PORTLAND, Maine (AP) Maine’s annual census of loons found slightly fewer adult birds but more chicks this year.

Maine Audubon conducts a loon count every year. The state has the largest population of the birds on the East Coast and has sought to protect them with environmental laws in recent years.

The adult loon estimate fell from 3,446 to 3,057 this year, Audubon said in a statement on Monday. That was still more than twice as many loons as counters found when the census began in the 1980s. Also, the number of chicks rose from 224 to 298, the group said.

One of the threats to loons is the operation of motorized watercraft, such as boats and jet skis, that do not observe state laws requiring slow speeds near shores and islands, Audubon said. The birds are vulnerable to boat strikes, and their nests can also be washed out by wakes.

The birds are also vulnerable to lead poisoning from the ingestion of fishing tackle. Maine has introduced limitations on the use of such tackle to protect the birds.

Audubon said in a statement that “while the increase in chicks is a welcomed event, threats remain abundant.”