When Thomas Ronan started fishing the Martha's Vineyard Striped Bass and Bluefish Derby in the late 1980s, he never thought much about catching anything other than striped bass.

Bonito and false albacore were fun to bring in but their arrival in Vineyard waters was too unpredictable, and catching bluefish was too easy and ultimately got in the way of landing a striper. He really wanted to go after bass, especially the big ones, the kind that ended with an epic struggle and a feeling of real satisfaction.

Funny how the more things change over the years, the more they stay same.

"Now I like them all, but I still want those big bass," Mr. Ronan said this week during a brief break from fishing. "Now I'll go after what's running, but the bass are still the best."

This year, Mr. Ronan has his big bass - a 39.48-pounder - but his revised attitude about the other fish has landed him atop the leaderboard for one of the most highly coveted awards in the derby: the grand slam. In leading the competition for the heaviest combined weight of all four species of fish, Mr. Ronan's albacore (7.89 pounds), bass (39.48 pounds), bluefish (5.93 pounds) and bonito (5.71 pounds) are currently just over two pounds more than the second and third place entries. So far, his total is just over 59 pounds, a far cry from Lev Wlodyka's 76.98 pounds that won it last year, but still good enough for first.

"I don't think it's going to last too long if I don't get up there with a 10-pound bluefish or maybe a bigger bonito," he conceded on Friday.

For Mr. Ronan, that means a nerve-wracking run into October as fishermen with names like Jenkinson, Leaf and Plante breathe down his neck.

"I think I can find them," he said of the bigger fish. "I hope I can find them."

The grand slam has been called by many the real championship of the derby. Fishermen who go after it are rarely heard from or seen during the tournament's five weeks. They are known to fish from dawn until dark, and sometimes well beyond it. Families are left behind, jobs are abandoned, time washes away with the tides.

But the rewards can be worth it.

"Winning the grand slam," Bill Jurczyk said last year, "is like winning the green jacket at the Masters. It's a symbol of respect among the fishermen."

"In your peer community, you are raised up to a higher status, no question," said Jared MacKenzie, whose 10.38-pound boat bonito caught Sunday morning moved him into first place in that category. "The guys who fish hard know what kind of sacrifice you make, in terms of your wife, kids, job. It's completely consuming."

Mr. MacKenzie should know - he won the shore grand slam in 2000, and has come in second and third in other years. He said winning it comes down to two things: knowing what's out there and putting in the time to catch them.

"I always had a strategy," he said. "I'd get out there at sunrise for the albies and bonito, fish until about 4 p.m., take a three-hour break to get fresh bait and maybe catch some sleep before heading out for stripers and bluefish. I spent 12 hours a day fishing, easy. That's what these guys have to do to win."

Even though Mr. MacKenzie isn't thinking about the grand slam this year ("Things change with a family," he said with a grin), he has paid attention to what the fish are doing and where they are biting - important strategies to winning.

"If you go after the grand slam, you gotta know when and where those albies and bonito are hitting," he said. "Most guys go after them right away if they are around in the beginning of the derby, because they can take off at any time. I think landing those are key."

For Mr. Ronan, he thinks the key lies in - what else? - the big striper.

"It's all about the bass," Mr. Ronan said. "If you have trouble catching the bonito or albacore then it can be a problem, but I think it's the big bass that will push you over the top. You land a 40-pound bass, it separates you from the pack. All you need are decent sizes in the other fish, and you'll be in the running."

And that isn't always so easy. Mr. MacKenzie recalled that the year he won the grand slam, it was the bluefish - perhaps the easiest of the four to catch - that eluded him.

"Bluefish are my nemesis," he said with a laugh. "I catch them when I don't want them, and when I need one, I can't find one anywhere. And sometimes an eight-pound blue can mean first place. Sometimes a seemingly insignificant fish is what wins it all."

As far as those bigger bass that were absent for the first two weeks of the tournament, Mr. Ronan said that last weekend he had a feeling that was about to change, and he was right. On Sunday morning Walter Kelly weighed in the second 40-pound striped bass of the tournament - a 41.58-pounder that landed him in first place in the boat division and displaced Mr. Ronan in the process. Three minutes later, Jeff Lynch strolled into derby headquarters with a 43.72-pound bass.

And on Monday morning, Keith McArt weighed in a 42.54-pound shore striper to close within two-and-a-half pounds of Leo Lecuyer, whose 45.18-pound fish has been in the lead since Sept. 13.

Kathi Pogoda of Edgartown continues to land some impressive fish from the shore. On Friday morning she weighed in a 12.19-pound false albacore, good enough for first place in the shore division. That albie joined her 5.65-pound shore bonito on the leader board, which is currently in third place.

But Ms. Pogoda's reign atop the false albacore leaderboard was brief. Dennis Gough weighed in a mammoth 16.71-pound albie caught from Memorial Wharf in Edgartown, putting him a comfortable four pounds ahead of Ms. Pogoda.

Weekly winners for the second week of the derby, from Sept. 18 to Sept. 24, were as follows:

All tackle boat bonito, Nils Leaf, 8.39 pounds. All tackle shore bonito, Berni B. Arruda, 9.53 pounds. All tackle boat bluefish, Hollis F. Smith, 13.43 pounds. All tackle shore bluefish, Michael L. Adams, 11.74 pounds. All tackle boat striped bass, Thomas J. Ronan, 39.48 pounds. All tackle shore striped bass, Josiah I. Sylva, 37.16 pounds. All tackle boat false albacore, Keith M. Ogren, 14.19 pounds. All tackle shore false albacore, Kathi M. Pogoda, 12.19 pounds.

Flyrod boat bonito, David C. Kadison, 6.59 pounds. Flyrod boat bluefish, Rebecca L. Webb, 7.96 pounds. Flyrod shore bluefish, Tom P. Zaffiri, 4.70 pounds. Flyrod boat striped bass, Arthur E. Crago, 21.76 pounds. Flyrod boat false albacore, David C. Kadison, 9.26 pounds. Flyrod shore false albacore, David Hunt, 10.24 pounds.

Junior all tackle boat bluefish, John T. Barlosky, 11.05 pounds. Junior all tackle shore bluefish, Leah Pachico, 6.63 pounds. Junior all tackle boat striped bass, Chris A. Morris, 16.88 pounds. Junior all tackle shore striped bass, James M. Gibson, 18.17 pounds. Junior all tackle boat false albacore, Sarah L. Kadison, 11.27 pounds. Junior all tackle shore false albacore, Ashleigh Plante, 8.45 pounds.