A group of 66 tame chimpanzees used for US medical testing faces being abandoned on six Liberian islands amid a potential funding crisis.
The animals are those left from 108 chimps used for biomedical research carried out by a New York-based charity, Blood Center.
I took a boat ride to accompany a team of people taking food for the chimps.
The animals knew when food should arrive and started to mill around the distribution point just before we got there.
Samantha, in her mid 40s, is the oldest.
She and two others, Mabel and Bullet, stood before a group of animals which gathered as the feeding boat arrived.
Other notable names on the islands include Joyce, Stewart, Duno, Hellen, Ellie, Annie and Teta.
They were very excited - shouting and making joyful noises as they jumped and swaggered up and down.
As the boat zoomed in, an outburst of giggling and shouting echoed across the island, with chimps rushing out from the bush, climbing trees and joyfully descending to grab something to eat.
They are given food once a day, scrambling over pumpkins, plantains, pawpaw, rice, sugar cane and pears that are brought over on the speed boat.
"We don't give any of them food until all of them have gathered so that they are served together," said Joseph Thomas, a caretaker who has looked after the animals for 36 years.
Mr Thomas called each chimp by name to come forward for food.
As he threw coconut and cucumber to the chimps, he stroked their noses.
Mr Thomas introduced me to Bullet, a middle-aged male.
He was named by conservationists who rescued him and brought him to the island.
As an infant in the 1980s, Bullet lost his right hand to a hunter who shot and killed his mother.
As part of an effort to keep the animals alive in all weather, there is a reservoir on each of the six islands that the chimps have learned to use to fetch clean water when the dry season sets in and the river becomes dried out and salty due to infiltration from the Atlantic.
"They know where to press for fresh water to shoot out to drink," Mr Thomas said. "Every one of them can operate it."
Chimpanzees don't swim
He says the animals now feel closer to human beings than their compatriots in the wild.
Some were born here and some have spent 25 years in captivity.
Mr Thomas fears that if the chimps are put back into the wild they will go to wherever they hear the sound of humans.
This, he said, makes it difficult to take them back to the jungle to live.
So, he said, they are kept on islands "because chimpanzees don't swim".
On another island, where nine reside, the chimps came out of the bush, each washing their hands hurriedly as the food boat arrived.
Rice was served first, followed by cucumbers, pumpkins and pears.
Boat operator and caretaker Julius Cooper took a pear intended for a chimp who had not received any.
The fruit had been intercepted by another chimp. Mr Cooper told the chimp to return the food and he did so immediately, even if he yelled and jumped in anger.
If the chimps aren't fed every day they will start eating leaves.
John Abayomi Zeonyuway, administrator of the Liberia Chimpanzees Rescue Project, says this leads to constipation because the leaves are hard to digest.
Eventually, he says, if they carry on eating leaves, they will die.
But it is expensive to feed them - about $25,000 (£16,000) a month.
That's a bill Mr Zeonyuway says that the Liberian government has not shown it is prepared to pay.
The Blood Center announced they were going to stop supporting the islands in March after 40 years involvement with the chimps.
In 1975 the blood bank and research facility signed a contract with the government-sponsored Liberian Biomedical Research Center to do medical tests on the chimpanzees, including studies which led to the development of a Hepatitis B vaccine.
After the chimps had been tested in the lab just outside the capital, Monrovia, they were released on the islands.
But the Blood Center says its research ended in 2007 and since then, it has been supporting the sanctuary on a voluntary basis until the Liberian government was able to take over.
After the research institution pulled out, another group, Washington-based Humane Society, stepped in to pay on a temporary basis.
The islands are now under the custody of the Liberia Institute for Biomedical Research - an animal and medical research centre that is itself struggling due to lack of funding.
But fishermen inadvertently cause the chimps distress.
When they go fishing near the island, the animals think food is coming their way.
People in the region have come to appreciate the difficulties the animals are going through.
"The feeding of these animals should be everybody's business," appealed Christine Garr, a resident of nearby Marshall Town.
As she boarded a dugout canoe, she said: "The animals are our friends even though a chimpanzee is nothing to play with".