STOCKTON, Calif. — As more nontraditional food stores and specialty retailers enter the Northern California grocery scene, the fight for market share continues to heat up.

“It’s getting more difficult to fight for your slice of the pie,” said Ed Odron, owner of Ed Odron Produce Marketing Consulting, Stockton.

“There’s only so much food business in Northern California, and if somebody comes in and makes a change, everbody’s slice of the pie starts to change.

“And there are people here now that years ago weren’t in the perishable business, and one of them is Target. So are the 99 cent and Dollar General stores.”

The fight card also includes specialty retailers, such as Sprouts and Whole Foods, expanding their reach. Regional retailers, such as Santa Cruz-based New Leaf Community Markets and Woodland-based Nugget Markets, have opened new stores farther from their origin, not to mention ethnic retailers such as 99 Ranch Market and Rancho San Miguel Markets.

All of these are chipping away at what was once the primary domain of traditional grocery retail chains, including Raley’s/Bel Air/Nob Hill, Safeway and Save Mart/Lucky.

Odron said specialty retailers, and particularly New Leaf, know their customer base and have expanded into areas with those higher-end demographics, such as San Jose, San Ramon and Pleasanton.

Shoppers at New Leaf tend to seek quality produce that’s organic, locally sourced and verified free of genetically modified organisms.

“They’re playing directly to their market,” Odron said.

“They’re in very nice neighborhoods and don’t have to worry about Dollar General. They found who and what they want to be, and they do it very well.”

Target has remodeled many of its stores to include a grocery and produce section. Shoppers who may be in the store for toothpaste and school supplies also may pick up food items, taking away dollars that traditionally went to grocers, he said.

Although at the other end of the spectrum, Odron said Rancho San Miguel, 99 Ranch and dollar stores have done a good job focusing on their core — price-conscious customers.

One of the quiet success stories has been FoodMaxx, owned by Modesto-based Save Mart Supermarkets, Odron said.

The chain of about 50 warehouse-style stores caters to price-conscious customers with bare-bones shelving and displays and self-bagging.

“You don’t hear about them, but they compete very well with those types of stores, like Food 4 Less and WinCo,” he said.

Another company worth watching is Berkeley-based Grocery Outlet, which is up for sale and has attracted several private equity firms, Odron said.

As the big companies continue to duke it out, many of the smaller neighborhood markets appear to be holding their own.

Although the bulk of its business is foodservice, Orange-based Interfresh Inc. does serve a number of smaller independent retailers, many of whom cater to specific ethnic groups, said Cory Puentes, Northern California sales director.

One of their assets is they can react to market changes much quicker than larger chains.

If, for example, tomatoes are in heavy supply on Tuesday, Puentes said he can approach smaller markets about running in-store promotions during the weekend and move a lot of product.

But chains typically plan promotions several weeks out.

Because the smaller markets are more nimble, they tend to have a loyal customer following, he said.

“I think they really market themselves on the value, and they know who their customers are,” Puentes said.