Wednesday, April 01, 2009

New protective laws for the Great White shark

Great white sharks, seagrass in Tomales Bay and other parts of the aquatic environment off Marin's coast will enjoy more protection under new federal rules that took effect this month.

The National Oceanic and Atmospheric Administration, which oversees federal marine sanctuaries, developed the regulatory changes after years of study, planning and public comment.

As part of the changes, great white sharks are now protected from people who want to get a closer look at them. There is now a prohibition against getting closer than 50 meters - or 164 feet - of a white shark within 2 nautical miles of the Farallon Islands. The rule also bans the practice of using decoys or chum to lure sharks.

"We have had cases where people in vessels come charging up to the sharks, scaring them away from food they have just caught," said Mary Jane Schramm, spokeswoman for the Gulf of the Farallones National Marine Sanctuary. "These activities threaten the health of the species."

Tomales Bay's seagrass, which helps species such as herring, will get special protection. Seven buoys will be placed in the bay to protect eelgrass and other seagrasses so boaters do not drop anchor or moor over the areas, which can damage the grasses or prevent them from getting sun.

The grasses help trap sediment, reduce nutrients and pollutants in the water and improve water quality. Seagrass also provides important habitat for migratory birds, such as shorebirds.

Marin has two parks just a short boat ride away: the Gulf of the Farallones is a 1,255-square-mile area made up of tidal flats, rocky intertidal areas, wetlands, subtidal reefs and coastal beaches. The sanctuary is home to thousands of seals and sea lions, hosts great white sharks and the largest concentration of breeding seabirds in the continental United States.

The Cordell Bank Sanctuary sits beyond the Gulf of the Farallones, 52 miles northwest of Marin's coast, at the edge of the continental shelf. It encompasses 526 square miles. Endangered humpback whales, porpoises, albatross and marine species flourish in the marine environment. Part of the Monterey Bay Sanctuary also bumps up against coastal Southern Marin.

Other new rules for sanctuaries prohibit:

- Harmful discharges from cruise ships and other large vessels.

- Discharges beyond the boundaries of the sanctuaries that enter and damage the sanctuaries' resources.

- Abandoning vessels.

- Introducing non-native species.

- Disturbing or killing sensitive wildlife like marine mammals, seabirds and sea turtles.

"They have been working on the regulations for some time and put a lot of effort into it," said Terri Watson of San Rafael, executive director for the Farallones Marine Sanctuary Association. "I'm confident they heard all the issues from all sides."

Sanctuary officials will work with the U.S. Coast Guard as well as researchers to help enforce the new rules. Violations are subject to citations and fines.

"There are many things affecting the sanctuaries: tourism, proposals for wave energy, invasive species, oil spills, they need to be better protected," Schramm said.

Contact Mark Prado via e-mail at

Face to face with a Great White shark!

THIS is the moment extreme sports adventurer Paul Leneghan, of Laxey, came face-to-face with a great white shark off the coast of South Africa.

Paul, who was in an underwater cage in an area known as Shark Alley Gansbaai, near Cape Town, during a trip to South Africa, was travelling with his 15-year-old son, who, not surprisingly, chose to stay on dry land during this adventure.

Paul said: 'They tie tuna heads on to lines and bait the sharks to breach and snap at them just in front of you.

'But when it was our turn the tuna head bait was too close to the cage and when the great white closed his jaw on to what he thought was the tuna head he actually snapped shut on the cage!'

Paul added: 'It shook the whole cage with five of us in it – no problem. I was scared to bloody death, that was not in the script!'

In future, Paul hopes to swim with bull sharks.

Discovery of the fossil of the ancestry of a Great White shark

This four-million-year-old fossil has taken some of the bite out of the great white shark's supposedly menacing ancestry, a new study finds.

The specimen—which includes part of the spinal column, the head, jaws lined with 222 teeth—is the most complete fossil known of an ancient great white shark.

Scientists had long assumed that great whites—which can reach lengths of 20 feet (6.1 meters)—were close kin of the prehistoric "megatooth" sharks, frightening creatures that grew up to 50 feet (15.2 meters) long and had jaws more than 9 feet (2.7 meters) wide.

But a new look at the fossil suggests that great whites are more closely related to the less fearsome and smaller mako shark, which belonged to a genus that still exists today.

If true, megatooths and great white sharks may have hit jumbo size independently, said study lead author Dana Ehret, a graduate student at the Florida Museum of Natural History.

Competition between great whites and megatooths may have contributed to both species' growth, said Ehret, whose study appears this month in the Journal of Vertebrate Paleontology.

The well-preserved specimen, found in 1988 in southwestern Peru, was donated to the Florida museum in 2008.

"It's really outstanding—not like anything we've seen in the fossil record in the past," Ehret said.