January -- typically a slow month for home sales -- had its highest total sales in the Bay Area in five years, according to real estate information service DataQuick, thanks to foreclosures and other distressed properties.

Buyers picked up 5,479 homes and condos in the Bay Area in January, DataQuick reported, a 10.3 percent increase from January 2011, but a 26.9 percent decrease from December, when sales are typically much brisker. The typical drop from December to January is 28 percent, DataQuick reported.

The median price paid for a Bay Area home dropped 2.8 percent from December, to $326,000, as more than half of resold homes and condos were foreclosures or so-called short sales. Homes that were foreclosed upon in the previous 12 months and short sales -- in which properties sell for less than what is owed on the previous mortgage -- accounted for 51.9 percent of resold homes in the Bay Area, up from 48.5 percent in December but down from 54.5 percent in January 2011.

"While it's clear prices have edged lower in some areas recently, last month's Bay Area median of just $326,000 is a reflection of how skewed the market has become toward distressed, lower-cost properties," DataQuick President John Walsh said in the announcement, while cautioning that "winter numbers are based on a smaller pool of buyers and they haven't proved very predictive" for the entire year's figures.

In January 2011, the median price paid for a Bay Area home was $338,000, but the average median price for the entire year was $390,000, DataQuick reported.

Alameda County had the highest number of homes sold in January, DataQuick reported, with 1,201 -- a 23.9 percent increase from January 2011. Buyers picked up 1,183 homes in Santa Clara County, a 4.3 percent year-over-year increase, and 1,115 in Contra Costa County, a 2.1 percent increase. San Mateo County home sales increased 17.7 percent from January 2011, to 438.

Sales were estimated in Alameda, San Francisco and San Mateo counties due to late data availability, DataQuick said.

Contact Jeremy C. Owens at 408-920-5876; follow him at Twitter.com/mercbizbreak.