Kids Saving the Rainforest

Are rescued Squirrel Monkeys suitable for release to the wild?

By M.Sc. Daniela Solano-Rojas, President, Fundación Saimiri
[email protected] 

Bonnie & Clyde
Bonnie & Clyde
In 1999 when I started my career at the University of Costa Rica, I never imagined that an organization started by 2 kids willing to save the rainforest in tropical Costa Rica would be such an important inspiration to my future work. 

Kids Saving the Rainforest started as a dream of Janine Licare and Aislin Livingston when they were only 9 years old, back in 1999. They both saw the rainforest disappearing and the negative impact of this on the animals, particularly the Squirrel monkeys. After 13 years, the KSTR role in the conservation of Central Pacific Squirrel Monkeys has been astonishing. Rescued animals and monkey bridges are some of the highlights. 

Kids Saving the Rainforest Logo

Talking about rescuing monkeys is not easy. Working with non human primates in captivity is a very hard work and any person willing to do so has to have a combination of passionate work with a mix of responsibility and a lot of commitment. And when we mean commitment it almost means your family will be the monkeys, sloths, birds, anteaters and other wildlife that on a daily basis are injured and need to be received in a Rescue Center. 

Taking care of all these cute animals might sound romantic but for doing so you must make personal sacrifices and do it with the reward to see animals that are injured recover and being able to go back to a normal life in the wild. What an inspiration is the team working in the KSTR Rescue Center. They do this and more everyday. 

All they give to these animals in need will somehow be rewarded as well by a memorable experience you can also enjoy when doing a fascinating tour in KSTR facilities. Seeing squirrel monkeys, porcupines, kinkajous plus 70 other wildlife, including 5 species of monkeys, on the tour is quite an experience.

Taking care of primates is not new. In fact, such a hard work has been done historically  by many people but especially women. It is for the remarkable scientific work done by Dian Fossey, Biruté Galdikas and Jane Goodall that in the 70´s Westerner learn about the Great Apes and its threats, as well as their sociable and smart nature. 

Jane Goodall found out that chimpanzees use tools, redefining the concept of man, as the use of tools where before that discovery, was a capacity attributed to humans only. 

But why is there still so many endangered monkeys species in the world, why is there still so many threats for these cute and intelligent animals? 

I learn, with sadness, that still many people were not caring not only for the Great Apes and primate species around the world, but for our monkeys inhabiting Costa Rica. They are threatened by illegal logging, deforestation, industrial cash-crops, highways, electrical wires, among others. 

It was with this panorama and with the willingness to help the vulnerable Squirrel Monkeys and the other 3 kind of monkeys of Costa Rica, that I founded my own NGO in early 2010. I was also choosing, like those 2 little girls back in 1999, to take action. Saimiri Foundation is a small organization working with monkeys in the wild and trying to secure their last remnant of suitable habitat. 

So,  I ventured to volunteer for a week in the KSTR Rescue Center, with the aim to provide preliminary guidelines to release a troop of 8 monkeys that have arrived at the Rescue Center for different reasons but mainly from pet trade and orphanage (product of run overs on the highways). 

So here are some preliminary general guidelines I produced while visiting my friends, the monkeys, in the Rescue Center: 

1. How big should a troop of Squirrel Monkeys on a Rescue Center should have to be release? 

It is important the group should at least have 15 members with different age and sex. 

In the field, troops have an average of 20 individuals per group. Groups of 7 and 9 have been reported but this is the lower limit for a troop size, so if you should release a group this size, you should secure high habitat quality as well as assessing the threats in this habitat will be a fundamental part of the work one should do prior to the troop release. 

2. How should the habitat in which we release the monkeys be? 

Squirrel Monkeys prefer secondary growth forest, this mean the forest that has grown after a natural disaster or as a result of a pasture, led to regrowth again. In many cases this kind of habitat is outside formal protected areas and its future depends on its owner, making habitat for the Squirrel Monkey vulnerable as well. 

3. How far from other troops should the Squirrel Monkey be released? 

In the wild, Squirrel Monkeys can overlap their territories.  When my advisor Grace Wong did her fieldwork with the Squirrel Monkeys back in the 90’s, she found that some troops might overlap even 50% of their territories. This can happen as they were sharing a National Park Forest, big enough for all the troops at the moment. But as habitat started to shrink from overdevelopment and human activities and the troops growth each year, the remaining habitat is not enough. 

We should release a rehabilitated troop in the territories of other squirrel monkeys troops only if the forest is more than 30 ha and it is connected through corridors to other patches of suitable habitat. The more fragmented the forest or habitat is, the less overlap in their territories should be. 

Measurement of Success of a release troop 

Number of individuals per year in the release troop

When releasing your troop you know the age composition and sexes. In the wild is very difficult to establish their sexes just by looking at their genitals. You should be familiar with the behaviour of males, females and juveniles, as well as, the troop member who might have a mark or a special feature you can recognize. Keep a record of the number of individuals by counting the troop number of individuals at least twice a year. If your group gets lower than 7 individuals s not suitable for long term success. 

Number of food item consumed

In nature, Squirrel Monkey troops prefers insects in the dry season. They also eat fruits and nectar from flowers as Passifloras. In the Rescue Centers normally they will eat food that might be not available in nature. So it will be also important to documenta at least 4 times a year the list of food items eaten by the troop. 

Home range

The Squirrel Monkeys home range when Grace Wong studied them varied from 35 to 65 ha. It is important to document the home range of your release troop at least 4 times a year. As the insect availability (main food item in dry season) changes availability their home range will also change. You need to measure its home range twice in dry season and twice in rainy season every year. Remember they come from an enclosure! 

Monkeys are the gardeners of the forest, they pollinate some flowers, they disperse seeds and they eat insects, as a result they give benefits as preservation of biodiversity, habitat restoration and pest controllers, respectively. 

Other activities that should be done while releasing Squirrel Monkeys are Environmental Education. The majority of monkeys arrivals at a Rescue Center are due to the negative impact of humans. We need to help other people understand the importance of our actions. 

Environmental education, together with sound legislation, sustainable management, ecotourism, responsible businesses will ensure the protection of the Squirrel monkeys, so future generations will have the joy to see these little cute monkeys jumping and running graciously in the tree branches of the tropical rainforest on Central Pacific Costa Rica.

How to support Squirrel Monkeys from the Rescue Center to be back in the wild? 

Join a tour in KSTR facilities. The tours are offered 4 days a week (Mon, Wed, Fri, Sun) from 9 – 11 AM.  Contact Vernita at [email protected] or Hotel Mono Azul at 2777-1548 or 2777-2572 

Recommended books: 

1. Mamíferos de Costa Rica. 1999. Eduardo Carrillo, Grace Wong y Joel Sáenz. Editorial INBIO.

2. The Mammals of Costa Rica: A Natural History and Field Guide. 2007. Mark D. Wainwright. Zona Tropical Publication.