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The Shark Highway

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This is the inner edge of the barrier reef, which protects the lagoon from the surging ocean. Within it, the lagoon is nearly a kilometer wide, and rarely more than two meters deep. It has many special places, micro habitats, used by animals for different purposes--deep, barren regions where sharks go to rest, shallow areas of thick coral where the babies seek refuge, places where the currents balance creating ideal conditions for spawning fish, places of strong and weak current, favoured by different species, and many more. This channel within the shelf of the reef itself, is used as a highway by sharks on the move.

The Lagoon

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This is the view in the other direction, the lagoon where my sharks live. With the sky above, and the earth below, this thin skin of water holds a drama of life I have found nowhere else. Here follows photos of some of the other inhabitants of this magic garden, which forms the setting of my shark stories.

Stone Fish

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These three partly camouflaged stone fish represent the least of the reasons NOT to walk in sea water. If stepped on, their spines inject a poison that causes vomiting and possibly heart attacks almost immediately, along with pain so severe it makes it hard to think about what one should do. Walking on the sea floor, even in shallow waters, crushes and hurts animals, large, and small, with every step, without the person even being aware of it. Its best to put on mask and fins where the waves lap upon the beach, and float away through the inches-deep water looking, and not touching, after that.

Visible Stone Fish

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These stone fish had just moved so it was possible to see them. The first photo above was taken half an hour later, when their camoflaging process had begun. While they appear among the ugliest of fish, strangely, they are closely related to the lion fish, the most beautiful one, though its poison is more fatal.

The Fish Who Looks Like a Flower

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Amoung the most beautiful of coral fish is the lion fish, related to the stone fish pictured above. It is said to have developed its frilly beauty to impress its food, which consists of crustaceans. I often wonder what that tells us about crustaceans. Its spines, like the stone fish, bear a poison similar to that of the cobra.

Spotted Puffer Fish

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Yellow Puffer FIsh

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Butterfly

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Coral Fish

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The intricate coral is home to a multitude. Here a chichlid family shelters within its labyrinths.

Living Waters

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Any view in any direction reveals a myriad of life forms, so varied in size, colour, and appearance, that even the water seems to live.

The Sting Ray

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Sting rays roam the lagoon, poking about in the sand for food, which they locate using their electric sense. Thus they can often be found by the clouds of sand they raise. These creatures present an awesome spectacle of beauty and grace when they fly, their meters-long tail held elegantly at an angle behind them.

The Eagle Ray

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Rays are sharks with wings. The eagle or leopard ray also dwells in the lagoon where my blackfin sharks live.

The Coral Garden

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The lagoon where my sharks live is a coral garden of supernatural beauty. This coral formation is an example of the marvels to be found while roaming there.

Shark Attack Mania

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Shark attack mania is a major obstacle to shark conservation, and seems to be quite obsessive to some, though baseless, considering the facts.
When I first came to Polynesia, twelve years ago, my gardener, Katoa, was my only source of information about the startling shark encounters I experienced when out in the lagoon. He was the only English speaker I knew, having fled the Cook Islands when they became independent and married a Tahitian so he could stay here. So all his life he had fished in traditional ways off the islands of the South Pacific. The question of what to do about sharks was an important one for me, since sometimes they appeared very close and circled me when I was alone a kilometer from land, and all I knew about them was what I had learned from watching "Jaws." I would watch their smug little faces as they turned around me and on the first occasion, felt actually disappointed by the lack of interest the fish displayed in me.
Once Katoa spoke of being especia…

Lemon Entrees

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So much shark behaviour seems to depend on whether we can see them or not, my main example of that being the time my step-son climbed upon a coral, and instantly the blackfin swimming with us went to him and sniffed his legs, quite aware, it seemed, that having his head above the water he could not see her. This came to mind again last night when I was drifting at dusk sketching the fin of an unknown juvenile blackfin who was roaming nearby. A movement off to the side caught my attention and I saw a good sized lemon shark approaching, already only a few feet away. They always look incongruous coming through the narrow coral canyons, seeming as big as a baby whale, though they are really smaller than that. Not wanting to startle him, I waited, perfectly still, for him to see me. He had a white spot on the tip of his nose, and that dazzling lemon shark smile.
Once my husband and I decided to celebrate Christmas by going to the end of Tahiti. The landscape resembled gently rolling h…

Sharks: Wolves of the Sea

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When I came to Polynesia, I was familiar with Canadian wild animals and had no idea what to expect when I began to meet sharks while exploring the lagoon. After a series of odd experiences with them I set out to find out what they were really like as animals and individuals. The species I concentrated on was Carcharhinus melanopterus, the reef blackfin shark.
To see what each one was doing from day to day, I had to be able to recognize them. So I drew their dorsal fins on each side, then copied them into a book, along with a description and any other details. I soon had so many that I had to give them names just to be able to remember them all. My notes grew to hundreds of pages and dozens of tables, and by now I have identified more than six hundred sharks, and could recognize half that many on sight before a large fraction of them were finned (starting on my study group in 2003—see 'In Memory of Madonna'). I spent as much time as I could with them, bringing them treats now an…

On the gestation period of the blackfin reef shark, Carcharhinus melanopterus in waters off Moorea, French Polynesia

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Originally published in the Journal "Marine Biology" at:http://link.springer.de


Abstract
Underwater visual and photographic observations, over a four year period, monitored the presence of mating wounds on femaleCarcharhinus melanopterus. Mating begins in November and continues until the end of March as each female follows her own temporal cycle. Correspondingly, parturition begins in September and continues until January. Each female again mates 1.5 to 2.5 months after parturition, thus completing an annual reproductive cycle. The gestation period is 286 to 305 days, with slight individual differences. All resident sharks under observation followed this pattern. Evidence of reproductive events presented by transient females conformed with the pattern of the residents.


Introduction
The few studies postulating a gestation period for the reef blackfin shark Carcharhinus melanopterus have varied greatly in their conclusions. Based on an examination of embryo development, Melouk …