Article extracted from Asian Diver Issue 01/2018 (149)

Text by Ocean Ramsey

Images by Juan Oliphant

TO LOCK EYES with a great white shark, watching it gracefully yet powerfully swim in from my periphery directly towards me, is an experience that no words can describe. Every year, I work with the white sharks that aggregate to feed on seals and sea lions around Isla Guadalupe, Mexico, under One Ocean Research, a group of marine biologists based in Hawaii. We set receivers and tags to gather data on the movements of white sharks in the area.

If a tagged shark swims within a kilometre of an underwater receiver, it will record the number code of

the shark’s tag. Before deploying a tag, the shark is photographed on its left and right side and filmed for ease of comparison between males and females, adults and juveniles. Whenever possible, we also work with charter boats that take tourists to see the white sharks and utilise their images to look for the occurrence of some of these tagged sharks outside of the receiver area.

I work with Dr Hoyos, who has dedicated his life and professional career to studying the white sharks of Isla Guadalupe in Mexico. Dr Hoyos has been working and tagging sharks in Isla Guadalupe for over 15 years. Sometimes, Dr Hoyos and I will do 24-hour tracking of certain sharks to record their movements in real-time with our GPS and a VR100 device that shows their current depth and the external temperature being recorded by their tag.

The role of sharks in the oceans’ ecosystems is to pick off the dead, dying, weak, sick, or injured in order to keep lower trophic level populations healthy and in balance. With over 400 million years of evolutionary history, sharks can quickly home in on which way you are facing and decipher body movements. White sharks are very much intelligent enough to be able to tell the difference between us and a natural prey item 99.9% of the time. However, it is unwise to push them in their territory, so the number of dives with them are limited and kept strictly to scientific purposes.

White shark individuals are easily identified by the distinct pattern across their gills. This is where the white of the underbelly meets the dark silver of their dorsal colouration, forming a pattern across the gills that is like a fingerprint for sharks. Working with professional photographers who shoot in high resolution allows us to zoom in on the images and videos to examine small details like tumours and other morphological scars and features.

Biopsies of skin and muscle tissue samples are sent to a lab to look at the genetics and stable isotopes. Muscle samples give us insight into the types of prey the shark has been consuming while examining the skin can identify distinct genetic codes that can be compared to the samples taken from pups that are caught near the continent to see where possible pupping grounds are. At this point in time, no person has ever been able to record a white shark giving birth and pupping grounds are still theoretical. We hope that a better understanding of the movements of white sharks can help support conservation efforts to expand protection for them.

Unfortunately, white shark populations around the planet are dropping and the iconic species is disappearing. White sharks are very slow to reproduce, they pup a few young, and we don’t know how many of their pups actually survive to adulthood.

I’ve been seeing many of the same larger individuals every one to three years over the last 10 years at Isla Guadalupe – a testament to just how few individuals there are in the area. The photo identification record for Isla Guadalupe has only around 200 individuals, and many juveniles are not yet of reproductive range, and may not survive long enough to reproduce due to the high chances of being caught in nets, longline fisheries, killed for sport or for shark’s fin soup – the number one reason sharks are being killed around the planet.

You can help save white sharks by supporting good scientific efforts, but more so by supporting good legislative action to better protect them and also by making daily consumer choices that don’t support the killing of sharks.

Like what you’ve read so far? Check out our LIVE! Panel Discussion on the Shark and Ocean Conversation today, 8 October 2020, at the following times: 

Singapore – 8PM / Sydney – 10PM / New York – 8AM / London – 1PM / Paris – 2PM / Tokyo – 9PM / Mumbai – 5.30PM / Sao Paolo – 9AM

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Article extracted from Asian Diver Issue 02/2017 (145)

Text and images by Dr. Richard Smith

THE DISTRIBUTION OF MARINE SPECIES is not the same between different areas of the ocean. Richness differs dramatically between regions due to the many pressures that have moulded each community over millions of years. The world’s highest marine biodiversity is found in a relatively small area known as the “Coral Triangle”. The Coral Triangle encompasses six countries – Malaysia, Indonesia, East Timor, Philippines, Papua New Guinea and the Solomon Islands, which together form a roughly triangular shape. The further you travel from the Coral Triangle in any direction, the fewer the number of marine species. So, unsurprisingly, it has been the main hub of recent marine discoveries. 

Very similar to an amphipod named after Sir Elton John in 2015, this amphipod is likely to be a new species.

CALAMIAN ISLANDS, PHILIPPINES

This small group of islands off the northern tip of Palawan in the Philippines has offered up a number of new discoveries over the years. It accommodates two of the three known damselfishes that lack a pelagic larval phase and another has recently been discovered from the same area and is in the process of being named. Damsels lay their eggs onto the reef and generally then guard them. Whilst the fry of the other 380 or so damselfishes then float off in ocean currents to distribute far and wide, these three subsequently guard their young, which stay in a small group around their parents. As a result they never get the chance to reach another reef, and the species has become trapped only around these few islands.

LESSER SUNDA ISLANDS, INDONESIA

The island chain that spans from Bali in the west to Timor and Tanimbar in the east has been rich in new discoveries. The islands in the chain are very close to each other – the next island in the chain is almost always visible – but deep oceanic trenches separate them. Strong currents flow through these trenches and impact heavily on the free movement of animals across the channels. As a result this has been a hotbed of diversification and many new discoveries have been made in this area. Several small bottom-dwelling sharks such as the Bali and Alor catsharks have been discovered in recent years, as well as the Indonesian wobbegong shark. Several new flasher wrasses have also be found here, including Renny and Alfian’s flashers from Komodo and Alor, respectively. 

TRITON BAY, INDONESIA 

Triton Bay was first explored in 2006 by scientists who had been titillated by other areas of the Bird’s Head. They found this to be another endemic-rich area, with several species found nowhere else on Earth. Jamal’s dottyback and Nursalim flasher wrasse are two of the most charismatic, discovered in 2007 and 2008 respectively. Jamal’s is a small, but locally common species that mimics the black bar chromis, whilst the Nursalim is as flashy and stunning as you’d expect for a flasher wrasse. Another dottyback that is very rarely seen, and was only named in 2008, is the zippered dottyback. They are found at the very limits of recreational diving. It has been suggested that two large river outflows on the boundaries of the bay act as freshwater barriers to the spread of these marine species. 

RAJA AMPAT, INDONESIA

Raja Ampat was the first of the Bird’s Head’s three main regions to be prospected for new species. Funnily enough, Raja Ampat was the site of many historical species discoveries. The blue-finned trevally and black- tipped reef shark both have their type specimens recorded from Raja Ampat a couple of hundred years ago. Along with an outstanding number of known species, in fact the most of any coral reef in the world, there were many new discoveries when scientists rediscovered the area over a decade ago. The ubiquitous Ammer’s dottyback was named in 2012 after the diving pioneer of this region, Max Ammer. 

CENDERAWASIH BAY, INDONESIA 

In 2006 Cenderawasih was visited for the first time by ichthyologists. They were shocked by the number of new discoveries they made during the trip. The huge bay has been periodically closed off due to ice ages and tectonic plate movements. These effectively isolated the animals in the bay and over time they evolved into new species, ripe for discovery. A glut of new species was named from the bay in the past decade, including Walton’s flasher wrasse, Cenderwasih fairy wrasse, Caitlin’s dottyback and Cenderawasih butterflyfish. Just last year another endemic, Maurine’s demoiselle, was named after Maurine Jones in honour of her work conserving the Bird’s Head. 

Like what you’ve read so far? Check out our LIVE! Panel Discussion on the Coral Triangle in Indonesia: The Paradise Paradox tomorrow, 27 August 2020, at the following times: 

Singapore – 8PM / Sydney – 10PM / New York – 8AM / London – 1PM / Paris – 2PM / Tokyo – 9PM / Mumbai – 5.30PM / Sao Paolo – 9AM

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