In the Chicago futures pits, prices of lean hogs are going belly up.

The 26% decline in prices over the past nine months has frustrated traders, farmers and meat processors, who have long anticipated a rebound. It also has shown little benefit to consumers, who still are paying record prices for pork chops or to snack on BLTs, as retailers are reluctant to discount pork products.

Those high retail prices are a big part of the problem, traders said. The high cost is deterring U.S. consumers from buying pork products as demand from places such as China and South Korea also slows. Also, supplies are likely to be more plentiful than usual thanks to the mild U.S. winter, which caused hogs to add on more pounds than usual.

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That has all combined to drive down lean-hog prices at a time when prices typically would be rising in the roughly $8.6 billion market. Summer is approaching and supplies of pigs typically dwindle at this time of year. As Americans dust off their grills and start perusing pork-loin recipes, prices typically head higher. U.S. wholesale pork prices typically rise about 20% from winter through late summer.

"We kind of strangled domestic demand," with high prices, said Dan Vaught, president of brokerage Vaught Futures Insights in Altus, Ark. But he sees the making for a rebound: Grocers eventually will start to discount pork prices to woo shoppers.

"At some point, the bacon market is going to catch fire," Mr. Vaught said.

On Tuesday, the price of a lean-hog futures contract rose 0.3%, to 80.25 cents a pound, compared with nearly 90 cents a pound in late February. Prices for pork cuts in supermarket refrigerators were up 3.4% in March from a year earlier, according to the Labor Department's consumer-price index, and remain near record levels.

A look at prices for sausage filler illustrates the decline. Those prices usually surge in early spring as baseball season gets under way and as stadiums and tailgaters cook up hot dogs and bratwurst. Not this year. A standard filler widely used by sausage makers, comprised of both meat and pork fat, recently sold for about 62 cents a pound in wholesale markets, where processors can buy raw materials for cash. This time last year, it sold for 80 cents a pound.

But retailers are keeping prices higher, in large part because some anticipate wholesale prices eventually will rise, said Jim Robb, director of the Livestock Marketing Information Center in Denver, a cooperative that includes representatives from academia, the government and the meat trade.

Costco Wholesale Corp. (COST) spokesman Jeff Lyons said retailers like Costco are loath to lower prices until they are sure they can make up for the discounts with higher volumes. Costco has discounted some popular pork ribs, Mr. Lyons said, though has offset that by keeping prices of loins and chops high.