They’re closer and earlier and bigger than normal.

The combination constitutes a stunner of a tight-lines jackpot for San Diego-based sports fishing vessels hunting prized bluefin tuna.

No one, it seems, can dream up a reason to feel blue about the unexpected blues.

“Two years ago, we didn’t started running until Memorial Day,” said Drew Card, captain of the Pacific Queen moored at Fisherman’s Landing. “Even then, you didn’t get into fish until about 200 miles out and then it would be slow. Our first tuna trip this year was March 31.

“People were writing all these April Fool’s jokes on our Facebook page about catching bluefin that early.”

For those who prefer their water salty and their work amid the waves, it’s like Major League Baseball bats crackling to life in February or NFL games cropping up in July.

Pockets of early bluefin popped up a year ago, but the combination of size, location and date borders on unprecedented. It’s pumping thousands and thousands of dollars into the industry at a time routinely reserved for maintenance and season prep.

“Normally, you first start hearing the long-range guys on bluefin — the five-day trips, maybe the end of May and into June,” Card said. “A half-day boat (that has to stay closer to San Diego), two or three weeks ago, had 4 or 5 bluefin. I’ve never heard of that. That’s crazy.

“I don’t remember the bluefin being that close. They were only 6 to 12 miles off the coast.”

Mark Gillette, the captain of Eclipse, said one of his recent trips off Ensenada, Mexico, produced 10 schools of bluefin in a single afternoon.

The warming waters of the past two years have tossed the ecosystem in a blender. The fishing calendar finds itself in frenzied acceleration.

“It’s pretty unique — especially the volume we’re seeing,” said Gillette, who has skippered for nearly 17 years. “It’s April, but if feels like summer out there.”

Gillette isn’t a scientist, but Dr. David Checkley is.

The professor at Scripps Institute of Oceanography is the director of CalCOFI, also known by the tongue-testing title California Cooperative Oceanic Fisheries Investigations. The group has studied and pondered marine happenings since 1949.

Checkley said a phenomena known as “The Blob” developed two years ago when a lack of wind allowed a large volume of water in the north-central Pacific to warm. Powerful gusts normally mix and cool things by bringing deeper water toward the surface.

Two years of The Blob — with apologies to the 1958 drive-in movie staple — were followed by recent El Niño conditions, creating a sustained period and area of warmer water.

Checkley said the temperature at the end of Scripps Pier on Thursday registered at 64.8 degrees. For context, that’s anywhere from 2 to 5 degrees warmer than normal. For context stacked upon context, Checkley said the past century of global warming has raised average water temperature “about 1.1 degrees.”

“So that’s significant,” he said.

The bluefin followed. The boats followed the bluefin. Cause, meet affect.

Card, of Pacific Queen, said word reached his boat that TopGun 80 at H&M Landing steamed on an exploratory trip in late March and caught “limits” — meaning two bluefin per license.

“I heard that and said, ‘We’re going,’ ” he said. “We put a trip online. It filled up immediately. We went out, and we had limits. It was nuts.”

In past years, Card’s boat often made its first tuna trip in early July. This year, the crew already has undertaken “five or six.” The Pacific Queen’s most recent trip to Mexico, about 40 miles down the coast, yielded 40 fish on a short-leash single day trip. The majority of the bluefin, Card said, landed in the 50- to 70-pound range.

The success continued. The financial dominoes tumbled.

“It’s a lot less stress this time of the year,” he said. “Typically, you’re waiting for the season to get going. By the time you get to the end of May, the money’s running kind of thin. The fact that we’ve been running this winter. We’re stoked.”

Checkley, the ocean expert, predicts that waters will cool by season’s end.

A period of La Niña, a phase of the tropical cycle that delivers colder water, is expected. That has the potential to cool down the hectic bluefin fishing, as well.

“I anticipate the water off San Diego will cool in the coming year,” he said. “Now’s the time to go (fishing). My guess, it won’t be nearly as good in six months. It might not be worse, but I wouldn’t put my money on it being as good six months from right now.”

No one needs to tell Gillette twice.

“When they’re here and biting,” the captain of Eclipse reasoned, “you go fishing.”