Welcome to my home page all about marmosets, those wonderful little creatures who become part of your family for many, many years. My name is Paul and I live in Johannesburg, South Africa, I am a keeper of Marmosets.
Marmosets are distributed mainly from the Amazon Basin, south of the Amazon River in Brazil, east to the Brazilian Atlantic coast and extending over into Eastern Bolivia.
Callitrichids' natural diet consists of fruit and flowers, as well as frogs, snails, and lizards. They also feast on a variety of insects. Plant exudates and gums are also consummed, the marmost has dentition adapted for gouging holes in plants in order to get to the gum. The digits have curved claws, except on the big toe which has a flat nail. The curved claw adaption assists in horizontal jumping by enabling them to run up the sheer side of a tree. It also assists in grooming. Their body length is 225 - 309mm, the tail is 279 - 406mm and they weigh between 255 and 454 grams.
Marmosets live in pairs or family groups in which only the dominant pair breeds. The fathers participate in the rearing of the offspring and help by carrying the youngsters about and returning them to their mother for feeding. This way the mother can have a break. Territory is marked by rubbing glands located either on their chest or anogenital region against an object.
Marmosets have a V-shaped mandible with incicors that are extended and nearly level with the canines, resulting in a cup or scoop-like shape, these teeth are extremely sharp and can cause quite a bit of damage if one is bitten. This feature enables the marmoset to gnaw holes in order to gain access to tree exudates.
For those contemplating breeding marmosets, you should be aware that occasionally female parents have been known to be "tail biters" in that they will actually bite off the tail tips of their offspring. Only if severe bleeding results or some other form of abuse, neglect or health problems occur, should an infant be removed for handrearing. Handrearing is also a consideration when a pair produces triplets or quadruplets. One suggestion is that the extra infant be removed and hand fed for 24 hours, then put it back with the mother and remove another of the infants. Rotating infants is better than just choosing one for handrearing in that they will all receive care and a normal social upbringing. Of course, the effectiveness of this method will depend on the behaviour of the parents towards your interference, and on whether you have the time it takes to care for such a tiny infant. Another important consideration in regards handrearing is that handreared marmosets often become extremely aggressive towards humans later in life. In situations where an infant has been orphaned or rejected, it may be possible to foster it onto another female which has either recenlty lost an infant or may have only one. To increase the odds of acceptence, the foster infant should be rubbed over the foster mother's body, paying special attention to her scent glands. In addition, placing the baby in the foster mother's nest box, possibly with her own infant if available for an hour can increase the chance of acceptence.
Vitamin D3: Vitamin D3 is extremely important to New World primates in allowing them to properly utilize calcium. Vitamin D3 can be given orally through a commercial diet, however the best source is through natural, unfiltered sunlight (Ultra Violet rays). Unfortunately many marmosets cannot have access to this sunlight all year round, in such cases, a vitamin supplement should be added to their diet to ensure that the monkey is receiving adequate amounts of D3. Metabolic bone disease such as rickets, is the result of a D3 deficiency. In extreme cases, the major organs can also be affected.
I will now go on to give more detailed notes of the various topics discussed above, we will discuss housing, feeding, toys, etc.
Although some people will aquire an adult monkey, most will start with a young infant or individual which usually starts out its life as a member of the human family. As non-human primates mature, they usually become strong willed, dangerous and unpredictable, so when designing a cage to hold a monkey, every possible outcome of personality should be considered to safely and humanely house the monkey throughout its entire 20 to 40 years of life. The design should allow for feeding, watering and cleaning to be accomplished from either the outside of the cage or while the monkey is locked into a sectioned off area of the cage. Design your cage so that if you fall ill or are away, a non-household person can safely and efficiently maintain the monkey. It is always a possibility that your monkey may bite someone. If this happens, you must be able to keep the monkey secure in its own cage rather than let it go to a quarantine facility, where it could become stressed out and eventually die.
Seeing an active, intelligent primate kept in a small, sterile environment would horrify the average primate enthusiast. The minimum requirement for an enclosure would be so that the monkey can turn around freely and lie stretched out without being encumbered by the cage perimeters. Such a standard permits a marmoset to be confined in slightly less than a 2 foot cubicle, although it is hoped that individuals keeping primates for personal enjoyment would provide for the pleasure and psychological wellbeing of the monkey with more elaborate housing.
For Callitrichids, a cage of 1 by .5 by 1.25 metres with two perching branches in "adequate" for an adult pair. Light weight welded wire of 25.4 by 25.4 mm is adequate to hold marmosets. Anything bigger should be avoided as the young can escape through it. Cage size should be increased by 25% of floor area for each additional animal. The top of the cage should be at least 1.75 m high, as these little monkeys feel more secure if they can get up higher than gazing human eyes, do keep in mind that these measurements for the cage are the MINIMUM sizes that should be used.The cage where I have my pair in is 2 metres by 2 metres by 2.8 metre in height. This has given me ample room to put all sorts of ledges and branches in it at varying heights, with ropes and trees planted inside. The floor is covered in straw with lots of plants planted in it, we will discuss the various types of plants that can and cannot be used for marmosets later.
Although the importance of access to outdoors is not fully understood by scientists, there is no doubt that it has very serious implications both on the phisiology and psychological wellbeing of primates. Cages will, of course, have to be modified to protect occupants from the elements of nature in the climate in which the owner lives. In Johannesburg I have an electric blanket in the sleeping box in the winter, and I turn it on when it gets cold. Outdoor cages should include a solid roof over a portion of the cage to protect the monkey from rain and sun, and a heated shelter or nestbox to escape chilling winds and cold. Likewise, totally indoor cages indeally should incorporate a north facing window for fresh air, sun bathing and viewing the great outdoors. In the absence of natural, unfiltered sunlight, a good source of vitamin D3 will be necessary for the proper absorbtion of calcium.
The first step to planning a cage for your marmoset is to draw up a floor plan. The desired location in the house, garden or both should be incorporated into the plan as well as consideration of environmental factors, such as sun, prevailing wind, direction of rain etc. Generally the northern sun should be kept open for sunning and the southern sun for shade, east and west sun can also be used for sun bathing. Draw out a rough sketch of the area to be used, and then draw in a safety entrance and areas for the monkey's shelves and sleeping areas, keeping in mind full utilization of the winter sun whilst also protecting from the elements such as a hot summer sun, rain and wind. Floor plans should be suitable for your specific situation and climate. In cold areas, more attention should be given to indoor facilities, whereas in warm areas an insulated sleeping box placed in an outdoor facility should be adequate. The choice of floor type will also depend on the area in which you live. If the soil is well drained and dry, the risk of bacterial infection will be low, and a dirt floor will be adequate. In such a circumstance, some caretakers will choose sand which can be easily repalced when it needs cleaning, or, if monkeys will allow a covering of grass which can also be raked to be kept clean. Simple red landscaping bricks or pavers should be adequate for marmosets. Care should be taken to anchor the cage into the ground very well so that a strong wind cannot upend it, allowing the monkeys to escape. Areas where soils (clay) are known to harbour bacteria, parasites, and other diseases, require a cement slab floor or wire bottom suspended above the ground to prevent the monkey from reaching food and other contaminated items which have fallen onto the soil. Cement slabs offer easy cleaning and sterilizing and would be the material of choice if finances allow. My cage is tiled with pavers and on top of that I have straw in case a monkey accidentally falls, it will soften the fall, and also for mothers and babies when the baby looses his grip on an older monkey he will fall onto the straw mat and not onto hard concrete. The cement slab should be smooth and properly sloped to allow for hosing down without leaving puddles behind, in which bacteria will have a field day. Ideally, a cage can be hosed clean from the outside while the monkeys are locked in another section or are in the upper portion of the cage where they will not get wet. Floor choice in an indoor cage takes alot of thought as it will have to withstand a lot of abuse. A sliding metal tray works OK for a smaller indoor cage. Remember that not all the waste and debris will fall in the boundries of the tray, so the tray should extend at least 30cm outside the perimeter of the cage. A large piece of linoleum can also be used as it can be mopped and swept easily. Larger indoor cages will require formica or any other floor type used in kitchens and bathrooms, tiles work wonders. When using a drop tray, wood shavings, shredded paper, straw or other coverings can be used below the cage to absorb moisture and make cleaning easier, remember that if you monkey can reach these coverings, it becomes a game for him to throw them all over the place. Mine used to rip up the newspaper into tiny pieces and throw it all over the place causing a huge mess in my house. Care should be given to design the indoor section so that it can be cleaned while the monkey is on the outside section or contained above or beside the area being cleaned. Keep in mind that your sweet natured baby may not always be manageable during cleaning and may become quite possessive of "their territory", or of course he may try to make a great escape. Two section cages become a necessity rather than a luxury.
Now that the floor plan has been drawn in detail, you are ready to plan the actual cage structure. As a rule, it is best not to use wood for integral structural components as some monkeys become habitual chewers and so destroy the supporting studs. If you are going to use wood in the construction of the walls, attach wire to the inside of the wood frame to minimize damage by chewers. Pressure treated wood is often used for cage framework, however, it is vital that the monkey NOT be able to chew the wood as it is TOXIC. Solid walls are the best, either lined with sheet metal or with wire, securely fastened with ample screws along all the edges. Dry-wall, particle board, and other soft building materials can be quickly destroyed by a motivated monkey. NEVER underestimate the strength of these little monkeys, remember, monkeys' muscles are 4 to 10 time stronger kilogram for kilogram than human muscles. What better activity is there other than for a monkey to systematically tear their cage apart piece by piece. Some monkeys are pickers who will pick their cage apart piece by piece, others are smart enough to dismantle it and yet others will use pure brute force to rip it apart. This is why proper planning and construction of the cage is important. Care should be taken to choose materials that are safe for the monkey. If you have glass windows, these are best replaced with perspex. Fibreglass roofing or insulation must be out of reach due to the health risk if the product were ingested. In cold climates, metal and plastic sleeping boxes and shelving can lead to frostbite of the fingers and toes and the tail in below freezing temperatures, unless these exposed areas are covered securely with carpet or wood. PVC piping (for perches, swings etc.) reduces conduction of heat from the hands and feet to the surface. Natural branches and logs used in the cage must be of a non-toxic plant species (we will be comimg to this). Electrical chords supplying power to heaters must be housed in METAL conduit and securley fastened, and outlets should not be accessible to curious little fingers. Exposed nails, wire and metal should be sanded or filed down to eliminate sharp edges. Remember that a monkey confined to a cage will explore and come to know every square centimeter of its home. More area means more for the monkey to do, and a large enclosure will endure less stress and strain than a smaller one. The enclosure should be functional, efficient, durable, secure and aesthetically pleasing as it may require two or three decades of use from your healthy young monkey.
The two compartment cage system requires some type of shift door or monkey door through which the inhabitants can access the different sections of the cage. There are a few types of shift doors, the most important feature of which is that they can be operated and locked from outside the cage. Most "doggie doors" are generally good between compartments, or, if you are handy, one can be made out of perspex or metal for the sliding door, and grooved hardwood or metal to hold the frame of the door. A guillotine style door is another option, as monkeys will learn to lift the door to open it, and gravity will ensure that it remains closed at all times. Whatever type of shift door you choose to make, make sure it is monkey proof so that it will truely serve as a security door.
Now that attention has been given to the safety and security of the interior of the enclosure, lets take a look at the sefety of the perimeter, as no monkey cage is complete without giving some thought to the safety of humans and other pets. Perimiter fences are a good idea to keep children and other pets away from the cage, this will stop uninformed people from getting scratched or bitten. You may want to cover the lower meter of the cage with small gauge wire if the monkey is hostile to other pets or to children. A row of non-poisonous bushes will provide an aesthetically pleasing spatial separation. Monkeys should be regarded as "personal" animals as most are very family or troop oriented. It is not part of their nature to be friendly to or tolerant of strangers. The instinct to frighten or chase away intruders, your invited guests, could result in bites, scratches, hair loss, damage to clothing and a possible law suit. A simple safety fence will prevent most adults from getting themselves into trouble with your monkeys. No cage door should be open directly to the outside as this provides an excellent opportunity for escape. A safety door or double door entry system can be incorporated into most enclosures. I have a double door on mine. This way you can enter the outer "cage" and secure the door before entering the main enclosure. Perimeter fences and safety entrances are all for nothing if cage doors and/or gates are not kept securely fastened, self closing doors are ideal, although I do not have these as I am afraid the monkey gets caught in it as it is closing. Clips and levers may be convenient for you, but they are also easy for strangers to open, and they can be opened by the monkeys themselves. ALWAYS use padlocks on both outdoor and indoor cages and be obsessive about checking and re-checking them prior to leaving the area. A most important factor of good primate caretaking is SANITATION. Keeping monkey environments as sanitary as possible is mandatory to avoid the growth of harmful bacteria and disease. Cages shoud be swept or hosed down daily, especially during the summer months, to remove debris and dropped food. It may be necessary to apply a good detergent and scrub all surfaces, being careful to rinse them thoroughly before letting the animals back in. Once every week or two (at least) the cage should be scrubbed down with detergent and rinsed very well before applying a disinfectant, 1 cup of bleach to 4 litres of water is good, or you can use one of the disinfectants on the market such as "LYSOL". Be sure to use these products in acoordance with what the label says. Generally disinfectants are brushed, poured, or wiped onto non-porous surfaces, allowed to stand for 10 to 15 minutes and then rinsed off well, this is done so as to get the full benefit of the disinfectant. AS IN THE CASE OF USING A DETERGENT, COMPLETELY RINSE ALL SURFACES BEFORE ALLOWING THE MONKEY TO HAVE CONTACT WITH THE AREA. When cleaning the inside of the enclosure, be sure to clean the outside too, this will stop the attraction of pests and ultimately diseases. It is a good idea to have some sort of a ground work outside the enclosure that is easy to be swept clean, such as sand. It is a very good idea to plant on the outside of the enclosure as this adds to the aesthetics and it is a good enrichment tool where the monkeys can pluck the leaves and branches from the plants outside, once the plants have grown big enough, in the meantime, cuttings can be given to the monkeys. It is extremely important to know which plants are toxic and which plants are non-toxic for the monkeys, a list (by no means complete) follows of both categories of plants.
Monkeys are notorious for destroying and killing plant life both within and out of their enclosures. Here are some tips on how to give new plants a fighting chance:
DO NOT USE HERBICIDES OR PESTICIDES/INSECTICIDES ON PLANTS TO BE USED FOR PRIMATES!
List of toxic plants:
As I mentioned before, this is by no means a complete list and you should suplement it with extra reading, if you find any plants that I have not included on either list, you can e-mail me and I will add that plant for the benefit of everyone. My e-mail addresss is paul.millenaar@vodamail.co.za
A most important fact to remember is to supply your non human primate with fresh water ata ll times, this can be done by running a water line to the cage and installing a LIXIT valve.(LIXIT is a registered trademark) valve. There are similar products to the lixit available in South Africa. This device allows water to flow whan a lever on the end is moved or licked in any direction, it is very similar to the water receptacles available for rabbits and hampsters. The problem with this device is that it tends to drip and form a puddle underneath, therefore good drainage is necessary directly underneath the device. Monkeys enjoy just running the water and will force inanimate objects between the valve and casing causing a constant flow. Be sure to install a stop valve out of reach of the monkey so that you can turn the water supply off for servicing.
If you feed dry chow to your monkeys, you may wish to provide potted water in which your monkey can soak the biscuitsand wash other food. A wire basket can be made to house a tight fitting bowl to prevent spillage. This wire housing should have an access hole cut into the top so that the monkey can ghet a drink from the bowl. The bowl should fit tight enough to prevent it from being tipped over. The wire basket is attached to an outer cage wall and a hole cut in the side allows the bowl to be removed and cleaned from the outside of the cage. A similar unit can be installed for food. All water and food bowls and bottles should be thouroughly cleaned and disinfected. * I use stainless steel for all my bowls as it is easy to keep clean and disinfected. Any water whether standing or in water botles should be changed at least every 24 hours. Dry primate diets can usually be fed out of a bucket or plastic flower pots wired or chained to the outside of the cage. The monkey's can reach through the wire to get to the food. Give each monkey its own feeding station to prevent fighting over food and access by only one dominant individual. The food containers should also have holes in the botom to prevent rain water or urine from collecting in them, and to allow for rinsing and washing to help maintain a clean environment.
Sleeping or night boxes can be provided with heat by using thermostatically controlled infrared lamps, which can be set to come on at a desired temperature of 10 to 17 degrees C. One 250 watt lamp can provide sufficient heat for a box which is three to four feet square. It is extremely important that all components of the thermostat and heat lamp, including the power source, be securely protected from the monkeys. The lamps should have a wire screen formed around it to keep monkeys from being burned, and window screening wire to obscure looking directly at the light source. A;lso, the light should be positiooned in such a way that monkeys can move away without actually leaving the box should it become too warm. Bulbless heaters are ideal and safer when compared to the basic heat lamp as there are no bulbs to explode or present a fire hazard. * I use heat blanks in my box, where half the box has the heat underneath and the other half has no heat so the monkey can choose where he/she wants to sit or sleep. Small utility or radiant heaters are another useful alternative in providing heat in larger boxes or small shelters. Again, they must be kept well out of the monkeys reach. Be sure to buy a model that is "spark free", and check often for bits of debris in front of and around the heater. Another alternative for providing heat in the night box is by using heated pads (what I use) within the box. These fibreglass reinforced resin pads provide a uniformly warm surface and can be either bolted to the floor or wall of an insulated box. Together with a blanket, this can provide constant and consistant warmth. As with other heat sources, allow space for the monkeys to move away from the heater should they become too warm, and turn the heat source on only at night and during the most inclement weather. Heat can be contained within a night box by using a swinging pet door, or by simply mounting a trucks rubber mud flap above the entranceway. The construction of the night box should be such that if the monkeys are resting they do not get any drafts. Smoke detectors should be mounted out of reach within the night box using a heat source. Even if the sound may not be hear by you, it can frighten the monkey out of it's night box thereby saving it from smoke inhalation or fire.
What is psychological well being?
Of all the recent efforts to improve the lives of captive primates, the question of psychological wellbeing has taken the forefront. This subject has become a matter of great debate as there is no definitive answer for either primates or humans. The argument also takes on an ethical approach, for some will argue that is a monkey is not aware of what it is missing, or how it is being deprived, then it remains "blissfully ignorant". Does it then suffer? Or does the suffering come from awareness of one's existence? One must consider that if the lack of psychological wellbeing causes a monkey to adapt in negative ways to its environment, then it is indeed suffering, whether it contemplates it or not! Since monkeys cannot be asked if they are content or depressed, it is left up to the caretaker to read their behaviuor and health indicators to determine the degree of psychological wellbeing in their animals. Just as the animals they judge are individuals who adapt in their own unique way to captivity, the caretaker himself/herself is also an individual. Therefore he/she will impart much of their own values into their conclusion. For example, one caregiver may feel that a monkey can be quite psychologically healthy living with a human family in which it perceives itself to be human rather than monkey. On the other hand, another person may feel that a human imprinted monkey that is socially isolated is quite abnormal, and cannot possess true psychological wllbeing when its natural behaviour has been so distorted. The question has no black and white answer. There are two important points to begin from: first, the sffects of captivity on primates are very complex, and many are so subtle that it would take a great deal of behavioural study to identify all of them. Secondly, each animal is an individual and will adapt to its captive environment in its own unique fashion. There are, however, common behavioural responses and repetoires that can be seen, even across species. Caretakers have quite a responsibility. Not only to learn what negative, abnormal behaviour is, but how it starts. What can be done to treatit, and most importantly, to prevent it. Perhaps it would be best to begin exploring what what is abnormal by understanding what is normal for non human primates.
Love is defined as the affectionate feeling for others. For nonhuman primates, perhaps it is better to label this affection as bonding. This affection or bonding can be defined as "systems" in monkeys, and can be approached in five distinct ways. All these systems overlap, preparing the individual for the next in the sequence of a normal life. Each system must be allowed to progress normally, for if one is interrupted, a monkey is then deprived of its normal development - its normal progression.The ability to establish proper foundatiuons for future development is lost, yet each level of growth becomes more and more complex as a monkey matures. Normal development of a monkey as a complex process that begins at birth (and can even be affected before birth as we will show later). This first important affecitonal system is the:
These systems work together to give primate life in which security and trust are developed, both by the fulfillment of physical needs, as well as mental or emotional ones. The social aspects of all these systems provide vital experience that determine a monkey's social and reproductive destiny, as well as its degree of psychological wellbeing.
Let's begin at the begining. Earlier, we spoke of the negative effectsof stress on an infant even before birth, while still in the mother's womb. A group of studies can help explain how proper development can be hindered at such an early stage. Along to present all this scientific information in a more readable way is professor T. Arsidae of the Prehensile University (also known as P.U.).
This fascinating group of studies succeeded in demonstrating the negative effects of stress on the unborn infants of mothers in study groups. They were brought inside for ten minutes a day to listen to a load and rather unpleasant noise. This produced a reaction in the mothers in the form of stress. Later, after their infants were born, they were given tests to determine the following:
Study # 1: These infants showed what is called cognitive impairment. In other words, if a familiar object was hidden or partially hidden, the infant had more trouble than a normal infant would have in recognising it, because of impaired development.
Study # 2: Although males and females responded differently, prenatally stressed infants showed higher disturbance behaviour, less climbing, less locomotion and environmental exploration, less play, more clinging behaviour, and more self-directed negative behaviour. These infants even showed a strange reactionby sleeping more, and at inappropriate times.
Study # 3: Showing the negative effects in this study are lower birth weights in prenatally stressed infants, delay in self-feeding, a lower motor maturity, poor muscle tone, poor coordination, and slow response. These infants also showed poor attention spans.
Study # 4: differed in that it used a group of squirrel monkeys to test the effects of long-term prenatal stress on squrell monkey infants. Pregnant females were subjected to disruption of their social relationships. This sustained stress of the mothers and significant effects on the infants' fetal development. It should be noted that a single isolated stressful event did not produce any significant damage.
What we can deduce, therefore, is that stress has a negative physical effect on the development of an unborn monkey, that permanently hurts it, and can be observed after the infant is born. The one direct result of stress that causes this damage has to do with the supply of blood and oxygen to the fetus. Stress interferes with the level of blood pressure, which in turn reduces the oxygen level to the fetus. This lack of oxygen interferes with the growth of the fetus, contributing to subsequent developmental problems. So, you primate caretakers be sure to keep those preganant moms in a stable, secure environment without undue stress.
All the above information is taken from the American Simian Society's handbook "Primate Care" with permission of the editor. I would like to thank the Society for allowing me to use their book to make my page. In place where there is an * is where I have changed the information to suit mainly the South African Condition. Please feel free to email me if you have any qustions, if I don't know the answer I will find out for you!!! My email address is paul.millenaar@vodamail.co.za
