Fact Attack: Endangered Species No. 105 – Northern Muriqui

Northern muriqui (Brachyteles hypoxanthus) family play by Peter Schoen

Man has been endowed with reason, with the power to create, so that he can add to what he’s been given. But up to now he hasn’t been a creator, only a destroyer. Forests keep disappearing, rivers dry up, wild life’s become extinct, the climate’s ruined and the land grows poorer and uglier every day.
Anton Chekhov

Northern muriqui (Brachyteles hypoxanthus) by Bart van DorpThe muriqui, the largest of all New World primates, has recently been divided into two separate species. Both species are considered at risk of extinction. The northern muriqui (Brachyteles hypoxanthus) is listed by the IUCN as Critically Endangered and the southern muriqui (Brachyteles arachnoides) as Endangered.

And, all because the Atlantic forests of Brazil have been, and continue to be, relentlessly and indiscriminately hacked down to make room for crops such as Devastated rainforest in São Paulocoffee, sugarcane, palm (hearts) and tobacco. Mining for rock, like bauxite and granite for instance, has reeked havoc, too. And, as if that is not enough, vast swathes of land have been cleared and given over to grazing cattle. Needless to say, all the human requirements  that go with this rampant destruction have greedily devoured enormous slices of the precious and essential forests as well.

Slash-and-burn agriculture was, in fact, banned in Brazil over forty years ago, but the effects of this horrendous vandalism are still in evidence. Charred plant material is seeping from the soil into the rivers and thus into the ocean, potentially harming marine life.

But loss of habitat, although major, is not the only threat to the muriquis.

Northern muriqui by Peter SchoenThere is also the ubiquitous and questionable propensity for hunting. Muriquis have been heavily hunted for food and sport since the 16th century, when the Europeans first settled in São Paulo State. Something which continues to some extent today. The docile muriqui are active during the day and gather in large groups, and they are large of body, making them easy to spot in the trees. Each individual is big enough to provide the average family with more than one good meal. So, you can see their appeal to the less scrupulous. But with their current status, killing even one animal could be devastating to the smaller populations. Where once they were plentiful, there are now less than one thousand left in the wild, and some of those inhabit extremely isolated and fragmented forest areas. Their chances of long-term survival, at best, are not favourable.

Hunting of muriquis, whether for food or sport, is illegal, but still persists. To add to the crisis, many locals have also captured infant muriquis and kept them as pets.

Northern muriqui (Brachyteles hypoxanthus) by Bart van Dorp Northern muriquis have long limbs and long, fully prehensile tails. The combination allows for optimum agility when moving through the trees. Males and females are almost identical in appearance with coats of brownish-grey and marked faces. Babies are born with black faces which then become mottled with age, developing typical pink blotches. Males and females are also roughly identical in size. Adult males weigh in at an average twenty-seven pounds and can extend to almost five feet from the head to the end of the tail.

Biologically, the most significant difference between the southern and northern muriqui is the presence of a small opposable thumb in the latter. This thumb is vestigial, possibly due to the development of its prehensile tail which may have gradually rendered the thumb superfluous to requirements.

Northern muriqui Both arboreal and diurnal, muriquis live in mixed troops of up to eighty individuals. Unusually for primates, they are not territorial and little aggression is ever displayed between members of the troop. Indeed, they are rather affectionate toward each other. Although they don’t seem to indulge in a lot of social grooming, a great deal of hugging does take place.

The also travel in line, one after the other, when moving through the forest. All very organised and orderly. A bit like following in the footsteps of someone else through a minefield. Those behind will always be in less danger. In this case from falls, the branches have already been tested by those in front, and from predators; alarm calls will soon be raised by those ahead who see them first.

This species is promiscuous, and mating is at a high from September to March, ensuring births occur in May to September during the dry season. Twins are rare, and most mothers give birth to only one infant. The infant will be born altricial and its care will only ever fall to its mother. Fathers do not tend to get involved, possibly due to paternity issues.

Northern muriqui - National GeographicInfants will only be weaned between the ages of eighteen and thirty months, and it will be between six and eleven years before they are mature enough to reproduce. Until weaning is complete, mother and child enjoy a close relationship, which then ends abruptly with the mother chasing her offspring away. Again, unusually for primates, it is the males which remain within the natal birth troop, with females leaving to join other troops.

It is not known how long muriquis live in the wild, but this long attachment to the mother, such late maturity and an average inter-birth interval of three years, can surely only hamper any rapid increase in the populations.

Northern muriqui stampsTo its great credit, the muriqui has become a symbol of the Atlantic Forest and its vastly rich biodiversity. It now appears on postage stamps, t-shirts and posters. Its peaceful and tolerant reputation has also earned it a place on the short list of mascots for the 2016 Olympic Games.

Natural Habitat
Humid coastal forests.
Brazil’s Atlantic Forest.
What they eat
Young leaves, fruit and flowers.  When needs must, they will also eat birds’ eggs and some insects. 
Habitat destruction (the species now survives in extremely reduced and isolated populations). Locals hunt the muriqui for food, and they are sometimes hunted for sport. Natural predators include such as raptors and jaguars, but these are not seen as a huge threat as there is little else to attract them to the fragmented forests the muriqui inhabits.
Status: Critically Endangered
The Northern muriqui (Brachyteles hypoxanthus) is listed on the IUCN Red List of Threatened Species as Critically Endangered. It is also listed on Appendix I of CITES.
Scientists have applied a species prioritization scheme, the ‘National Action Plan for the conservation of Central Atlantic Forest Mammals’, to include the northern muriqui. Plans include habitat conservation and restoration, and establishment of green corridors. More of this can be found at ICMBio.
The green corridors will be created to link the few remaining fragments of forest. There are thought to be less than one thousand individuals left in these isolated parts. This species has shockingly suffered a decline in numbers of over eighty per cent over the last three generations.

Captive breeding programmes are in place.

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Fast Fact Attack: Endangered Species No. 94 – The Golden Lion Tamarin

Family portrait

 “In simple terms, the rainforests, which encircle the world, are our very life-support system – and we are on the verge of switching it off.”
Charles, Prince of Wales

Golden lion tamarins take their name from the magnificent ‘mane’ of golden hair around their necks – bearing a remarkable resemblance to the lions of Africa.  There are four species of lion tamarins – all of which are endangered, and all of which are endemic to Brazil.

Golden lion tamarin foragingEach species is blighted with the same major threats to its survival; loss of homes due to illegal logging, haphazard cattle ranching and human settlement.  Shockingly, the lion tamarins have now been left with only eight per cent of their original habitat.  Put another way, a staggering ninety-two per cent of their native Atlantic Brazilian forest has been burned or felled. This has jeopardised their freedom to roam for food, shelter and genetically diverse mates, rendering them one of the most endangered species on the planet.

Colonisation is not new to the Atlantic forest. Europeans first settled here in the 1500s. Historically, destruction began with coffee and sugarcane plantations.  During the 18th and 19th centuries demand was high for both commodities, heights matched only by the devastation caused by these activities. Despite this, today’s damage far surpasses anything achieved previously.

Current deforestation has created a specific danger for young golden lions.  These highly sociable little animals are far more exposed in their ‘play areas’ than before, making them vulnerable to predators.  Over forty per cent of Golden lion tamarin feedingjuvenile tamarins do not live past one year, even in normal circumstances, and this can only add to the difficulties of re-populating the troops.  The average lifespan of any golden lion tamarin surviving the age of one, in the wild, is fifteen years.

There are several conservation programs designed to combat the decline of the species in the wild.  Animals have been reintroduced from various worldwide captive breeding programs, which incidentally move individuals among the various zoos to prevent inbreeding. Survival rates have been notable, but their habitat is now so sparse, the problem with finding suitable homes and feeding grounds has not abated.

Fortunately, tourism has also begun to play its part, using the golden lions as a an attraction to be seen rather than harmed.  This can only be  a step in the right direction.

Also known as golden marmosets, the golden lion tamarins are easily recognized New World monkeys that sport a vivid orangey-red coat, with a long mane surrounding a hairless face of dark, rich purple.  It has been said that the colour of the coat may have come from direct exposure to sunlight coupled with carotenids in the diet.

Golden lion tamarin climbing a tree Golden lion tamarins are callitrichids, which have the defining characteristic of claw-like fingernails on all digits except the hallux (big toe).  These adaptations aid climbing, clinging to tree trunks in vertical fashion, quadrupedal movement through the branches and feeding.  Both male and female are similar in size reaching a height of about ten inches and weighing an average of one and a half pounds.

Golden lions are arboreal, sleeping in tree hollows at night hoping for some protection from predators.  Unfortunately, nocturnal predators, such as snakes and wild cats, often get the better of them.  When one monkey sees a predator, an alarm call is emitted to warn the rest of the troop.  Sadly, this is often too late.

A golden lion tamarin dad , front and back, rare twin babies, Brandywine Zoo, Wilmington, Delaware.These tamarins, like the others,  are omnivorous and travel through the branches (at up to 24 miles per hour, no less) to forage during the day.  They live in troops of anything up to nine individuals and often these delightful primates share food with each other. Normally these troops would be made up of a male, a female and some younger members of the family.

Lion tamarins are monogamous and mating usually takes place at the end of the rains (March to June), after which there is a gestation period of four months.  The species is unusual in that twins are normally born.  Most primates will give birth to a single infant.  Three and four babies have also been known to be birthed, but the chances of survival of all are quite remote.  The weakest will usually go first.  All group members, especially the father, will help with the care of the babies.  Infants are totally dependent on their mothers for the first four weeks.  At five weeks they will become a tad more independent and start to explore their surrounding, but still keeping close to mother.  Seventeen weeks will see them socialising with others in the troop, and at the age of fourteen months they will be considered young adults.

Natural Habitat
Coastal primary tropical forests.
The diminishing Atlantic coastal forests of Brazil.
What they eat
Soft fruits, insects, flowers, nectar, eggs, invertebrates and small vertebrates.
Habitat loss and fragmentation due to aggressive logging, reckless agriculture and extensive human settlement.  Loss of suitable habitat has made reintroduction to the wild difficult because of the lack of sufficient clustered trees.   Though more than four hundred animals have been reintroduced into Brazil since 1984.   Capture for the illegal pet trade seriously depleted populations in the past, however,  this practice has lessened since laws were passed making the keeping of exotic pets illegal. But, it has not ceased.  Natural predators include birds of prey, snakes and wild cats.
Status: Endangered
The golden lion tamarin  (Leontopithecus rosalia)  is listed on the  IUCN Red List of Threatened Species  as Endangered.  It is also included on the  Brazilian Official List of Species Threatened with Extinction  (Lista Oficial de Espécies Brasileiras Ameaçadas de Extinção)  and on the regional threatened species list of the state of Rio de Janeiro.  The golden lion tamarin is protected under CITES Appendix I.
Dedicated conservation efforts have brought the numbers of golden lion tamarins from less than two hundred in the wild in the early 1970s, to over fifteen hundred living in the forests today.
Approximately four hundred and fifty are known to be living in one hundred and fifty zoos around the world.
Various conservation measures and programmes are in place, including  the National Zoo 

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