Pink dolphins Amazon, by canoe.

The tour sold here is a full day from Manaus. It lasts 12 hours, starting when you are collected at the hotel in the morning and ending when you are dropped back in the evening. The guides speak English, Spanish and Portuguese, and private or small groups are on offer, which suits families and friends who want the day to themselves.

First the road runs west for a short while, and a motorized canoe carries the group into the forest for a long walk. Lunch is plain, and afterwards comes the dolphin conservation project, where getting into the water is possible. Piranha fishing, a ride toward sunset and a night search for alligators fill the rest of the day.

Seats start from $140, nothing is due when you reserve, and a cancellation at least 24 hours ahead refunds the full fare. Cruise-ship guests can ask for a special start time, and for limited mobility the listing proposes a river day tour instead.

At the dolphin stop you visit a conservation project, learn about the animals and the work done to protect them, and may enter the water. Pack swimwear and a towel. You meet the Amazon river dolphin, pink in the adult male, an animal the Brazilians call the boto.

Colour changes with age and sex: young animals are dark grey, and adult males that are sexually active turn far pinker as scars from fights build up. Adult males can grow to 2.55 m and 200 kg, which makes the animal beside the canoe large and strong.

On the lower Rio Negro the contact now rests on food handed to the dolphins, ICMBio says, and a research project there looks for lighter ways to meet them. Find out how the stop is run, and read the swimming guide on this site before you enter the water.

The listing warns that some activity places may differ between the wetter half of the year, November to June, and the drier half, July to October. The river rises and falls, and with it the channels the canoe can use and the lakes where the dolphins are found.

Rain is lightest in the dry months: July averages 67.1 mm, August 56.1 mm and September 79.0 mm at the INMET station. The Rio Negro itself fell to 13.29 m at Manaus in October 2023, its lowest mark in 121 years of records.

For the boto itself, the calves arrive mostly as the water falls, when fish are packed together, and breeding runs between July and October. What the river is doing that week matters more than the calendar, so ask your guide before you travel.