When new federal rules required fishermen to swap floating rope for sinking rope-to protect endangered right whales-the brightly colored floating line piled up on the dock. But what can you do with a mountain of discarded line?

The answer, clearly, is to make doormats. “It’s taken off. We can’t really keep up. They’re flying out the door,” said David Bird, whose Custom Cordage Company in Waldoboro, Maine is producing colorful Downeast Doormats. He has made thousands of mats in the past few months, churning them out at a rate of about 40 per day. As of April, the company is selling about 1,000 per month.

Smaller ones retail for about $50, bigger mats, $80. Bird hired two idled fishermen to help make mats, which are woven on jigs that feature a row of removable pipes. It’s not exciting work, but it’s given Custom Cordage a boost. Bird has called back two laid-off workers and returned to a 40-hour work week after an earlier cutback caused by sluggish sales.

Bird was turning out mats on a small scale until he teamed up with entrepreneur Penny Johnston of Waldoboro, who handles sales and marketing and came up with “Downeast Doormats” from her Maine Float-Rope Company. The rope is free for carting it away, and as Johnston points out, “At least it’s not ending up in the landfill or entangling whales.” Johnston knows marketing. Previous ventures include selling old fieldstones for landscaping and turning old barn boards into furniture.

Bird knows the ropes. He spent 22 years working for the now-defunct Crowe Rope Company of Warren, and then started his own business 11 years ago.

He takes credit for realizing the potential of floating rope turned in by Maine lobstermen. Johnston takes credit for ramping up sales. She displayed Downeast Doormats last March at the New England Products Show in Portland and won a best in show award.

The doormat business isn’t going to run out of material soon. Millions of pounds of rope have been turned in; Johnston said she just picked up 168,000 pounds in Rockland. She is considering a “buoy” line theme, even a Caribbean theme for the mats.

Johnston wants to help the whales and the fishermen. She said she will donate a percentage of profits to the Gulf of Maine Lobster Foundation. This foundation conducted a rope exchange program in which lobstermen who brought in floating rope were given vouchers to buy sinking rope. As of March, the foundation gave out $1.4 million in vouchers. There are about 300 right whales left in the northern Atlantic.