Big swings in major stock indexes have caused investors to seek more stable fixed-income investments, such as bonds, according to the brokerages.

"They've know they needed to diversify for a long time, but as long as the markets were doing well they put it off," said E-Trade's Liat Rorer, who heads the broker's securities business. "There's no question they had a bit of a wake-up call, which caused a big flight to quality."

Investors' desire for stability in their investments tends to grow with age. With millions of baby boomers nearing retirement, the brokerages have responded by hosting seminars nationwide aimed at helping map out new strategies.

Many investors appear eager for such advice. They're enjoying longer life expectancies — which means they're likely to need a more sophisticated mix of investments to provide adequate income.

Ken McCoy, a 58-year-old engineering manager from Redwood City, Calif., is just such an investor. He attended a recent E-Trade conference to determine how to adjust to a bear market.

Fear, he said, was the main motivation.

"This is the first time in my investment life that I've actually been concerned about the stability of the whole system — we could be on the verge of a serious financial meltdown, and I want to be prepared."