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Transcript
Internet Article: http://www.fieldtripearth.org/article.xml?id=1290&ordinal=1
From Site: FieldTripEarth.org
Referenced: 1/2/09
Searching for Wild Chinchillas
by Amy Deane
January 23, 2008
Page 1 : The Search
Atop a ladder, which has all four legs in buckets of water to deter poisonous critters from reaching me, I await nightfall.
After a decade of studying wild chinchillas, I still have really not seen one. Their natural history makes these little
mammals hard for researchers to observe. They are nocturnal, perhaps to escape some predation pressures or to avoid
the heat of the hot arid days here in these cacti- covered transverse mountains of Northcentral Chile. Tonight, I am not
only nocturnal but am armed with Russian defense technology (infrared night-vision binoculars, that is). I have never
been close enough to describe in detail their behavior. However, the locals assure me that, if I just try this one spot, I will
see elusive endangered chinchillas up close and personal. So, I sit and wait for nightfall.
Tonight seems like all other nights out in the mountains—cold, very dark and peaceful. The first two animals I see are
European rabbits, an exotic species that causes many problems in this area. At 9:40, a rustling noise starts from behind
me in the bushes. Still, I keep the night-vision binoculars focused on the stone fence ruins where the chinchillas are said
to be living. Every couple of minutes, I turn the lens toward the noise but detect nothing.
The noise is now off a little further, but upslope and to the right. Once again I turn the lens and see nothing. I know
something is stalking me and I am hoping with all my might that it’s not a puma. I have seen their tracks in this basin but
I reassure myself that cats are quiet. Still no chinchillas.
At 10:00 pm, the noise is getting louder as the animal approaches from the right. It skids to a stop. Relieved that
whatever I am going to see has not yet attacked, I turn the binoculars and see a pair of large green eyes that belong to a
very skinny fox that is gazing up at me. Instead of being scared, I find myself laughing at the little one. Poor guy, no
wonder he’s so skinny—I have heard him approaching for 20 minutes. Also, this is probably why I still have yet to see a
wild chinchilla!
The fox walks down toward the trees and marks the closest one with urine. By the time I have refocused on the chinchilla
colony, the fox has returned and is now to my left. I watch the fox watch me for a couple of minutes. He turns his head
vertically to look at me as if he is unsure of what he sees. It is a chilla fox ( Pseudalopex griseus). This species is the
smaller of two fox species found in the area; both prey on chinchillas.
When hiking, I usually stop to watch foxes. They also pause for a second when they first detect my presence and then
they run off. Tonight, I glance down at this fox and decide to move up the ladder one more step to avoid the nuisance of
having to go though yet another set of rabies shots. Not that I really think he will bite me. He leaves.
I turn the binoculars back to the ruins and watch for another hour and fifty minutes. My spirit is dampening; it seemed
that I was never going to be able to study wild chinchilla behavior. Of course, I can keep doing what I’ve been doing,
which is just making habitat. I can find their feces, get their footprints, and even hear them occasionally; but I want to
see them. Not only for science, but for my personal satisfaction. By 11:50, I have given up on seeing a chinchilla. Tonight
is going to end as all other nights, with only more data on non-chinchilla species to show for my work.
At 11:55 pm, two little green flashes of light appear in my binoculars. I blink to clear my vision. It is the left eye of a
small animal. The animal hops twice, and pauses upon a large rock for a few seconds. It stops long enough for me to
focus in on the tail. And this time, the tail is long and bushy. It is a chinchilla! A WILD CHINCHILLA!
My neighbors were right; I could see the entire body and ears of an adult chinchilla. Then it hops to a small bush where
another adult chinchilla is sitting. Their eyes are opening and shutting, and the animals appear to be rolling. At least one
of them is taking a dust bath. Chinchillas love to roll in dirt. It keeps their fur clean and the dust serves as insulation.
Other self-grooming behaviors include face washing with the forepaws and scratching by a claw in the inner digit of the
hind legs.
Page 2 : Observing and Understanding Chinchilla Behavior
Another very small chinchilla hops down from the origin of the first chinchilla and joins the other two chinchillas at the
meeting bush. When the baby reaches the first two, they greet each other by smelling the nose/mouth area; then, one of
the adults one grooms the younger animal.
This greeting is classic for chinchillas. This behavior not only identifies individuals, but also may be an act of submission
and probably helps to maintain social bonds, as greeting individuals participate in allogrooming. Grooming sessions can
last for minutes and may lead to sexual acts. As with everybody, chinchillas love to be groomed when they want to be
groomed. In general, they are not like a dog that loves to be cuddled.
In captivity, females control sexual behavior. Males vocalize and wag their tails to get the attention of a female. Once a
male has mounted a female, usually she moves before he has completed copulation. If the male does not leave her
alone, she may stand up on her hind legs, chatter her teeth and spray him with urine.
Their reproductive biology is why chinchillas have not been able to quickly recover from endangerment. Like many
endangered animals, chinchillas have a small litter size, long period until they reach sexual maturity and a long period of
gestation. Thus, they are not able to undergo rapid population growth.
Chinchillas' gestation period lasts 111 days. One or two young are born with eyes open, fully furred and active or
precocial. Sexual maturity is reached around eight months of age. Females can have up to two litters per year. In other
words, when compared to other rodents, chinchillas have long gestation periods that result in few offspring. Neonatal
weight of chinchillas is 35 grams. The breeding season for chinchillas is at the onset of spring in Chile. Despite the
creation of Reserva Nacional Las Chinchillas (a national reserve to protect chinchillas) 24 years ago, the animal has not
re-established itself. Populations within the reserve continue to decline, and nobody is certain why they are declining.
Page 3 : Play and Space-Sharing Among Chinchillas
Many people who have pet chinchillas notice that chinchillas urinate in a particular corner of their cage or play area. The
domestic chinchillas that I care for have a common playroom. One group plays for a while and then I place them in their
cage and let another group play. Individuals are grouped by allowing any chinchilla to play with any others as long as no
fights break out.
It has been my experience that all family members can be grouped together for about the first two years of a juvenile’s
life. In fact, juveniles can play with almost any group for the first couple of years. At this age, if the juvenile is male,
other adult males, including his father, will start to fight with him—they probably perceive a young male as reproductive
competition. However, related females seem not to show aggression toward each other. This does lean evidence toward
the assumption that, in the wild, young males disperse from their natal colony.
Also during playtime, I have noticed that all the males, and even some females, spend an enormous amount of time
smelling the urine left by others. This probably relays information on the identity and reproductive state of individuals. Or,
this may in fact be a territorial marking. Exactly how chinchillas allocate defended space in the wild is unknown. I have
never read any reports of chinchillas using scent markings to define territories but I believe it is highly possible.
One night at playtime, my chinchilla “Squash” spent an extended period of time smelling a previously marked area. He
then lifted up his forepaws, scooted forward in a crouched position and marked the area of interest with no more than
five drops of urine.
Even after a decade of playtime, I am still amazed by what I learn from these guys. Three years back, two female Degus
came to live with the chinchillas and me. Thus, I am unsure if Squash marked upon a chinchilla or a degus scent. Either
way, it's very interesting because wild degus and chinchillas can be found under the same bushes.
They share space by allocating time. Degus are active during the day and chinchillas are active at night. In captivity, most
interactions between these two species are neutral, but negative interactions can consist of a male chinchilla pouncing
upon and sometimes biting a degus. Then the chinchilla bounds away, with the degus sometimes chasing after it in rage.
The female chinchillas seem to be more accepting of the degus. On occasion, degus and chinchillas will groom each
other. In the wild, both newborn chinchillas and chinchilla rats (Abrocoma bennetti) have been found in the same nest.
The wild chinchillas were out of sight for a couple of minutes and I searched for any circles of green lights to appear. A
juvenile chinchilla hopped down from the fencetop, past the rock and towards a bush off to the right. Upon its arrival, it
quickly changed directions and ran upslope to the right. Another small juvenile chinchilla was chasing it. Although this
may have been a real dominance displacement and even territory defense, it appeared to me as though they were
playing. Either way, the games of childhood prepare one for adulthood.
Page 4 : Protecting Themselves From Predators
Chinchillas have a variety of defense mechanisms. A basic one is to flee. They flee not only from predators but also from
other, more dominant chinchillas. In the wild, land tenure is vital for survival. Each animal needs a territory that contains
enough food and shelter. For all of these resources, wild chinchillas will fight fiercely. Entering upon another's area may
even lead to ones death!
Upon rediscovery of wild chinchillas in the 1975, researchers began to study the population. A woman named Connie
Mohlis was live trapping and releasing animals to obtain a population estimates, and Jaime Rodriguez reported on one
particular event. Upon release, a chinchilla entered a nearby burrow. Unfortunately another chinchilla was already taking
up that space. A violent fight broke out. The intruding chinchilla eventually died from wounds inflicted during this fight.
Chinchilla pet owners may notice a frisky hop form of locomotion. This we see and interpret as the animal being really
excited and happy. According to Dr. Kleinman, this rapid hopping movement, with many twists and turns, is probably
derived from chinchillas trying to confuse predators and escape predation.
If unable to get away, a typical defense response begins with the animal standing up on its hind legs. Dr. Eisenberg
writes that this has two motivations: 1) it makes the individual appear larger and 2) it adds confusion to the intruder by
adding a contrasting pattern to the situation. When standing, the animal often vocalizes, showing off its piercing teeth. At
this point, a chinchilla has a couple of options. Sometimes, when a chinchilla is not threatened but annoyed, it may use it
paws to push away the nuisance and emit a brief grunting noise. If really threatened, an airborne urine attack is a
specialty of both sexes, and may be accompanied by the release of odors from the anal glands. If urinating has not
deterred the opponent, those razor sharp incisors will bite it. And, if the adversary chooses to bite the chinchilla, it had
better get a deep grip all the way to the skin, or the chinchilla will just release its fur and hop away.
A while later, an adult was hopping downslope from the same location where I detected the escaping juvenile. The adult
hopped about five meters and stopped. Then the juvenile hopped down and met the adult. The larger one then hopped
another five meters or so and once again stopped and waited for the youngster. This was repeated countless times—and,
both were using the same paths. One of the paths ends or begins at an opening in a large bolder crevice. The adult
entered the rocks, but the baby stayed out hopping near a large rock downslope and left of the entrance.
Domestic chinchillas and their offspring have almost constant vocal contact. I was too far way to hear the wild ones.
However, it’s not too hard to imagine that the adult and young wild chinchillas were communicating by both visual and
auditory means.
In the north/south facing valleys, from what I have seen so far, prey species wait until the moon passes over the
mountain before they come out. This is when their area of activity are in the full shade of the facing mountain.
Otherwise, animals like these tend to be active before the moon rises over the nearby mountains. Tonight was the first
time I was trying to observe chinchillas in an east/west facing valley. The appearance of the moon over the mountain
range to the east lessened my hopes. But, to my great surprise, one chinchilla was still within sight under the meeting
bush.
Page 5 : Threats to Chinchillas
I heard no less than 100 gunshots in the last hour. People had begun to hunt rabbits about two kilometers away. The
gunshots must have stressed the burros and one started to bray. It was at least a kilometer away, if not two, but the
chinchilla was alert to the sounds. It stopped what it was doing and stood up on its hind legs, and listened.
A little later, an adult was eating dried grass, the chinchilla’s preferred food, in an area just down off the stone ruins. A
meter to the left was a break in the fence wall. A trail crossed the fence line at this point. The chinchilla was on my side
of the fence down to the right. From atop the ladder I could see the entire valley, down past the fence. But the chinchilla
could not see well from his spot.
About five minutes passed and then a different type of eye appeared. It was just past the break in the fence and to the
left of the trail. I was frightened for the little chinchilla. The new eyes belonged to a flying animal. The animal flew up
into the sky, about two meters high, and then returned to its original place. It repeated this twice.
Was it an owl? Was it stalking the chinchilla? I have seen great horned owls ( Bubo virginianus) perched on the ground.
After two minutes, the chinchilla stopped eating and hopped to the left toward the other eyes. I could see the new pair of
eyes through the left eyepiece of the night vision binoculars and the chinchilla through the right lens. The chinchilla
stopped at the onset of the trail behind a rock. It then stood on its hind legs and looked over at the eyes. The chinchilla
knew right where the animal was located. It must have used its big ears for that. It took a glance and then hopped right
past it!
The chinchilla knew that the other animal was not a threat. The eyes belonged to an insect-eating nocturnal bird, the
band-winged nightjar (Caprimulgus longirostris). I was awestruck at the nocturnal activity here in the desert wilderness.
Not only did I get to really see chinchillas, I learned that they knew whom not to be afraid of. I did not expect to witness
a chinchilla recognizing a non-predator, at least not the first time I really saw the wild ones.
About Amy Deane
I am the leader of a habitat restoration project in the mountains of northcentral Chile, home of the elusive endangered
chinchilla. After completing a Master's degree in Geography (with a minor in Wildlife Conservation Techniques), I moved
to Chile to begin restoration of wild chinchilla habitat. My introduction to wildlife fieldwork began as a graduate student,
while working on forest songbird nest predation studies. Projects I have worked on include: compiling a GIS database
system of Auco, Chile; creating a GIS/GPS data layer of burn compartments within the Catharine Ordway Nature
Preserve; mapping the study area for endangered Darwin’s fox study near Castro, Chile.
My work has been included in both popular and scientific publications. In Chile, I have walked the mountains collecting
seeds to grow in a nursery, and have guided the planting of 6500 seedlings. I formed Save the Wild Chinchillas in 1996.
My long-term goal is to open a field school to ensure continuing long-term research, preservation and restoration of the
chinchillas’ landscape.
Page 6 : About the Restoration Project
Our goal is to restore essential habitat for endangered chinchillas while deterring habitat degradation in this ecosystem.
Specifically, we will focus on ecosystem restoration in several areas and will utilize native vegetal species, many of which,
like the fauna, are endemic and of grave conservation concern. The use of fuel wood for ore processing and
unsustainable agricultural practices in northcentral Chile has led to desertification. In fact, all areas visited in the project
region have been severely affected due to resource exploitation. Several hill slopes have little vegetation, and hardly any
native tree species can be found.
The second major and current problem is of abandoned farms and free ranging livestock. Although there has been a
dramatic decrease in livestock (9000 animals in 1983 as opposed to 1000 in 2000), and in farms, no one has attempted
to restore native vegetation. Firewood collection for heating and cooking, grazing by livestock and so on has been
persistent. Rabbits and hares, both of which are non-native species, consume the vestigial vegetation essential for native
fauna, especially the endangered long-tailed chinchillas.
Making chinchilla habitat areas
Habitat fragmentation has resulted in creation of isolated habitat patches for all wildlife species, including chinchillas. This
has increased the possibility of extinction for species with small populations and limited mobility. Connecting core habitat
areas to other key areas of habitat will hopefully aid in the stabilization and eventual increase of plant and animal
populations.
Creating habitat by growing native plant species that serve as food, cover and shelter for chinchillas also aids in the
conservation of other animal species in the community, such as Degus (Octodon degus)—which are also called “brush-tail
rats”—the Chinchilla rat (Abrocoma bennetti), and Cururos (Spalacopus cyanus). All of these species only occur here in
central Chile. Many of the plant species are also of conservation concern. By collecting seeds from different localities, we
are ensuring genetic diversity in our plant nurseries.
Project specifics
Our nursery began growing plants for this project in 2000. The seeds are hand-collected and sown in containers that
promote a large root-to-shoot ratio. Having a large ratio is important because we want to promote deep and rapid root
growth once the plant is transplanted. Thus, seedlings have a better chance of establishing themselves before the dry hot
desert summer.
We plan to create at least twelve restoration areas. Each circular area is fenced by barbed wire and has a diameter of 40
meters. One hundred and sixty seedlings are to be placed one meter apart in four main transect lines that cross through
the circle.
An additional 40 seedlings are planted in between these transects. A total of 200 plants per area are planted in two days
by a four-member crew. Holes are dug a little deeper than the seedling container size (which is about 1.5 feet).
The holes are dug with a large crowbar and a tuna can. Then a small amount of soil is backfilled and a handful of topsoil
added. Some natural fertilizer is added, along with some water. The seedling is transferred into the hole and more soil
and water is added.
A dirt semicircle that collects rainwater surface flow is constructed around each seedling and, when large rocks are
available close by, these are placed around the seedling to shade it and also to accumulate condensation for natural
irrigation. Each seedling has a protective fence to guard against predation by rabbits and hares. After planting, each
seedling is measured and tagged to track establishment, growth & survivorship.
Below is a list of animal families that are native to the vegetation communities that we are enhancing. Included is the
number of endangered, vulnerable, and rare species in each family (E=endangered, V=vulnerable, R=rare, I=unknown
status).

Marsupials – 1 species – 1R

Carnivores – 5 species – 2E, 1V, 1I

Rodents – 9 species – 2E, 2V, 1I

Bats – 1 species

Birds – 51 species – 1E, 1V

Reptiles – 8 species – 5V
Plants
This region of Chile hosts at least 209 native plant species, of which 125 are endemic. We are currently growing, or
planning to grow, 14 species to support chinchilla habitat restoration efforts. Of those 14 plant species, three are
endangered and seven are vulnerable.
Page 7 : 16 May 2008 Project Update
Well, this is another La Nina year. That means that conditions here in northcentral Chile are dry. Last year was also dry.
These dry conditions are not good for planting seedlings. Last year we planted late in the wet season and not many of
the seedlings survived. This year, we are trying to transplant seedlings early, before the onset of the rainy season, in
hopes that the roots can establish themselves before the rains begin and the plants can use the rain for above-ground
growth. We will have to wait until next year to see if we are successful.
During El Nino, the opposite of La Nina, we have lots of rain. During these times, most of the smaller rodents have
population explosions. These other rodents can have offspring that have offspring in the same wet season. This is
because they have a short gestation and reach age of first reproduction within a short time frame—some in as little as
month or two. However, the chinchillas have such a long gestation period (111 days) that they do not have these
population explosions. Chinchillas are known as a k-selected species. They have few offspring; instead, they have much
more parental investment both before and after birth.
Thanks for learning about the wild chinchillas. Have a good summer!
Page 8 : 15 October 2008 Update
I have spent the last few months visiting the schools located closest to the wild chinchilla colonies. At each school, I
conduct Leave No Trace workshops (www.lnt.org). None of the students knew that 300 years ago this was woodland with
many trees and even parrots! At the end of the workshop, each student is assigned the task of growing a tree. The
homework assignment is expected to add about 5000 trees to the local area, which has suffered severe widespread
vegetative clearing. For wildlife, these plants provide food, shelter and cover. It is easy to assume that birds will be the
first to benefit from the trees planted in urban areas. These birds are pollinators and seed dispersers for many native
plants that in turn are habitat for the native fauna. Also, adding trees to a compact urban area has many benefits to
humans, such as shade and cooling which are vital in a semi-arid area like ours in Illapel.
At an ecosystem scale, regeneration of local flora is expected to offset desertification, prevent soil erosion, conserve
tenuous water resources, aid in microclimatic cooling, and restore biodiversity. At a global scale, all plants that we restore
collectively act as carbon sinks and contribute towards balance in global biogeochemical cycles. Each student is expected
to grow a tree and write a small report for display at our 1st annual Tree Fair scheduled for November 18 in the city
center (plaza). I got the idea for this from reading about a Tree Scrap Book project in India.
As to our restoration work in chinchilla habitat, I just started collecting seeds for next year’s seedlings. The first plant that
has seeds is Bahia. It is like a dandelion, but in shrub form. And I have taken some cuttings from other species and
began growing seedlings for next year. The seedlings that we transplanted this year are doing very well in all but one
area. We started transplanting seedlings early this year in April. At first we had to water the seedlings until the beginning
of the wet season in May. Then we were very lucky when it rained every weekend. This really helped the seedlings
survive the first couple of months after being transplanted.
Last week was the first time since the end of the rains in August that restoration areas were watered. And almost all of
the seedlings are doing quite well. Each area is fenced with three layers of fencing to exclude keep free-ranging livestock.
However, one area that has been planted three times since 2004 was destroyed when goats got in under the gate. This is
the third time that goats have destroyed this plot. We will plant it again next year and hope for better results.
About the author:
Amy Deane is the leader of a habitat restoration project in the mountains of northcentral Chile,
home of the elusive endangered chinchilla.