GREENVILLE, Maine — Witnesses who reported a snowmobiler wearing all black and a black helmet struggling to escape Moosehead Lake’s East Outlet actually may have seen an otter, Maine Warden Service officials said Friday.

Warden diver Bruce Loring and airborne game wardens combed an icy 150-by-200-foot area of water and nearby woods for five hours Friday before ending the second day of the search, said Deborah Turcotte, the Department of Inland Fisheries and Wildlife spokeswoman.

No one can certify that a drowning didn’t occur, but the totality of evidence supporting an otter sighting made the wardens, including warden Cpl. Mike Joy, the dive team commander, advise ending the search.

Confusing an otter for a human “doesn’t happen very often at all, but there is quite a bit of otter sign on the ice,” Joy said Friday.

Thursday’s search began after 2 p.m., when three people onshore reported seeing a person struggling in the lake near Wilsons campground. Wardens used an airboat on the water as warden pilot Charlie Later flew overhead.

Joy based his recommendation on the distance between the witnesses and the supposed drowning area; the sun’s glare off the ice; and the lack of a missing person’s report, snowmobile tracks or of a body, snowmobile or other equipment in the water, he said.

“There were tracks in that area, but a person there said they left those tracks a few days ago,” Joy said.

Wardens found pieces of crayfish and a small bloodstain on the ice near where the person would have gone in, signs that at least one otter was there having a snack, Joy said.

“With the glare from the ice conditions, an otter would look black in color, and witnesses said the [snowmobiler] was wearing all black with a black helmet,” Joy said.

Otters were in the area, Joy said.

Friday’s search ran from 8 a.m. to 1 p.m., Turcotte said.

“Conditions were perfect. It was very well-lit underwater,” she said.

Greenville police and firefighters preceded the wardens’ search with an hour-long search of their own Thursday that began about 30 minutes before the first wardens dispatched arrived, Greenville firefighters said.

Firefighters Gavin Oeschlegal, Andy Hunt and John Simko used cold-water suits and a rope system to get through the shelf ice. They found nothing. Nor were there any apparent ice breaks big enough for a sled or person, Simko said.

Greenville police and a C.A. Dean ambulance stood by on shore.

The East Outlet region has been a problem area for snowmobilers for years. The most recent accident involved a Pennsylvania couple who went through the ice in 2009 and whose bodies later were recovered. Several rescues have occurred there.

A fatality on Damariscotta Lake and a missing snowmobiler on China Lake have been reported this winter, Turcotte said. Snowmobiles and a couple of trucks have gone through the ice, she said.

BDN writer Diana Bowley contributed to this report.