FREEPORT, Maine (NEWS CENTER) -- Clam diggers in many of southern Maine's coastal communities say rising home prices in towns where they harvest is slowly gentrifying the communities.

“It’s becoming more and more difficult to live here and access the shoreline," said Chad Coffin, a career clammer and president of the Maine Clammers Association.

Coffin has spent his entire life in Freeport, which he said helped him get established in his business there.

“It’s becoming almost impossible for working class people to establish themselves. The cost is too high," said Coffin.

The problem, he said, originates with a clam licenses. Towns have only a limited number of clamming licenses to issue, and 90 percent must go to town residents.

“Once you lose it, the chances that you’re going to get another one are very slim," said Coffin. "It doesn’t have the same benefits that it used to.”

As home prices rise, diggers with lower incomes can not afford houses in the areas where they clam.

The Greater Portland Board of Realtors reports that Yarmouth home prices increased 25 percent between 2011 and 2016. Freeport home prices increased 20 percent in the same time period.

In 2011, the median price for a home sold in Freeport was $284,000. In 2016, it was $339,950, according to data from Maine Listings. In Yarmouth, the median home sold for $329,000 in 2011, and for $414,750 in 2016. Of the 39 active listings in Yarmouth in 2017, the median list price is $779,000.

”I think that’s a sharp increase but I think that’s because the past year or so we’ve seen such an incline in prices and decline in inventory so it kind of makes for a perfect storm," said Raylene Estabrook, president of the board. "Those who are looking for more affordable houses tend to be driven out with the prices in the market."

She and Coffin both said that lower-income earners are being forced to find homes farther away from the coasts, where property values have increased.

Coffin worries that clammers may eventually get pushed out of some towns completely.

“Overall, the trend is for continued decline. Certainly in southern Maine, there’s some communities where commercial clamming is part of it’s history," said Coffin. "It's not a current industry. It's a past industry."