Lemon Shark in black and white

Sharks

The Great Hammerhead Shark

First described in 1837 by the German naturalist  Eduard Rüppell, the great hammerhead shark (Sphyrna mokarran) is the largest of the hammerhead shark family and can reach a length of over 6m (20ft), although some specimens have been seen to be much larger than this. However, with overfishing, the great hammerhead is usually observed to be much smaller than this.

The salmon shark is a species of mackerel shark found in the northern Pacific ocean.

New research reveals life history of salmon sharks

As the saying goes, you are what you eat. Researchers at Stanford University's Hopkins Marine Station are using this adage to better understand the life history of the salmon shark. An important apex predator and cousin of the great white, this far-ranging species roams the entire North Pacific Ocean, from Alaska to the warm sub-tropics of Hawaii and the Baja Peninsula

Sensitive shark fins

Chris Avila, of Canadian Marine Aquaculture, described how he was trying to collect a 3mm DNA sample from each of the fins of a new shipment of sharks, a species of bamboo shark (Hemiscyllium halmahera).

They showed no signs of distress when handled and had not reacted to having their fins pinched lightly, which is a stress test done prior to the clipping. Nevertheless, Avila had lightly sedated them for the procedure.

The relative abundance of sharks was significantly higher in non-fished sites

Healthy reefs have more sharks

The present study examined shark distribution patterns, species-habitat associations, and marine reserve use with baited remote underwater video stations (BRUVS) along the entire Great Barrier Reef Marine Park (GBRMP) over a ten-year period.

Overall, researchers recorded 21 different shark species. The relative abundance of sharks was significantly higher in non-fished sites in the GBR Marine Park no-fishing zones relative to fished sites.

Great white sharks as scavengers

University of Miami scientists Dr Neil Hammerschlag and Austin Gallagher, in collaboration with Chris Fallows of Apex Expeditions, South Africa, observed the feeding activity around four dead whales that appeared in the False Bay region during a period of ten years. They concluded that such bountiful sources of energy-rich blubber may be a significant food source for the great sharks.



Mr. Bruce

Western Australia Shark Cull Rejected

The policy allowing for the culling of any sharks longer than 3m was introduced after seven lethal shark attacks in three years off West Australian beaches. WA’s government proposed the new program in an effort to keep beachgoers safe that involved setting out baited drum lines, which consist of a large baited hook attached to a buoy and an anchor to hold it in place, in designated zones along popular beaches with the intention of killing great white sharks, bull sharks and tiger sharks who were larger than three meters.

Malapascua Island: Where thresher sharks roam

As picture perfect as Malapascua is, in a nation of 7,107 palm tree fringed islands, 2.5km long Malapascua wouldn’t be on anyone’s radar were it not for the thresher sharks that treat the island like a spa. Each morning as the sun peeks over the mountains on distant Cebu, Pelagic threshers rise from the depths to be cleaned by reef fish along a deep ledge known as Monad Shoal.