WELLFLEET, Mass — There’s no good spot on Cape Cod for dolphins to beach themselves, but on this cold, gray day a group of 11 has chosen one of the worst.

The remote inlet down Wellfleet’s Herring River is a place where the tides recede fast and far, and that’s left the animals mired in a grayish-brown mud one local calls “Wellfleet mayonnaise.”

Walking is the only way to reach the animals, but it’s not easy. Rescuers crunch through cord grass and seashells before hitting a grabby muck that releases a footstep with a sucking pop. One volunteer hits a thigh-deep hole and tumbles forward. Mud covers his face like messy war paint.

It’s a scene that’s played itself out all winter long, and scientists have no idea why. A year ago, the 11 dolphins that stranded themselves Tuesday would have been a remarkable number. Now they’re just added to an ever-growing tally.

In the last month, 177 short-beaked common dolphins have stranded on Cape Cod, and 124 have died. The total is nearly five times the average of 37 common dolphins that have stranded each of the past 12 years.

Workers at the International Fund for Animal Welfare, which has led the rescue efforts, tag and take blood from the stranded animals. Necropsies have been done on dead dolphins and a Congressional briefing was held this month in the push for answers. But researchers can offer only theories such as changes in weather, water temperature or behavior of the dolphins’ prey.

Geography may also play a role if the dolphins are getting lost along the Cape’s jagged inner coastline in towns like Wellfleet.

Wellfleet in mid-February feels like a place long emptied out after a dimly remembered party. A drive into town takes you past a closed mini-golf course, candy store and drive-in theater. A downtown road rolls past shuttered cottages and motel cabins.

But Wellfleet is a hot spot for the dolphin strandings, in part because of features such as Jeremy Point, a thin peninsula that blocks the way to Cape Cod Bay if the dolphins wander too far into the town’s harbor, as they did on Tuesday.

The rescuers make a quick assessment once they reach the animals.

One dolphin is dead, but the other 10 appear healthy, and some bang their tails in the shallows, struggling to move. Rescuers decide the best course is to wait for the incoming tide to free the dolphins so boats can try to herd them out of trouble. The only other alternative is hauling them to a waiting trailer, and open water. But the trailer is nearly a mile away.

Waiting has risks. Dolphins can’t survive long on land and there’s no guarantee the boats can push the dolphins on to safety.

“Now’s where we start crossing our fingers,” says the fund’s Brian Sharp as he heads for a boat.

Rescuers in orange vests and black waders work in pairs to move the dolphins on slings, bringing them closer together and pointed the right way.

“We’ll take advantage of the fact that they’re social animals,” said Kerry Branon, a fund spokeswoman. “We’re hoping if we release them together, they’ll stick together and then we’ll herd them out around the point.”

Not all the dolphins are on board, though. One drifts off to the left, where he could beach again. The manager of the stranding team, Katie Moore, slides over, grabs its dorsal fin, and gives it a push in the right direction.

“You’re going the wrong way, buddy,” she says.

The inlet continues to fill and the dolphins break into waters that are deeper than the rescuers can follow, but they’re in two groups. The IFAW’s boat eventually follows one pod and the Wellfleet harbormaster takes another. The noise from the motors pushes the dolphins ahead. So do acoustic pingers, devices that make a sound that annoys the dolphins.

From here, all the shore workers can do is await word from the boats, which will follow the dolphins until dark, if needed. The crew trudges off the beach and gathers later in a parking lot at the Wellfleet marina, where coffee and doughnut holes beckon.

Mike Giblin, muck still on his face, sits in his truck and explains why, at 64, he can’t wait to get an early-morning call asking him to volunteer to help the dolphins. The animals are special, says the retired high school teacher. He says the dolphins somehow know the workers are there to help. He’s certain.

Moore later smiles at the thought, but dismisses any mystical link with the animals.

“They’re wild animals,” she says. “This is not comforting for them. They don’t want to be touched.”

The day’s gray cold has soaked through Moore and she’s worn out. Help for her team is coming from different places; some workers Tuesday came up from a Virginia aquarium. But she says the pace of the strandings has been exhausting.

“We just don’t know when it’s going to end anymore,” she said. “That wears on people.”

But she’s been encouraged by IFAW’s success so far in getting dolphins back to sea.

“I think that as humans we have such a huge impact on the ocean environment and on these animals in other ways, that this is our opportunity to do the right thing.”

As Moore speaks, her eyes flicker out to the harbor, where she can see the harbormaster’s boat has led its group of dolphins to sea. But her agency’s boat is still out, and she’s unsure if those dolphins will make it, or simply beach again.

The dolphins would all eventually reach the bay. But on Tuesday it was too early for answers, and Moore wondered if she would soon be second-guessing her decision to let the tide free the dolphins, rather than her workers.

“Ask me tomorrow how I feel about that,” she said.

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.