November 12, 2009--After 60 years in a watery Hawaiian grave, two World War II-era Japanese attack submarines have been discovered near Pearl Harbor, marine archaeologists announced today. (Watch video of the sunken subs.)

Specifically designed for a stealth attack on the U.S. East Coast--perhaps targeting Washington, D.C., and New York City--the "samurai subs" were fast, far-ranging, and in some cases carried folding-wing aircraft, according to Dik Daso, curator of modern military aircraft at the Smithsonian's Air and Space Museum, speaking in the new National Geographic documentary Hunt for the Samurai Subs.

Read More at National Geographic

A diver has captured on camera the moment he risked his life to swim alongside a 15m humpback whale in Hawaii. Marco Queral said he was cautious when attracting the female whale's attention last week, because one flick of its tail could have meant death. "They are usually more shy and cautious toward humans and boats ... perhaps because they are not so accustomed to seeing humans offshore," Mr Queral was quoted in the Daily Mail as saying. The 42-year-old has been swimming with dolphins and sea creatures for 17 years.

Check out the awesome photos here.

Laboratory mice injected with toxins from sea slugs found on an Auckland beach died as scientists watched - proving the slugs are toxic, but not revealing what has made them so poisonous.

Scientists trying to discover what killed two dogs that died after walking on Narrow Neck beach believe sea slugs found nearby may have eaten something toxic, possibly algae, and passed on the toxins to dogs.

Cawthron Institute algae specialist Paul McNabb said the investigators made two important findings - that the slugs were toxic, and that the dogs' vomit was toxic.

Once they pinpoint the slug toxin, chemists will try to match it to the dog toxin. If the toxins are the same, they might be able to trace it to the ultimate source of the problem - whatever the slugs picked up in their environment.

Mr McNabb said chemists were trying to get "as far down the list as possible" of toxins by tomorrow, when health authorities are due to revise warnings against water sports and taking children to the beach.

If they had not identified a toxin by then, authorities would have to decide whether to approve "thousands of days" more of expensive tests.

Mr McNabb said the slugs were the only things taken from Narrow Neck beach found to be toxic, although seaweeds, sponges and a mixture of sand and algae were still being tested.

The stomach contents of pilchards, which have washed up in large numbers in recent weeks, were also being tested.

He said the toxic vomit strongly suggested the dogs died because of something they ate.

Councils and health authorities have stopped short of cancelling health alerts in the Hauraki Gulf until they know more.

A spokeswoman for the Auckland Regional Council, which is fronting efforts by eight Government and local agencies to find the cause of the problem, said further test results would be announced tomorrow afternoon.

The three grey sea slugs were collected from Narrow Neck beach last Friday but their bodies were in bits so biologists could not identify the species.

Mr McNabb said whole slugs would look like "shellfish without the shells" and would not necessarily be obvious to the naked eye if they were in dogs' vomit.

A dog would not need to eat a whole slug to become ill - picking one up in its mouth could be enough.

Unlike some tropical sea slugs, sea slugs found in New Zealand did not normally produce toxins, so it was more likely the slugs themselves had eaten something.

Niwa algae expert Dr Hoe Chang said sea slugs grazed on seaweeds and algal mats and could have been feeding on toxic algae.

But tests by him and the Cawthron Institute had not found any obvious species of toxic alga in the water.

Dr Chang said he initially thought an algal bloom was unlikely because most blooms in the past 20 years had been easily noticeable, usually turning the water brown.

There were no signs of a bloom this time, but algae could cause a toxic outbreak without reaching bloom levels.

A theory gaining currency among some amateur scientists - that the dogs were killed by fumes created when toxic algae are broken up by waves - was unlikely to be correct.

The species of alga that caused this type of effect, known as "toxic aerosols", had not shown up in any of the 21 water samples he had tested.

The worst-known effect of toxic aerosols was breathing difficulties, which disappeared once a dog or person left the water.

* The next steps

How scientists hope to find out what killed the dogs:

Identify the toxic chemicals in the sea slugs.

Prove the toxins are the same as those found in the dogs' stomachs.

Match toxins to something in the marine environment that the slugs have been eating.

Reporting Off Key Biscayne, Fla. -- With a spray of water, Guy Gleichmann surfaces from a 40-foot dive during which he helped set his mother's remains in their final resting place: a sunken city where brightly hued fish shimmy among fantastical architecture.

"I didn't want to leave," Gleichmann says, doffing mask and mouthpiece. "It's so beautiful down there. It's so serene." The 48-year-old investment manager and diver from Pompano Beach, Fla., wanted a unique and accessible spot for his mother, Emma, who died in December at age 75. So he had her cremated remains mixed into concrete in the shape of a seashell, which was placed near the statue of a lion.

Emma Gleichmann was one of nearly 60 souls whose cremated remains rest in nautical sculptures on the sea floor about three miles off Key Biscayne at the one-of-a-kind Neptune Memorial Reef. The alternative burial option creates an environment for reef creatures and a destination for divers. "It will always be a special place when I go diving, to come out here and be where she's at," Gleichmann says. "It just gives you a feeling that they're not totally gone."

The reef, a subsidiary of the Neptune Society, the nation's largest cremation company, opened in fall 2007 after four years of permitting hurdles. It encompasses 16 acres and features oversize sculptures: arches, columns, gates and benches, all designed by Key Largo artist Kim Brandell.

"I was trying to achieve some sort of sunken city, but not Atlantis," Brandell says, calling his architectural style futuristic rather than classical.

The scale is appropriately gargantuan for an undersea necropolis: 5-ton columns on 50-ton bases, arches soaring 25 feet. About a tenth of the underwater sculpture garden has been developed, says project manager Jim Hutslar. When the entire reef is completed, perhaps in 10 years, its rings and spokes will resemble a massive mandala. Leaping dolphins, chariots and Neptune himself are planned as future monuments.

In the company's Deerfield Beach plant, Hutslar mixes a client's cremated remains into special underwater concrete in 10-pound sculptures of starfish, shells and coral. Family members can watch or participate. Some place small tokens from the deceased in the mix -- fishing lures, angels or rosaries.

On the reef, the sculptures are affixed to pavers along paths or set into columns and statuary. They eventually will be covered with coral, but plaques reveal who resides there. The cost is $2,600 for a standard placement of cremated remains. A cremation and placement package runs about $4,000.

Appealing to sea lovers, the reef is home to the remains of boat captains and divers. Others desire a unique alternative to the graveyard. "We're seeing a lot of baby boomers because it's different," says Stephen Ziadie, Neptune Memorial Reef's chief operating officer.

Fish swarm there by the hundreds; an eel and two stingrays have taken up residence. "As I'm working, they're around my hands, trying to see what I'm doing," Hutslar says.

Of the 1,200 spots in the reef's initial development, more than half have been sold, he said. The company doesn't own the site -- it's in international waters -- but has federal and state permission to build on it.

Hutslar makes several maintenance dives to the reef each week, and places the remains of five to six people there a month. Nine family members of one woman learned to dive so they could watch him set her sculpture. "They all got certified for that one event," he says.

Ron Hink, 54, of Fort Lauderdale, suggested the reef for his mother, Edith, when she was in a hospice. "She just lit up and said, 'Gosh, I love the idea. I've always lived on the water, and I'll have waterfront property,' " he recalls.

Hink bought space in a column for himself, his wife and two kids. "One by one we'll all go there," he says.