BELGRADE — Abigail Mitchell, 11, stood in her grandfather’s motorboat and scanned the unusually calm waters of Great Pond with binoculars, searching with her sister and cousins for the telltale black head and neck with a slash of white of their target, an icon of Maine lakes, the loon.

“It’s fun to be the first one to find one. It’s like a game,” said Abigail, of Lowell, Mass., part of the fourth generation of loon-counters in her family. “And you’re with your cousins, so it’s fun just hanging out in the boat.”

Abigail’s grandfather, Chip Bessey, drove Abigail, her sister Casey, 10, cousins Jack, 8, and Morgan, 15, and their mom Jennifer Kidwell, and Bessey’s wife Bette Jane around a cove near Horse Point starting sharply at 7 a.m. Saturday as they counted loons for the 31st annual Maine Audubon Loon Count.

Three loons didn’t wait for the official counting to start, which takes place only from 7 to 7:30 a.m. to avoid the likelihood of the same loons being counted twice by different counters, before showing themselves just off the dock of the Bessey’s family camp.

They bobbed on the water with one of the adults preening and rising up to flap its wings and exposing its white underside before joining the other two poking their heads under water, then diving after fish.

The three loons swam quickly away but were still within the family’s assigned counting sector of Great Pond when the loon counting got underway at 7 a.m.

“Jack, let me show you how to read the map,” Chip Bessey said as he showed his blond-haired grandson the area that made up their counting sector, one of 22 sectors on Great Pond covered by different volunteer counters. “Here’s the line, from that point to that point right there ahead of us.”

Chip Bessey’s late mother, Susanne Bessey, was one of the original loon counters when the project was launched 31 years ago to assess the status of loons in Maine.

Since the count that focuses on southern Maine started, the estimated loon population in the southern half of Maine has increased steadily from around 1,500 in the early 1980s to, last year, about 3,700.

The count started, according to Susan Gallo, director of the Maine Audubon Loon Count, because little was known about the birds recognized by their haunting calls.

Before the count started, it was thought the loon population was declining. But the count has indicated otherwise, that the population is slowly but steadily growing, though the estimate has dipped several times over the three decades, including a 10 percent drop in 2012, to about 3,000 loons.

Gallo said loons are counted both because they are a highly visible bird intriguing to people and because their health reflects the health of the water bodies where they live.

“No other bird in Maine, in the region, has this following,” Gallo said. “They are easy to find, see and hear with their distinctive calls, which contributes to this mystique they have about them. But they also connect to so many important, core habitat values – clean water, healthy lakes where people are treating the lake correctly. Loons are fish eaters, and they are visual predators, so they have to see the fish to catch them. So a lake has to be clean and clear, and they need peace and quiet, places to nest. If you have loons thriving on a lake in Maine, you know the water quality is good, you know you have a good amount of components that benefit wildlife, that benefit people.”

About 1,000 volunteers help count loons every year. A sampling method is used to determine an average which is then applied as a model statewide. So the number reported every year is an estimate, not an actual count.

The loon count for 2014 wasn’t available Saturday as officials still need to receive the surveys counters are asked to complete. Counters are asked to tally the number of adults and chicks they see.

While the adult population has steadily grown, that same steady growth hasn’t been seen in the chick population, nor has any obvious trend shown itself in the chick population, which has numbers that can go up dramatically one year and down the next. The 2013 count tallied 324 chicks for the southern half of Maine, more than in 2012 but fewer than in 2011.

Gallo said lead poisoning, including from lead fishing sinkers, is the leading cause of death for adult loons in Maine. “And although (lead poisoning is) not a direct cause of death for chicks, chicks who lose a parent to lead poisoning are probably less likely to survive with only one parent left behind to care for them.”

Loons live between 25 and 30 years, and generally don’t start breeding until they are seven years old or older. They average one chick every other year, a fairly low level of reproduction, Gallo noted.

She said other threats to loons include extreme rains that flood nests, predators and disturbance from boaters.

Saturday morning, other than a boater two docks down from the Besseys who the family believed was also heading out to count loons, Great Pond was calm and quiet as Casey and Abigail used two sets of binoculars to see if an adult loon they’d spotted had any chicks with it.

The family spotted no chicks during their count, but did spot a record, for them, of six adult loons in their sector of Great Pond. Jennifer Kidwell said that during some years they don’t see any.

Chip Bessey said often in the early mornings, it’s just him and the loons on the lake. And at night the lake echoes with their haunting calls and, sometimes, loud shrieks which can catch visitors unfamiliar with their calls by surprise.

“The loons, they’re our neighbors,” Bessey said. “The calls of the loons give flavor to being here.”