Cheryl-Samantha Owen

Published 28th November 2008

At the Southern tip of Africa a deadly game of cat and mouse is played out over and over again in the salty waters off the fabled Cape of Storms. Each Southern hemisphere winter, between May and September, the infamous white shark makes its appearance known through spectacular airborne breaches out of the inky depths around Seal Island in False Bay (Western Cape, South Africa).

It is well known that at Seal Island the white sharks patrol the breeding colonies of Cape fur seals and their general hunting strategy involves swimming at depth to launch ambush attacks on the seals above, whose dark bodies are silhouetted against the light of the ocean’s surface. However, the range of tactics used by both predator and prey in this game of catch and be caught - or miss and survive - have until now remained a mystery.

In a paper published in the October issue of the scientific journal Animal Behaviour a team of scientists from Simon Fraser University, the Save Our Seas Foundation (SOSF) and Marine and Coastal Management Branch of the Department of Environmental Affairs explain what variables drive the tactical decisions of both shark and seal. A seal’s swimming and foraging behaviour tries to minimize the risk of being eaten by a shark; dicing with death, their strategy is aimed at avoiding attack. The sharks patrol using tactics that maximize their chance of killing; driven by hunger their payoff is a calorific, blubber rich meal. Karl Laroche, the lead author explains, “The optimal course of action for either species depends on the other’s behaviour.”

The breeding colony at Seal Island has a year-round population of between 36,000 and 77,000 seals, made up of an age mix from pups to breeding adults. With both pups and adults travelling from the colony to feed in open water and returning to rest or nurse, the shark population, so it seems, is spoilt for choice. The team’s findings challenge traditional studies that consider predator and prey as uniform groups. Their study suggests that seals may not be equal players in the game, because seals of different ages exhibit a very different set of behaviours around Seal Island.

The seals, which may stay away from the colony for several days or even weeks, appear to be at most risk from shark predation in the area between the shallow waters adjacent to the colony and about a distance of 1,000m out to sea. Well aware of the seals’ movements, the sharks concentrate within several hundred metres of shore, and the seals, well aware of the risk, select the best movement tactic to run the gauntlet.

Both species base their game tactics on variables such as location, swimming depth, and the timing of departure and return. In addition, seals have another card up their flippers: the option to choose the size of group they travel in. Seals of all ages depart in large groups within two hours after sunset by porpoising in a southerly direction at the surface from the south side of the island. Group swimming ensures safety in numbers on departure, but because coordinating large groups requires synchronized timing and seals are solitary feeders they often return to the island alone or in small groups. Most adult seals choose to return to the island under the cover of darkness, swimming at depth to avoid being conspicuous at the surface.

The majority of pups return between 7 and 9 am, alone, around sunrise, over the deeper waters of the southern and western sides, and spend considerably more time swimming at the surface than the adults. The study revealed that it is precisely these variables that produce the greatest probability of attack. “It appears the pups do not account for risk in choosing their game tactics and the fact that sharks concentrate in the morning, mid-water, to the south suggests that sharks focus primarily on the seals playing a high risk game,” says co-author and SOSF scientist Alison Kock. The return movement of seal pups explains why shark hunting tactics seem more influenced by the riskier behaviour of pups than adults.

The question remains, with the stakes so high, why do pups play such a risky game? The scientists are perplexed. Perhaps, it is naiveté or a miscalculation of timing, or perhaps it is a trade off that avoids another risk. One thing, however, is for certain, white shark numbers at many locations are plummeting due to over-fishing, and it is studies like this one funded by the Save Our Seas Foundation that are essential for learning more about these apex predators before it is too late.

For more information on sharks visit: www.saveourseas.com

Published 21st November 2008

‘Rethink the Shark’ highlights the fact that faulty toasters kill more people each year than sharks do.

"It's very heartening this year to see so many films with a strong environmental focus – it seems at last the environment is going mainstream, and is on everyone's agenda," said Joanna Lumley, the host of this year's Oscars of the wildlife film industry.

The Gala Panda Awards in Bristol took place last month amidst a week of seminars, debates and discussion at Wildscreen, the leading wildlife film festival. It attracts delegates from around the globe who work in film, television and the press, as well as those actively involved in working to conserve the environment. Over 420 films were entered.

A definite buzz filled the air at this year's Festival and the big 'C' word was on the lips of most producers, commissioners, cameramen and NGOs.

A swear word on the tongue of some and the planet's only hope in the voice of others, the big 'C' in the wildlife film industry stands for Conservation.

Every film-maker wants the audience to care passionately about their story to the extent that they feel moved to take action and make a difference, but from Sir David Attenborough and James Lovelock to the Director of Google Earth, it seems everyone is perplexed as to why environmental films with strong conservation messages are not making it to the light of day.

Sadly, those that do are destined for the ghost slots, late nights on channel Z while prime time TV is sandwiched with big teeth, blood and fear.

One character that almost always comes worse off in these adrenaline documentaries is the shark. A never-ending series of natural history films (perhaps natural history entertainment is a more apt description) portray sharks as man-eaters.

By perpetuating the 'Jaws' myth these films do nothing to promote shark conservation and the cruel fact that man is killing 100 million of them each year, pushing sharks toward their final cut – extinction.

In one giant step towards promoting natural history films that tell the whole story and engage viewers with the big 'C', the Save Our Seas Foundation (SOSF) took home the most prestigious award in natural history filmmaking – the Panda Award – for its campaign film 'Rethink the Shark'.

A great campaign film considers the audience, provides a key message in a compelling way, and hopefully challenges preconceptions. According to the judges SOSF's 'Rethink the Shark' did this with "a sharp eye for detail, extreme wit and good humour."

SOSF, in partnership with Saatchi and Saatchi's Cape Town division of the global advertising agency, created a film that ends the stereotypical view of 'Jaws'- with an ironic twist.

Drawing from its scientists around the world SOSF's HD films are based on cutting edge research and designed to educate, delight and inspire the audience to take action and conserve our marine environment.

A summer's day on a crowded beach: shrieks of delight and joy sound the air as children splash and play in the ocean. The happy, family scene turns sour as a woman screams and panic ensues. People swim frantically for the shore, there is a stampede on the beach and a baby, almost trampled in the chaos, cries.

Am ominous shape appears – a toaster floats towards the panicked spectators, its triangular edge bobbing above the surface, and the audience gasps as reality hits the screen: "Last year 791 people were killed by faulty toasters. Only 4 by sharks. Rethink the Shark".

The film, part of an awareness campaign driven by the SOSF, urges people to 'Rethink the Shark'. It challenges the media-driven public perception of sharks as man-eaters to looking at these key ocean predators in their real light.

SOSF is a non-profit research and education organization that is dedicated to raising awareness about the state of our oceans and highlighting the negative consequences of removing sharks and rays from the marine ecosystem.

Cape Town, where the scene was filmed, is home to the Save Our Seas Shark Centre, which promotes the protection and conservation of sharks worldwide by developing scientific research projects and global education and awareness projects that target the general public, fishers and children.

So, next time you crisp your bread spare a thought for the sharks out there that are rapidly becoming toast due to over-fishing and finning.

For more information or to download 'Rethink the Shark' visit: www.saveourseas.com

Published 5th August 2008

Cool Seas Road Show Inspires Children to Care about our Oceans

Sea fever is rapidly spreading through the country’s school children. From Cornwall to Scotland, the Isle of Man to Ireland, kids as young as four years old are learning that British seas are just as cool as those in the tropics, in fact more so. I visited Andy Starbuck earlier this month to find out what the Cool Seas Road Show (CSRS) was all about, and arriving from a world of environmental doom and gloom, I left the classroom feeling inspired by the power our future generations hold to save our seas.

The Save Our Seas Foundation (SOSF) together with the Marine Conservation Society is a major sponsor of this inspiring initiative. SOSF implements and supports a diversity of scientific research and education projects focused on the marine environment, particularly focused on sharks and rays.

The CSRS is an educational presentation designed to raise public awareness of our oceans and the diversity of marine life off our shores. County councils encourage it as part of a greater environmental education program within local schools, and each council often emphasizes a particular theme, which Andy highlights in the Show. Priceless expressions of wonder and delight light up on both children and teachers as they enter their school hall filled with life-size models so life-like that they could be real were they moving.

Starbuck presents the Show several times a day at one school, adapting it in length and content for the different age groups. A prop maker for TV and theatre before turning his hands towards sea creatures, Starbuck makes and hand paints all the inflatable marine models used in the CSRS. The school halls are normally not large enough to accommodate all his creations, but on my visit he had managed to squeeze in more than even Mary Poppins herself could have managed. Included were a juvenile and adult bottlenose dolphin, a common dolphin, a porpoise, a minke whale, a grey seal with her pup, a leatherback turtle, turtle hatchlings, a basking shark and a great white shark!

The students were thrilled to learn that cold water harbours more variation of life than warm water, that all of these creatures live in British waters, and that there is a good chance that they could see some of them if they took the time to watch from their own town pier. Working his way around the hall Starbuck teaches the kids facts about each charismatic animal on display. Wide-eyed, the kids gasp at the size of a mother bottlenose dolphin compared to her small calf and learn to distinguish between the different species through their markings and dorsal fins. Starbuck encourages the children to reconsider their ideas of marine life, such as considering dolphins to be not so unlike us, mammals, rather than “fishy creatures.” The sharks are undoubtedly the boys’ favourites, but they were all surprised to learn that falling coconuts kill more people each year, and that even though one pupil could fit in its mouth, a basking shark is a harmless plankton eating fish. I talked to some of the pupils after each session and with over 100 million sharks killed each year by humans it was refreshing to see perceptions changed at such a young age. One boy announcing to me that he “was not so worried about sharks anymore!”

After being introduced to each species the students are taught how the animals depend on a multitude of smaller creatures, from smaller sharks and fish to jellyfish, plankton and algae, and that these are all needed to make up our amazing and complex cool seas ecosystem. Audience participation allows several children “on stage” to run through a series of role-plays, including acting out conservation workers helping turtles hatching. The pupils love it; they learn how vulnerable the hatchlings are and it illustrates how we can all make a positive difference towards saving our seas if we all work together.

The Show, however was not made in fairyland and the children are taught some of the adverse effects humans have on our blue planet, especially regarding litter. Analyzing a collection of plastic rubbish, including plastic bottles, bags and empty helium balloons, found on a nearby beach and explaining how it could kill turtles and dolphins, the kids soon realize that rubbish does not miraculously disappear.

During his two weeks in Brighton, Starbuck presented to 3,200 pupils, and in a typical year he presents to 20,000 children. “It is important to encourage the kids to carry on learning and to explore their own marine environment, and the experience lasts a lifetime,” says Andy. In fact Andy met an 18 year-old work experience student in one of the schools who remembered the CSRS at her school when she was only five. In addition, the Cool Seas books expose friends and parents to the cool seas, and the children take home a very powerful weapon: “Pester power”, which educates and coerces parents towards marine conservation and awareness.

Although 71% of our planet is covered in salt water and the UK is surrounded by this watery world, some children have never stuck their head beneath the waves, let alone understand that this fragile world goes far deeper than the visual, blue and grey rolling waves upon the surface. “The CSRS enables kids a hands on exploration of a world that is for most part, off limits; this helps kids experience, understand and gain a greater appreciation of the marine environment, which is why SOSF is proud to be involved,” says Chris Clarke, director of the SOSF.

For more information on the marine environment visit www.saveourseas.com

A second, and possibly third, species of manta ray has been discovered in the World’s oceans. This is the biggest news to date to come out of ray research, and its importance is the marine equivalent of discovering an unknown species of elephant. The discovery however, has implications that go far beyond the breaking news of scientific journals, as it will deeply affect real world conservation ideas and policies.

For the past five years the Save Our Seas Foundation (SOSF) has sponsored Andrea Marshall, a PhD marine biologist in a quest to make advances in the scientific knowledge of these winged beauties of the sea, whose large triangular pectoral fins can span almost 8m in width and whose weight can reach over 2000kg. Manta rays, which are totally harmless and do not possess a stinging barb, are the largest of over 500 different species of rays and skates, and although divers have noted variations in physical appearance they were previously believed to be the same kind.

After suspecting the existence of a second species Andrea began studying other populations across the globe. Through genetic and morphological analysis she confirmed that there is indeed a second, and possibly a third, species of manta ray that exists across temperate, tropical and subtropical waters worldwide. The two species have mainly overlapping distributions, but their lifestyles differ greatly; one is migratory and the other is resident to particular areas along the coast. Other differences between the two species lie in their colour, skin texture, reproductive biology, and the presence of a non-functioning type of sting on the tail of one of the species.

The smaller, more commonly known manta ray, resides in the same areas year round and is often encountered at coral reefs where they congregate to be cleaned by parasite-eating fish in locations such as Hawaii, the Maldives, Mozambique, Australia, Japan and the Island of Yap. Due to their residential nature they face a grave threat from unsustainable fisheries, as other manta rays will not replace a dwindling population, making their regional extinction a likely possibility.

Far less is known about the larger species, as it appears to be more migratory and elusive, shying away from divers rather than seeking interaction as its smaller cousin often does. Andrea has only ever witnessed it arriving at sea-mounts or at particularly productive areas along the coastline to feed on plankton before disappearing into the blue once again.  Little is known about its behaviour or migratory patterns, though it appears to be targeted heavily by fisheries, particularly in Southeast Asia, where thousands are killed each year.

The discovery of two distinct species has huge implications for the conservation management and protection of these mysterious gentle giants. The larger, ocean wanderer knows no borders, making collaboration between countries on its protection essential, whereas protective measure within countries must be enforced to avoid resident manta ray populations crashing. Habitat degradation, harassment by boat traffic and even divers who interact with them at critical habitats such as cleaning stations and breeding areas are other threats these graceful animals face. They also fall victim to ghost nets and are killed alongside many other marine creatures as by-catch.

Andrea’s obsession with sharks travelled with her from the tender age of five until university when she discovered how little was known about their cartilaginous cousins, manta rays. Undeterred by the difficulties such research would involve she sold her belongings and in 2003 moved to a small coastal village in southern Mozambique, to become the first marine biologist to study manta rays off the African coast. Through her observations of the unique spot patterning on the ventral surface of each ray Andrea has identified over 900 individuals on a single reef, and she believes southern Mozambique may boast the largest known population of manta rays in the world.

Discoveries about the reproductive behaviour of these highly social and inquisitive creatures have also been an important outcome of Andrea’s research. Manta rays are now known to give birth to a single large offspring of about 1.4m after a year of gestation and, once reaching maturity at about 4m across, typically produce a pup every other year. Elaborate and sophisticated courtship displays are performed and they may communicate with one another using specific body posturing and perhaps sound.

SOSF aims to learn more about the role of marine species, particularly sharks and rays, and through this knowledge it hopes to raise awareness and conserve the marine realm. Andrea’s many hours underwater have produced information critically needed for the protection of these threatened animals. We now know that there are at least two species, but we need to know a great deal more about their population structure and distribution so that we can devise and implement improved protection measures.