Endangered Primates on Cat Ba Island

The time passes quickly and there is far less time to write personal things then I thought there would be, and so, so much to write about.  I’m sure people would love to know about the amazing array of colorful butterflies and other insects, the brilliant sunsets, the stunning plant diversity, or the stark landscape, but what people are probably most interested in is the langurs.

What are langurs?  This is a question I am often asked.  In the most simple terms, they are a family of Old World leaf eating monkeys in the family Cercopithecidae, with long hands, minimal thumbs, and long, flexible tails used for balance in their acrobatic lives.  The Cat Ba Langur (Trachypithecus poliocephalus poliocephalus) is a highly endangered species of langur found only on Cat Ba Island, Vietnam, a species often confused with, but very distinct from the closely related White-Headed Langur that is found in Guanxi, China.

The Cat Ba Langur has the dubious distinction of regularly being included as one of the top 25 most endangered primates in the world.  This is not a distinction of honor, it is much like being classified as a survivor of genocide  or a citizen of a repressive dictatorial regime.  By endangered I do not mean that there are only a few hundred left, I mean truly, desperately endangered, as in only a small handful left.

There are less than 60 remaining 70 (as of mid-2015) in the wild and only 5 in captivity.

Approximately 16 percent of the total global population of this species is represented in this photo.

Approximately 16 percent of the total global population of the species is represented in this photo.

It is my privilege to be working with this species, in conjunction with a number of remarkable people representing a diverse array of organizations, to keep these animals from going extinct.  This is no easy task, one during which I learn new things every day and must adjust my preconceptions on a regular basis.

From my previous post you, gentle reader, have an idea of the rugged nature of Cat Ba Island, a land of sheer cliffs, wickedly sharp limestone, and convoluted shoreline.

A fjord within the langur sanctuary on Cat Ba Island

A fjord within the langur sanctuary on Cat Ba Island

My work has a strong political component and winds up being largely logistical and administrative, but I am fortunate enough to head-up a small organization where I do get to take part in field-work on a semi-regular basis.  All of our activities are focused on langur conservation, no matter how separate those activities may feel at any given time.  This is both a relief and a pleasure as the region is spectacularly beautiful and the local folks I work with have the souls of gentle and generous giants.

Langurs, as a group, are not large monkeys; the Cat Ba Langur has a body about the size of a small child, but with long limbs and an expressive tail longer than the monkey’s body.  Their expressions are surprisingly deep and soulful, as though they are pondering something we humans have lost sight of, yet are aware of and amused by the conceit of doing so.

Adult langur resting in a tree

Adult langur resting in a tree

The adults are black with white/yellow heads, gray suspender-like lines on their flanks, and wonderful punk-rock hairdos.  The breeding groups are female dominated and small, the largest one being about 16 individuals.  There tends to be one reproducing male per group that is often a little separate from the larger body, keeping watch, and the like.  Females share child-rearing duties, sometimes carrying young of other females, and all members are often in close physical proximity.

Their calls are a mixture of chirps, hoots, coughs, and an amazing deep growling ratchet that echoes from the cliffs and sounds as though it comes from something the size of an overweight gorilla.  I have not managed to record the sound yet, or I would post a copy of it as it really is astounding.

The young are a brilliant orange/gold color when born, a color that slowly fades as they age and provides pretty much the only visually obvious way of determining age for the individuals.  Their markings are so uniform that is is impossible to tell individuals of the same age apart unless one has an obvious injury, which few, fortunately, do.

Infant Cat Ba Langur showing brilliant gold color.

Infant Cat Ba Langur showing brilliant gold color

As the animals age they slowly lose the gold color, starting at at the mid-point in their limbs.  The young remain playful well into adulthood, probably a survival characteristic as play has been demonstrated to be a necessary part of physical and social development.

Langur Cua Dong infant adult sm wtr 215

Monkeys in general and langurs especially have long been recognized as being stunningly agile, highlighting the importance of the physical benefits of extended play time during periods of physical development.  Those of you familiar with Indian mythology will remember the character Hanuman, one of the heroes of the Ramayana (shameless plug:  William Buck’s Ramayana retelling is fantastic reading).  In this tale Hanuman, the Monkey King, Son of the Wind is a god-like figure adept, wise, and agile, embodied with great physical and moral strength, the ability to fly, and one of the most likable, playful , and morally unambiguous characters of this set of nested tales.  Hanuman is thought to be a Gray Langur (aka. Hanuman Langur – Semnopithecus entellus), an agile species bearing a robust beard most mountain-men would be jealous of.

On the landscape of Cat Ba the importance of physical agility absolutely cannot be understated.  Stanley Kubrick once stated, ” The most terrifying fact about the universe is not that it is hostile but that it is indifferent.”  The landscape of Cat Ba is indifferent with a vengeance, in a way that belies the rich tropical vegetation.  Under and frequently poking through that green blanket of life is a landscape of razor-blades that, when the vegetation is stripped away, appears to come from the post-apocalyptic imagination of a science-fiction writer.  This is home to the Cat Ba Langur; the same landscape we humans struggle to navigate while doing field-work the langurs treat with the same casual approach that we treat a trip to the mailbox.

Langur parkour

Langur parkour

What will happen to this species is far from settled and depends heavily on far more than our work.  It depends on the education, support, and involvement of a far larger society.  If any of you feel the drive to support the conservation of a beautiful and heart-rendingly rare species please take up arms.  It doesn’t need to be this particular one, the world is, unfortunately, full of non-human species of all kingdoms that would benefit from your support.  Some are photogenic species such as this langur, others are innocuous plants or insects.  Some are found in exotic locations like this limestone island in northern Vietnam, others may literally be in your backyard.

These primates have suffered a 98 percent population crash as a result of hunting for traditional medicines, habitat destruction, and several other pressures.  There were never very many, we cannot speculate about their peak numbers, but during the 1960s there were between 2500 and 2700 on the island.  When our project started in 2000 there between 40 and 53 left alive in the world (surveys are difficult on the island and early surveys relied heavily on local people’s statements).  Very little is known about this species and we are desperately trying to increase that body of knowledge as we do our conservation work.  Fundamental questions are still unanswered and the challenges of field-work in this environment impose severe limitations on many traditional methods of study.

For those of you who feel compelled to support our project, we welcome you: our project is the Cat Ba Langur Conservation Project (please excuse how out of date the website is, our attention has been focused on more pressing concerns) and I can be reached at the following address: neahga.leonard@catbalangur.de

If you are visiting Cat Ba, come say hello.

Juvenile Cat Ba Langur portrait

Juvenile Cat Ba Langur portrait

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The first month on Cat Ba Island – getting my bearings

My apologies for the long gap between posts, life has been a bit busy.

I recently began a new position in Vietnam, on Cat Ba Island to be specific.  My first impressions are that this is a damp and precipitous landscape.  I have not seen the sun since I arrived in Vietnam on March 4th.  For Cat Ba Island this means a riotous profusion of greenery tempered by the steep terrain and lack of soil.

Where the northern end of the road terminates

Where the northern end of the road terminates

This is a land where Ymir’s bones lie close to the surface, broken and weathered, their calcium leaking back into the waters from which these precipitous cliffs rise.  The geology is the first thing that strikes you here.  The cliffs have been weathered by millions of years of rain, the ever-so-slightly acid rainwater eating into the ancient limestone creating a mature karst landscape.  Like bones, coral, and seashells, limestone is primarily made up of calcium carbonate, which in other forms makes marble and dolomite.  This is probably one of the reasons this is a place where snail diversity is immense, ranging from tiny frilled creatures more akin to limpets to giant land snails, many of which are still unknown to science.  Snails need lots of calcium to make their shells.

Unknown frill terrestrial snail

Unknown frilly terrestrial snail

Land snail shells collected around the office - and a wasp nest

Land snail shells collected around the office – and a wasp nest

The banded limestone found here is a relic of abundant diatom (a type of plankton) skeletons laid down five hundred million yeas ago and subjected to the vagaries of time.  Limestone, while soft to the chisel and hammer, is a remarkably durable stone at the macro-scale, one of the reasons climbers like it, but at a chemical level it is easily weathered.  We are often told that water has a pH of 7, that is it neutral.  Natural rainwater, we then assume, should also have a pH of 7, but it is closer to 5.6 due to the dissolution of carbon dioxide into the water making carbonic acid.  A pH of 5.6 is about as acidic as a cucumber or an onion for comparison.  Of course, other environmental factors can reduce this tremendously, leading to extremely acidic rain.  Rain falling on the limestone erodes small channels in the rock that look like thumbprints in wet clay.

Rainwater erosion on limestone

Rainwater erosion on limestone

Eventually these concentrate water flow, carving small holes in the stone reducing it to a swiss-cheese like structure with an extremely jagged and sharp exposed surface.  These little caves connect into larger caves.  In these protected, damp environments bacteria grow, exuding waste products and creating hydrogen sulfide that mixes with the water and makes a weak sulfuric acid, increasing the chemical weathering.  This cycle persists, eventually leading to enormous caves.

The airflow in these caves evaporates the mineral rich water tricking through the now porous stone and the calcium carbonate re-solidifies into stalagmites, stalactites, soda straws, and any number of strangely beautiful and complex cave structures.

Caves often form in weak portions of the stone and, eventually, gravity takes its toll and the weakened rocks collapse leaving behind steep spires and fields of slowly eroding boulders.

Limestone spi

Limestone spire in the north end of Cat Ba Island

Cat Ba and Ha Long Bay are examples of a drowned karst landscape, a mature karst landscape that has been flooded by rising waters.  What little soil does form is washed down into the many bays, coves, and channels of the region, leaving little for plants to sink roots into.  In the shallow waters of the bays mangroves find nutrients, in abundance.  Here mangroves are near the northern margin of their range, their numbers restricted and the trees short, making low dense forests.

Gray mangroves on the south western side of the island

Gray mangroves (Avicennia marina) on the south western side of the island

As in many places, the mangroves are in trouble here, often cut down to make shrimp farms.  This leads to reduction in local fisheries, increased erosion, and lack of protection from storm surges and tsunamis.  The local government is taking steps to protect what remains and to, potentially, restore some of the previous mangrove forests.  In the rich mud of the mangrove regions there are numerous animals, among them one of my favorites, mudskippers, amphibious fish that hop about in the mud protecting their little territories.

Mudskipper amongst mangrove roots

Mudskipper amongst mangrove roots

On the cliffs however there are few nutrients and plants grow in what cracks and declivities they can find.  As per many islands there are a number of endemic species, here one of the most commonly seen ones is the Ha Long Cycad (Cycas tropophylla), an ancient type of gymnosperm that looks like a cross between a fern and a palm tree.

Ha Long Cycad (Cycas tropophylla), endemic to a 400km square area, globally rare, locally abundant

Ha Long Cycad (Cycas tropophylla), endemic to a 400 square km area, globally rare, locally abundant

The season here is shifting into spring and some of the trees have begun blooming, among them the hoa gạo or Cotton Tree (Bombax ceiba), so named for the kapok-like fibers that are found in the seed pod.

Hoa Gạo (Bombax ceiba), Cotton Tree in English.  The Vietnamese name translates to "Rice Flower"

Hoa Gạo (Bombax ceiba), Cotton Tree in English. The Vietnamese name translates to “Rice Flower”

 

I still have not seen the little primates I came here to work with, they are few in number and they clamber about on the vertical cliffs like, well, monkeys.

Soon though.

A New Job, a New Voyage, An Endangered Species

The rain has finally come to California, bringing with it the promise of new growth and greenery.  As it rains outside the window I am inside,  surrounded by loosely organized piles of clothes, books, outdoor gear, and laptop peripherals attempting to fit my life into two 20kg bags.  Before I go I need to take care of all those technological tasks our life is filled with as well, back up my computers, transfer my iPhone and iPad to a different computer (Apple, you really need to make that easier to do), and do the final run-through on what I am taking with me.  Despite all this, my mind is only partially on the task at hand.

Several weeks ago I was offered a position working on primate conservation in northern Vietnam and my mind is on the location, the people I will be working with, and the upcoming tasks.

The Gulf of Tonkin - NASA image

Northern Vietnam, Southern China, and the Gulf of Tonkin – NASA image

This is exciting, not in the least because Vietnam, like much of South East Asia, (and Southern China) lies firmly in one of the great biodiversity hotspots of the world.  Northern Vietnam is on the edge of Sundaland, a name for the vast expanse of what used to be land connecting the Southeast Asian mainland to Borneo and the Indonesian islands, now mainly under water and expressed as the Sunda Shelf.  During the last ice age this is thought to have been a broad grassland spotted with mountain forests and laced with broad rivers.  For nearly 100,000 years plants and animals moved back and forth across this landscape, becoming wide-spread and subsequently isolated as the rising seas flooded the lowlands, leaving the complex arrangement of islands and peninsulas we now see.

This exposure and inundation of land in this part of the world has been taking place for a long time.  This combined with the vigorous tectonic activity of the region has led to a wonderfully complex region topographically, and subsequently (or in conjunction) biologically.

Sundaland showing current and proposed past rivers

Sundaland showing current and proposed past rivers (source)

This submerged region is now thought to be the cradle of the Asian population, the “Out of Sundaland Theory”, although there is a competing “Out of Taiwan Theory” as well.  Where I will be working is only loosely in former Sundaland, a melding point between Sundaland and the complex geography of Southern China and Northern Laos.  In any event hominids, and later humans have been exploring and living in South East Asia for a long time, and that span of time has allowed tremendous cultural and linguistic complexity to develop as well.  This is one of the places that our most successful and long-lived hominid ancestors, Homo erectus, lived.

I will be on the edge of this region, just off the coast of northern Vietnam, on the northern margin of the Red River delta not too far from the Chinese border.  The location is Ha Long Bay, a dramatic karst landscape that is both mature and submerged.  The ingredients for a karst landscape are limestone and time, lots of both.  In some parts of the world the only signifying features of kart landscapes are rich soils (lots of cations) and , if it is wet, periodic sinkholes.  Where water is in abundance caves are common, as groundwater is often mildly acidic which erodes the limestone.  Over time continued erosion wears down the limestone bedrock to such a great degree that all that is left are startlingly steep sided hills, separated by flat valleys.  This is a mature karst landscape.  In Sundaland some of these mature karst regions were flooded when the sea level rose resulting in a dream-like landscape that looks like something Hayao Miyazaki would imagine if he were to direct a pirate movie.

Ha Long Bay mature submerged karst landscape (source)

Places like Ha Long Bay are excellent examples of island biogeography.  Islands are often home to endemic species, the tortoises and finches on the Galapagos Islands are the classic example of this, made famous by Darwin.  Animals and plants that make their way to an island, or are trapped by rising seas or continental drift become isolated and diverge from their ancestors.  This is the essence of island biogeography and the recognition of how finch beaks on the Galapagos changed in response to the limited food sources available on the islands helped Darwin to recognize how evolution takes place.  My personal hero in the tale of evolution, Wallace, worked in the submerged island remnants of Sundaland and experienced the same insights as Darwin.  Ha Long Bay is a small area, but has its own endemic species, many of them we probably know little to nothing about.

One we do know of is the Cat Ba Langur (Trachypithecus poliocephalus poliocephalus), a dark haired leaf eating monkey with white heads and brilliant golden furred babies.  They are found only on Cat Ba Island, one of the largest islands in the Ha Long Bay, and are critically endangered.  Critically is an understatement, there are less than a hundred of these primates alive in the world.  And. That. Is. All. There. Are.

Cat Ba Langur on limestone cliffs. [EDIT – the photo I previously had here was of the closely related White-Headed Langur – it was mislabeled as a Cat Ba Langue at the source I found it]

In 25 hours I get on a flight to Hanoi to take part in an effort to both keep these primates from going extinct and to conserve the biodiversity of the island.  There are a lot of moving parts in the project, many partners at all levels, and only a few of us on the ground to keep everything running smoothly.

I’m excited, eager, and somewhat intimated.  I leave tomorrow.