Contrarian advice from hedge fund manager Bill Ackman, head of Pershing Square Capital Management: Buy mall REITs now.

At the beginning of the year, mall REITs operated in an economic environment world far more difficult that the one they experience today, Ackman told the International Council of Shopping Centers during a recent presentation titled “If You Wait For The Robins, Spring Will Be Over.”

“Retailers with successful concepts are acquiring leases from liquidating retailers, allowing malls to refresh their product offerings with concepts that should drive increased traffic,” he says.

Mall REITs’ leverage ratios “have decreased meaningfully” since last May, Ackman notes. Mall REIT cap rates have declined and should continue to do so, and rent relief is only 2 basis points of total revenue.

Add to that the fact that mall tenants are much better capitalized now and a University of Michigan study showing that consumer confidence is on the rise, and the list of reason to buy mall REITs grows.

Ackman also points out that REIT stocks are rebounding: The IYR REIT index has doubled since March and REIT CDS have meaningfully compressed year-to-date, enabling REITs to issue large amounts of low-cost debt and raise equity of $18 billion.

According to Daily Finance, many of the mall stores opening in 2010 to replace those lost during the recession will have an international flavor, as a variety of European chains are expanding rapidly into the U.S.