both of these huge atolls offer exciting pass dives with hundreds of grey reef sharks and resident dolphins.

For a completely different dive experience, visit the Marquesas Islands. This island group is the farthest from any landfall on Earth and has a unique underwater world that hosts unusually large mantas and melon-headed whales.

And if that all sounds like too much effort, go Bora Bora scuba diving instead. This ‘Pearl of the Pacific’ has fantastic diving, and you can spend your downtime relaxing with champagne lunches on deserted islands.

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The Solomon Islands

The Solomon Islands are a haven for more than 1000 reef fish species and numerous prized critters, plus dolphins, sharks, rays and six species of sea turtle. Hosting hundreds of wrecks and remote hard coral reefs, there is something for every diver there.

The Russell Islands host some of the best-known dive sites in all of the Solomon Islands. There, you can glide between the walls of a crevasse that cuts through an island, immerse yourself in wreck diving at White Sand Beach, swim through a halocline at Custom Caves, or go in search of pygmy seahorses.

For the best wreck diving, make sure you visit Iron Bottom Sound. This stretch of water hosts around 200 ships and more than 600 aircraft wrecks from World War II. It is a wreck diving mecca that offers excellent tech-wreck dives.

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The Marshall Islands

The Marshall Islands is a chain of volcanic islands and coral atolls that few people know about. As the fifth least visited country in the world, these islands offer remote diving among exciting deep wrecks and vibrant coral reefs.

Bikini Atoll is the main dive destination in the Marshall Islands. Made famous by US atomic bomb tests in the 1940s, this atoll hosts numerous deep wrecks that offer incredible tech diving.

As well as some of the best tech-wreck dives imaginable, the Marshall Islands also have thriving hard coral reefs without any dive crowds. There are pinnacles, drop-offs, channels and shallow coral gardens to explore, busy with colorful reef life.

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The Cook Islands

When it comes to warm welcomes, it’s hard to beat the Cook Islands. From the moment you arrive, you will be drawn into one of the friendliest nations in the world and won’t want to leave.

This wonderful country is a perfect place to get your Open Water Diver certification or take your family diving. Rarotonga is the main destination for tourism and is a charming island with fresh markets, cafes, restaurants, and resorts tucked away among the palms. There are around 25 dive sites just offshore and gorgeous beaches for laid-back surface intervals.

Nearby Aitutaki has fewer visitors, yet it hosts around 22 dive sites, with many still being discovered. It is a great place to dive among remote coral-covered landscapes and forget the rest of the world exists. Whichever island you choose, the waters are warm and full of colorful reef life.

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New Caledonia

New Caledonia is one of those wish-list destinations known for its spectacular diving, crystal-clear waters and abundant marine life. Unlike some remote destinations in Oceania, New Caledonia has modern infrastructure that makes it easy to explore at your pace – by car or island hopping with regular domestic flights.

There are over 100 dive sites scatted around New Caledonia, offering a tempting mix of deep drop-offs, thrilling drift dives, wrecks, and easy reef diving. Most diving is conducted at the New Caledonia Barrier Reef, a vast 1500 km-long reef that encloses a UNESCO World Heritage lagoon. Within the lagoon, you can explore coral-encrusted walls, channels, and easy dive sites in shallow waters.

New Caledonia’s extensive marine reserves ensure these dive sites are teeming with life. For the best chance to see mantas and sharks, visit from April until September.

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Vanuatu

Vanuatu is the perfect place to reconnect with nature, offering untouched rainforests, natural swimming holes and excellent scuba diving.

Pristine reefs abound in Vanuatu, with many dive sites accessible simply by walking off the beach. Million Dollar Point is one of the most unique dive spots and hosts an array of machinery and equipment dumped by the US after World War II. The SS President Coolidge, a former World War II troop carrier, and the 1874 three-masted Star of Russia are excellent wrecks to dive.

The amount of marine life at Vanuatu’s dive sites is staggering. As well as rainbow-hued corals and countless reef fish, there are sea turtles, sharks, rays, and numerous pelagic fish. You can also go swimming with dugongs there.

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Papua New Guinea

Papua New Guinea is one of the most culturally diverse countries in the world, home to more than 850 known languages and hundreds of different tribes. It is unlike anywhere else in Oceania.

Along with the Solomon Islands, Papua New Guinea has some of the healthiest coral reefs in the world, including at Kimbe Bay. This special bay was once ranked as the most beautiful reef by National Geographic.

The nearby Witu Islands are a great place to go critter hunting and drift dive among schools of tuna and barracuda. Milne Bay is the home of muck diving and offers excellent shallow muck and reef diving with numerous critters.

There are seamounts busy with reef sharks and exciting walls at Fathers Reefs, and you can dive in the shadow of jungle-covered fjords at Tufi.

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Kathryn Curzon, a shark conservationist and dive travel writer for SSI (Scuba Schools International), wrote this article.