A whale that swam some 1,600km up the Amazon could get a ship ride back to the ocean, environmentalists said on Monday.
The 5.5m minke whale was stranded on sandbars at least twice since first spotted in the Tapajos River, a tributary of the Amazon, on Wednesday.
A group of biologists and veterinarians managed to examine the animal on Sunday along the river near Santarem in the rain forest.
The group was trying to contain the whale in a small area of river while it tries to arrange for a ship to carry it back to the sea, said Milton Marcondes, a veterinarian with the Brazilian Humpback Whale Institute, which is taking part in the efforts to save the whale.
"It is in good condition," he said. "We couldn't do a blood exam, so we don't know how it is doing internally, but we gave it antibiotics as a precaution."
Marcondes said the whale, a male, has a superficial injury and small bruises on its skin, but none of the wounds are serious.
Rescuers, including local residents, trapped the whale on Sunday, but had to let it go before a net was secured around the animal because it became agitated and was at risk of injuring itself.
"We can't forget this animal has been away from its natural habitat for a long time," Marcondes said by telephone from Santarem. "It is stressed and can easily get sick."
The whale has been in the river for at least 15 days, he said, adding that there have been cases of whales surviving more than two months away from the ocean.
He said feeding is not a problem because whales can go about six months without food.
The whale was not likely to find its way back to the ocean by itself because the river has "too many tributaries that could confuse" the animal, Marcondes said.
The whale ran aground for the first time on Wednesday and was briefly grounded again a few kilometers away on Saturday.