When bass season opens Saturday, anglers can expect to find largemouth, smallmouth and spotted bass with one thing on their minds: foraging.

Although a few aggressive males may still be guarding nests, most post-spawn bass in rivers and lakes will be preying on baitfish to nourish themselves.

"And to the anglers' advantage, they may be a little more naive because they haven't been fished over yet," said the Pennsylvania Fish and Boat Commission's chief warmwater biologist Bob Lorantas. "Just coming off the beds, they tend to be shallower, but lakes have already turned over and they could be just about anywhere there's cover and forage."

In 2007 bass density rankings, the Fish Commission rated Cross Creek Lake in Washington County the No. 1 mid-size bass lake in the state, while Kahle Lake in Clarion and Venango counties rated fourth. Lake Wilhelm in Mercer County rated fifth for large impoundments. The Youghiogheny, Allegheny and Monongahela were among the top five rivers. In 2007, Butler County's Lake Arthur produced two of Pennsylvania's biggest largemouth bass, including an 8-pound 2-ouncer, while Lake Erie yielded the state's five biggest smallmouths, all over 7 pounds.

Erie is where FLW Tour pro Dan Gray of Butler and BASS Open angler Ken Baumgardner of Monongahela each headed with friends last weekend.

"We sight-fished in the bay all day and it was really kickin,' " said Baumgardner, a veteran of the 2009 Bassmaster Classic. "Targeting the edge of the flats with creature baits, we caught 60 bass in five hours. Our biggest was 7 pounds."

Gray started his day in the bay, catching smallmouths on top-water lures and crankbaits just off the shallow flats, and largemouths flipping tubes about 5 feet into the weeds. He fished the main lake in the afternoon.

"We caught them in 7 to 12 feet on spinner baits and jerkbaits, and a few on tubes, looking for roaming fish. We're seeing big largemouths in the lake for the first time, too," said Gray, who tallied close to 60 releases with his partner in a day he described as "awesome."

Water in the lake was 58 degrees, about 8 degrees cooler than the bay.

"Bass can be on their spawning beds in the lake until the end of June," Gray said. "We've pulled them up from 30 feet with red tails or full of eggs, even into July."

Wherever he's bassin' at this time of year, Gray typically targets off-shore structure.

"I find post-spawn bass around rock piles, underwater stumps and lay-downs, as well as the edge of weed beds," he said. "Bass are backing off the shoreline to a little deeper water. I'll fish a jig or a tube on a flipping stick. I'll search areas with a square-billed crankbait that doesn't go real deep, or a Carolina rig that lets me cover a lot of water. If I locate bass, I'll switch to a little finesse jig to pick them apart."

Gray concurs that Wilhelm, Kahle and Arthur offer some of the best catches in the region.

"Kahle's crystal clear, so all you have to do is throw anything black ... jet black tubes, jigs or flukes," he said. "It has a lot of weeds, so target the weed lines, as well as the wood, the beaver huts and other hard spots."

And Pymatuning has evolved into a superstar, he said.

"It has so many bass, it's ridiculous. When I started fishing tournaments 10, 12 years ago, 12 pounds was a winning weight for a [two-man] 10-fish limit. Now a lot of tournaments have cut down to a seven-fish limit at Pymatuning and they're weighing 24 pounds." Because it's shallow, Pymatuning heats up quickly, especially on the north end.

"I'd already be progressing to top-water baits ... buzzbaits, spinnerbaits, crankbaits," he said. "I'd fish a lot of moving baits offshore."

Baumgardner's favorite lake is Raystown.

"You can get some jumbo bass in there. I'm talking over 7 pounds. They're nomads. They follow the bait," he said. "I usually stay with shad and alewife patterns because that's the forage there."

He also fished Loyalhanna Lake for the first time recently and was impressed.

"That place was kickin' really good," he said. "We caught 40-some largemouths up to 4 pounds one evening, all on creature baits."

And he said his home water, the Monongahela River, is productive.

"River bass are definitely structure-oriented right now, so the rocks along shore are a really good bet, and the grass is starting to come up now, too," said Baumgardner. "Smallmouths are the dominant species on all three rivers, and they're fattening up on crayfish right now. But spotted bass in the Mon are really taking off."

"Spots are aggressive, they're fun to catch and they school by size, so if you catch one 14-incher, you could catch 20," he said. "And they're eating any kind of plastics -- creatures, tubes, rubber worms -- rigged Texas style with the lightest weight the current will let you go with."