(Bloomberg)—America’s second-largest mall operator has a message for department stores leaving its malls: See ya, wouldn’t want to be ya.

News that Macy’s plans to close 100 stores, or 14% of its fleet, sparked fear of other big chains such as Sears and J.C. Penney following suit. That could create a glut of vacant mall space, which might be bad news for malls that house such anchor chains. Macy’s is No. 6 in the Internet Retailer 2016 Top 500 Guide.

General Growth Properties, however, implied at a real estate conference this week that it would be just fine with Macy’s leaving some of its malls. In fact, it’s in discussions with Macy’s and other anchor tenants about which malls it wants the chains to leave. Sounds like a strange thing for a mall operator with Macy’s in about 70% of its malls to do, no?

In the traditional mall model, department-store anchors are the major drivers of traffic. That model is becoming obsolete, GGP explained. In fact, GGP said it can fare better when an anchor store like Macy’s leaves.

One reason: Close to zero new malls are being built these days, constricting the supply of real estate. That leaves growing, healthy retailers hungry for good space.

Smaller stores in groups often drive just as much traffic to malls as old anchor chains do. And these stores often pay more rent than the old anchors, which typically pay below-market rents, based partly on the outdated premise they’re the main traffic draw.

Smart mall owners are carving up the cavernous spaces that once housed massive anchor chains, filling them with two to five smaller, more productive retailers, such as Dick’s Sporting Goods (No. 62), H&M (No. 77 in the Internet Retailer 2016 Europe 500), and The Container Store Inc. (No. 316). They’re also giving more space to nontraditional tenants—upscale restaurants, fitness centers such as LA Fitness and Soulcycle and entertainment venues, including movie theaters and Dave & Buster’s.

Off-price retailers such as T.J. Maxx and Nordstrom Rack, once relegated to strip centers, are now invited into malls. So are grocery stores, whose mall locations seem to be drawing steady traffic.

GGP has redeveloped more than 80 vacant department stores since 2011. At Oakbrook Center in the Chicago area, for example, GGP is putting in restaurants where a Sears (No. 14) once stood. It replaced a Bloomingdale’s with Pirch, Aritzia, Boss, Lululemon Ahtletica Inc. (No. 96), and Tommy Bahama. And it took a floor of unproductive space from Neiman Marcus (No. 36) and put in a steakhouse and a bar.

The mall’s sales per square foot—one measure of productivity—rose 36% between 2010 and 2015 in 2015. Its anchor-store productivity rose 17% in the same stretch.

Of course, such redevelopment isn’t cheap, and mall owners often have to forgo up to nine months of rent in the process. GGP has spent $1.4 billion on redeveloping those 80 anchor stores. And an anchor store’s exit can trigger lease clauses that let other tenants break their leases.

But GGP said having a plan for replacing anchor stores helps convince other tenants to stay put. It said its investments in anchor redevelopment have generated an 11% annual return. And non-anchor sales have been stronger than anchor sales; as of March 2016, on a rolling 12-month basis, non-anchor sales were up 4%, compared to a 1.9% decline in anchor-store sales, GGP said.

The downfall of department stores leaves little choice for mall owners. To keep shoppers coming amid an ongoing plunge in retail traffic, mall operators have to think creatively about how to stay relevant. Sometimes that means thinking outside the department-store box.