Mark Westbrook has lived on Hilton Head Island for nearly 30 years and can recall when local businesses shuttered their operations each winter until warmer temperatures replenished the town's population.
"Lots of restaurants and small hotels would just close," he said. "That's not the case anymore."
Business is still strongest in the summer months, said Westbrook, broker-in-chief of Resort Rentals of Hilton Head.
But the area is becoming increasingly popular as a temporary home in the wintertime as "snowbirds" from colder climates opt to spend up to three months in rented lodgings, he said.
"We're seeing a trend right now," said Westbrook, who estimated that his business's long-term winter rentals are up 15 to 20 percent over two years ago.
This year's influx of snowbirds is expected to be especially large, according to Westbrook.
"A lot of our business depends on the weather up North," he said. "Last year, they had a really long winter in the Midwest and Northeast, which should convince more people to come down here."
That might account for some sharp recent increase in winter reservations at Hilton Head Rentals & Golf, owned by Tom Ridgway. Reservations for the first three months of 2012 are up 43 percent over the same period in 2011, he said.
Visitors are staying longer, too; the number of reservations of two months or more in early 2012 at Ridgway's homes and villas are up exactly 100 percent over their 2011 rates.
Mike Alsko, general manager of ResortQuest Hilton Head Island, also reported an increase in snowbird reservations.
"Almost half of our rental properties will have guests who will be staying four consecutive weeks or longer this winter season, with an average length of stay for each reservation approaching 50 nights," Alsko wrote in a statement, adding that the figures were a "moderate increase" over their 2010 levels.
The annual winter pilgrimage isn't a new phenomenon, said Edward Dukes of Lowcountry Real Estate in Beaufort.
"We've seen a steady stream of visitors from October through April for a while now," Dukes said, adding that winter vacationers tend to stay longer than their summertime counterparts.
That's just one of several differences between the two groups, according to Bob Hawkins of the Vacation Company in Hilton Head, who said he's also seen a "considerable increase" in the volume of his winter rentals over the past few years.
Snowbirds, Hawkins said, tend to be older than summertime visitors, in part because families can't visit for as long in the winter because of school schedules.
They also tend to be slightly less affluent, he said, so they're attracted to rental prices that are lower than in the summer. And they're more likely to stay in their condos and villas and cook instead of visiting local restaurants.
"We have two divergent groups of people," Hawkins concluded, "that keep coming back to the area but enjoy it for different reasons."
Follow reporter Grant Martin at Twitter.com/LowCoBiz.