Ocean Watch

Several people commented on my arowana column last week, and I learned that not all these fish cost a fortune.

"You can get small ones for about $100," my dinner party hostess told me last weekend.

"They get more expensive as they get bigger."

I discovered color means a lot, too. The red ones seem to be the most prized. One Asian store ranks their red ones as grade 1 and grade 2. "Grade 2 is more cheaper but less beautiful," says the store's Internet ad. Another online fish merchant offers arowana for $19.95 and up.

A reader e-mailed me that someone appears to be raising arowana in a public pond on Oahu. The reader enjoys watching this beautiful and graceful swimmer, but when the fish grows big, a curious thing happens: It disappears. Whoever removes the large fish replaces it with a small one, and the cycle begins again.

About my Jan. 6 column on how we perceive risks, I wrote that traveling a mile by bicycle is 14 times as likely to be fatal than traveling a mile by car. Ed, an Oklahoma instructor of the League of American Bicyclists, wanted to know where I got those figures.

The numbers came from a British study, via an article in Popular Science magazine about risk assessment. Here in the United States, according to National Safety Council figures posted on a University of Pennsylvania Web site, the risk of dying during a bike-mile versus a car-mile is worse than in Britain: 15 to 1.

Ed wrote me that a study he read concluded that cycling is less risky than riding in a car on a per-hour basis. Another reader, William, felt that I should have used surfing as an example of risk-taking, since some people have no other means of transportation than their bicycles.

"I think it was Harry Truman who said there are lies, damned lies, and statistics," Ed e-mailed back. We agreed that risk is all in how you look at it, my point in mentioning bike-riding at all in a column about sharks.

Another e-mail came from Victoria, a mystery writer. I'm guessing Victoria is from the mainland because she wrote to ask if Hawaii hosts any toxic fish. Victoria needs to poison a character in her story, set around the year 1400.

I told her about pufferfish, which contain one of the most potent poisons in nature, tetrodotoxin. Eight people in Hawaii have died from eating it.

Victoria didn't need the science on this subject to be too detailed, she wrote. She just wanted enough accuracy so someone like myself would not be pulled out of the story saying, "This could never happen!"

That reminds me of another e-mail that came out of the blue last week regarding my comments about the 2002 film "Whale Rider." The marine biology in it was so wrong, I wrote, that I couldn't stay in the movie.

"To start worrying about what type of whale it is just misses the whole point altogether," wrote Chris from New Zealand. "What you have taken far too seriously is yourself."

Oh, well. Victoria knows what I meant.

Thanks, everyone, for writing.