The tiny night monkey is with Martha Silva 24 hours a day, nestled in a wool pouch inside her coat or beside her while she sleeps. Eight times a day, she pulls out a milk syringe and nurses the five-inch baby like an attentive mother.

The long hours of monkey mothering don't bother the 54-year Colombian woman, she said, because she already raised two children.

"To me there is no difference. You have to look after each the same. When you give them the bottle, you have to make sure they don't choke. When I'm working, I make sure he doesn't get out of the little bag I have. If there is sun, I take him out of the sun," said Silva, who works with the neonatal unit of Bogota's Wildlife Reception Center, part of the capital's environment ministry

Silva, who has children of 20 and 30, began working at the center west of Colombia's capital in 2000. There she has nurtured species ranging from birds to turtles to primates.

Now she is looking after night monkey of the genus Aotus that lives in the tropical forests of South America, including Colombia, Brazil and Ecuador. The monkeys got their common name because of their unusual nocturnal habits.

"I carry them with me for a couple of months, in general, or the time that is required," she told The Associated Press. Her husband and daughter help her with the household chores and cooking while she is occupied with a baby animal.

She never gives her animal charges names so they don't become seen as pets. In the long term, the center aims to return them to the wild.

Her latest baby, a male night monkey with dark fur, beige brows and large, protruding brown eyes for night vision, arrived at the center on Feb. 4, weighing a scant 100 grams, or about one-quarter of a pound. It was brought by a man who said he found it abandoned on the side of a highway in Colombia's eastern plains near Meta province, said Judith Cardenas, the center's chief biologist.

When the monkey arrived it was about 5 days old and the man said he couldn't bring himself to leave it to die, Cardenas said.

Biologists at the Bogota center don't how this baby ended up being orphaned, but they say the mother may have been killed or lost the baby. Cardenas said Amazon-region monkeys are often hunted for meat, for experiments or as pets.

Silva, a pony-tailed woman with nails painted emerald green, made a small bag of brown and black squares to hold the monkey, which is still too young to walk. They sleep together and Silva takes the monkey to the center each day on her bicycle, the baby snug in the wool bag. Every three hours, the monkey must be fed delactosed milk with vitamins added, using a syringe, said Cardenas. In the wild, adult night monkeys eat leaves, insects and small lizards and frogs.

When he grows up, the monkey will weigh 800 or 900 grams (1.75 to 2 pounds) and stand about 34 centimeters (13.4 inches), Cardenas said, adding that he will look like "a medium-sized teddy bear."

She said that this type of primate passes the first three or four months of its life clinging to or hanging from the back of a parent as it swings through the trees. Orphaned, they need a substitute mother, like Silva with her wool bag kept close to her body. This idea of using substitute mothers for orphaned baby monkeys has been used in other parts of the world and in Colombia in recent years.

The plan, according to Cardenas, is to let the baby monkey grow and then place him in a large cage in the center, next to another monkey of the same species. If they accept being in the same cage together, the center and environmentalists will begin a process of trying to introduce them into the Amazon jungle with a monkey group.

"This kind of primate lives in family groups, with a father, mother and children ... They are a bit like us," said veterinarian Claudia Brieva, who coordinates the center's rescue and rehabilitation unit. She said that means you can't just release an orphaned monkey alone into the jungle. A baby can be accepted by another family, however, or create its own, she said.

The International Union for Conservation of Nature lists a dozen species of night monkey on its Red List of threatened species. Though none is listed as endangered, several are suffering declining populations

In Colombia, Brieva said, "Their natural habitats are being destroyed by the expansion of the agricultural frontier, by the indiscriminate cutting o the forests and jungle."

Silva says she has raised two other baby monkeys and both of those were freed in different parts of the country. She hasn't heard anything about them since.

"It is like with a child. You are at peace because they are going to be in their natural habitat," she said.