At the end of the Oak Bluffs ferry wharf early Sunday morning, seven-year-old Cameron Erich felt a tug on the end of his fishing line. He gripped the rod tightly, planted his feet and started reeling. His dad Cliff looked on proudly next to him.

“This is what we came for buddy,” he said as the fish emerged from the water. Cameron jumped up and down and let out a cheer while his father held the fish up high, illuminated by the sunrise.

“I’ve never caught a black bass that big,” said Cameron, who’s been fishing since age three. He turned around and dropped the line back in the water, eager to catch an even bigger one before the measuring station closed at 8 a.m.

Hundreds of kids and their parents lined the pier on the crisp, cool morning for the kids’ derby day, a part of the annual Martha’s Vineyard Striped Bass and Bluefish Derby. The ages of the young anglers ranged from four to 14 and fish are measured by length.

Tayla BenDavid with her 20-inch black sea bass took first prize in the 12-14 age division. — Mark Alan Lovewell

Cooper Gilkes, kids derby organizer of 37 years, said the derby is the only day during the year the pier opens for fishing and there’s no telling what the kids will yank out of the water.

“We’ve caught everything from a 200-pound blue shark to a two-pound lobster,” Mr Gilkes said. He added that black sea bass were the catch of the day so far, and pointed to long lines at the measuring table as a sign of a successful derby.

“I love to see the kids,” he said. “A lot of children catch their first fish out here.”

A crowd gathered and gasped loudly a the sight of a 21-inch sea bass caught by eight-year-old Liam O’Donnell.

“Whoa, look at this thing! You have to give it a kiss,” joked derby official Ron McKee.

“I thought it was stuck under the bridge, but it was just so big,” Liam said, with a wide grin.

Liam and his dad John walked over to the railing and tossed the fish back into the sea. The derby fish weren’t for keeping.

At first light, kids derby day delights. — Mark Alan Lovewell

“All right, let’s get going and catch another one,” said Mr. O’Donnell.

While Liam was an early frontrunner for biggest fish of the day, eight-year-old Chloe Cook was becoming a regular at the measuring table. Less than an hour into the derby, she had already reeled in a couple. A third was nibbling on the line.

“Woah, that’s a fish,” she said, leaning back to pull it in. “Wow, this one is strong. Wow, wow, wow!”

This time it was a black sea bass and her biggest catch of the day. Her dad Peter Cook helped her cut off the hook and drop the fish into a five-gallon bucket.

“Okay, my luck is never-ending,” she said as the fish attempted to jump out of its temporary home. “I just like fishing. It’s hard to fish and you meet a lot of nice people. If you’re lucky enough, you win!”

She walked quickly to the measuring table, bucket in hand, where Mr. McKee already knew her name. He held the sea bass down on the ruler and called out “Seventeen inches.”

Chloe gave her fish a name. “I named it Floppy,” she told Mr. McKee.

“All right,” he said with a laugh. “Now go get a bigger one.”

Results (all winning fish were black sea bass)

Overall

Liam O’Donnell, 21-inch

Ages 0-8

1. Finnegan Hall, 17-inch

2. Chloe Cook, 17-inch

3. Caleb Lucier, 16-inch

Ages 9-11

1. Nicholas Rabini, 15.25-inch

2. Aaiden Christensen, 15.25-inch

3. Eliot Davis, 15-inch

Ages 12-14

1. Tayla BenDavid, 20-inch

2. Riley Sylvia, 17.5-inch

3. Molly Sylvia, 17.5-inch