Dr. Jim Sanderson on Small Wild Cats & Their Importance
Often overlooked, small wild cats are important and in trouble:
An interview with small cat specialist Dr. Jim Sanderson
Rhett A. Butler, mongabay.com
August 5, 2008
While often over-shadowed by their larger and better-known relatives
like lions, tigers, leopards, and jaguars, small cats are important
indicators of the health of an ecosystem, says a leading small cat
expert who uses camera traps extensively to document and monitor
mammals in the wild.
Dr Jim Sanderson, a scientist with the Small Cat Conservation
Alliance and Conservation International, is working to save some of
the world’s rarest cats, including the Andean cat and Guigna of South
America and the bay, flat-headed, and marbled cats of Southeast Asia.
In the process Sanderson has captured on film some of the planet’s
least seen animals, including some species that have never before
been photographed. He has also found that despite widespread
criticism, some corporate entities are effectively protecting remote
wilderness areas. He cites BHP Billiton’s bauxite project in the
Bakhuys mountains of Suriname as an example.
“If run properly, these sites can be better protected than a national
park because in a national park the public is allowed. In these areas
no one is allowed except the workers and their behavior is tightly
controlled and monitored,” he explained. “So it is pretty easy for me
to see a partnership between industry and the conservationists… In
addition, they have money to support research projects.”
Sanderson has set up a large-scale camera-trapping project that will
monitor the impact of bauxite extraction in BHP Billiton’s 240,000-
hectare concession. Although mining will be limited to a couple
thousand hectares in the concession, Sanderson will use an extensive
collection of images as a baseline to determine how wildlife is
affected by the mining activities. The camera trapping has already
provided Sanderson with insight on the behavior of resident animal
species, including predator-prey relationships, wildlife densities,
and mating and reproductive habits.
“We have pictures of jaguars carrying armadillos in their mouths, and
we have a picture of a puma wrestling a red brocket deer to the
ground. So, we get some indication of what these predators are
eating,” he told mongabay.com. “But we also get mating behavior. We
have repeated pictures of jaguars copulating right in front of the
camera traps. All of these mating-jaguar pictures are taken in May
and June, which turns out to be near the end of the long rainy
season. So we suspect that it’s not true that these animals breed all
year long, but in fact they breed at a certain time of year in
response to rainfall, and have their young several months later
during the dry season.”
Sanderson discussed his success with camera trapping (including his
preference for film over digital cameras), the efforts to save wild
cat species through the Small Cat Conservation Alliance, and small
cat behavior in an interview conducted with mongabay.com in
Paramaribo, the capital city of Suriname.
How you can help
When asked how people can help small cat conservation efforts,
Sanderson said that small cats are typically overlooked by zoos. By
simply asking to see small cats when you visit a zoo, it could help
redirect emphasis and possibly conservation funding towards saving
small cats in the wild.
“Most American Zoological Association (AZA) zoos do not exhibit small
cats because they do not believe the public wants to see them. They
instead exhibit the large and charismatic small cats,” he said. “When
you visit a zoo ask to see something unusual — the small wild cats.”
Donations help too: Wildlife Conservation Network
AN INTERVIEW WITH DR. JIM SANDERSON
Mongabay: What is your background and what sort of work do you do on
Jim Sanderson: I have a PhD in mathematics and was a practicing
mathematician for 20 years. I decided to reeducate myself and because
I became interested in small cat conservation. I went back to school,
got a degree in biology and then started my PhD in wildlife ecology
and conservation at the University of Florida. I actually never
received my PhD because my professor said I already had a PhD and had
already published enough papers. While I was there I co-authored two
books with my professor. One is in its second edition and we are
working on the third edition. Since they basically kicked me out of
the PhD program prematurely, I went to work with Conservation
I had been doing my PhD on the Guigna, which is a small forest cat in
the south of Chile that had never been studied before. All we had to
go on was one picture of one living individual. The total extent of
our knowledge of this cat was that picture and some stomach content
of museum specimens, the last of which had been collected in 1919.
Given these circumstances, people were very discouraging and funding
was almost non-existent, but nevertheless I took a crack at it.
In 1997 I was able to catch one and demonstrate we knew where they
were. A year later I went back and caught eight in thirteen days and
put radio collars on them. This was the first study ever of the
That same year, I went looking for the Andean cat, which is the most
endangered cat in the Americas. The Andean cat had been photographed
twice: once by a professional photographer and once by a tourist from
New Zealand who was traveling in the high Andes. So to start, I had a
picture of an Andean cat taken next to an orange pole. All I knew was
that it was from the north of Chile. Once again people told me I was
crazy, that I would never find this cat, that I would waste a lot of
time and money looking for it. But in fact after about six weeks I
got my first sighting of the cat and when I approached to see it more
closely, it came down to see me more closely. So at 4300 meters
(14,100 feet) I began my pursuit of a cat that was just as curious
about me as I was of it.
The photographs appeared in the National Geographic in February of
2000. Based on those photographs we were able to start a full
conservation program in all four range countries that was funded by
the Wildlife Conservation Network. I am now a partner, one of the
eight partners, of the Wildlife Conservation Network (wildnet.org).
Our Andean cat project is still running there; it’s a very successful
The Small Cat Conservation Alliance (SCCA) was founded in 1996 to
address the conservation needs of small wild cats worldwide
The SCCA’s primary priority species are:
Its secondary priorities are:
African golden cat
Chinese mountain cat
I have been working in Borneo, China, and Sumatra. In China we went
after something called the Chinese mountain cat. Now this is the cat
that was described in 1892 by a Frenchman at the Paris museum. The
skins were purchased during an expedition to China around 1890 and
brought back to the Paris museum where they were identified by a
French mammologist as a species of cat unknown to science. It was the
last new cat to be described.
When we started, we didn’t know where to look. We didn’t know its
habitat and it had never been photographed in the wild. Over the
course of a four year period I went back and forth to China to try to
find where this cat lived. Eventually I came to one village where the
Tibetans were wearing hats made out of this cat so I knew it was up
in the Tibetan plateau somewhere. I gave numerous talks about my
search for this cat and one young Tibetan man said, ‘I’ve seen this
cat. I remember when I was a child my father had skins of this cat. I
am certain that this cat lives around my village.’ He said that it
lived on the eastern side of Tibet, on the escarpment next to
Szechwan. ‘We have to go to my village.’ So we got on a bus. It was
about an eleven-hour bus ride through the mountains of China. We
arrived at his village and people had the cat skins. Nearly every
house we knocked on showed the skin of the Chinese mountain cat. It
was the Holy Grail. So at this point we were able to put out our
camera traps, we knew where to look. The three of us, my Chinese
student, a Tibetan, and I rode on a motorcycle and then walked up
into the hills. We placed our camera traps and got the first pictures
ever of the Chinese mountain cat.
Carlos Driscoll later classified the cat as a sub-species of Felis
silvestris. Therefore it is no longer considered the last cat ever to
be described. That distinction now goes to the Bay cat. The second to
last is the Andean cat.
In Bolivia, Lillian Villalba, Constanza Napolitano, and I were able
to capture an Andean cat at an elevation of 5,400-5,500 meters and
put a radio collar on it. Now 5,400 meters (17,700 feet) is higher
than any point in the continental U.S. This is truly the snow leopard
of the Andes. Or maybe I should say the snow leopard is the Andean
cat of the Himalayas. But this is the most endangered cat in the
Americas and the reason is it doesn’t show any fear of people. The
Chinese mountain cat is afraid of people. It has been hunted to make
accessories like hats, although this practice has now stopped because
of the announcement of the Dali Lama to Tibetans to stop killing
these cats, at least in the village where we were.
But with the Andean cat shows no fear of people and in the high
Andes, the people attribute supernatural powers to the cat. These
powers can be harnessed only if the cats are dead. So they kill the
cats, typically by dropping a rock on them. Or as some people have
described to us, they run up to the cat, throw their coats over it
and then kill it. I have many pictures of Andean cats in small
villages—far more than are in museums around the world, there is one
specimen in the US—of people with these dead, stuffed Andean cats in
their shops as good luck charms. Native Americans adorn them with
silver coins and wool and carry them around as sacred objects. These
charms are called titi and are not sold. They are considered sacred
and are passed down through the family. The Andeans are always
wanting more but these are very rare cats. So we have a conservation
dilemma in that we are trying to save a cat that shows no fear of
people but is coveted as a sacred object. This is a difficult problem
to handle, particularly when the park guards are Native American and
they stone the cat if they find it.
I’m now working on the flat-headed cat and the Bay cat from Southeast
Asia. Both are endangered.
Mongabay: Why did you decide to study small cats?
Jim Sanderson: I found back in the early 80s that all of the big cats
had really been studied, but all of the small cats, which are the
majority of cats, had never been studied. I could open up a book on
wild cats and it would say nothing is known. We know only that it
exists. We don’t know what it eats. We don’t know when it’s active.
We’re not sure of its distribution. So, the small cats were largely
unknown and no one was working on them. All the big cats — tigers,
lions, pumas, jaguars, leopards, cheetahs — had lots of studies. But
the small cats, it was as if they were just left for me to do.
Mongabay: You have some pretty amazing experiences, as far as being
able to find and also catch some of the world’s rarest small cats.
What’s the secret to catching small cats?
Jim Sanderson: You have to have several things. You have to have a
passion what you are doing. Without passion you’re not going to be
successful, because it is not easy. The second quality you have to
have is patience. It turns out I have a lot of patience for these
small cats, and I am willing to wait them out because I know that
I’ll eventually find them. Whereas I don’t have a lot of patience
when I deal with people, I have a lot more patience with animals. So
I would say passion and patience is what it takes. Persistence is
important too. You have to keep going when it looks like you’re never
going to find anything; you have to keep looking, because it’s then
that the animals are telling you something that you don’t know. You
learn the most when you can’t find them for a long time. When you
find them right away you don’t learn as much.
Mongabay: So on that note, is there anything you can learn about the
greater ecology of an ecosystem from the presence or absence of these
Jim Sanderson: These small predators occupy a wide variety of
habitat. There’s no arboreal canine (dog) but there are arboreal cats—
cats that live mostly in trees. So as a result we have a lot more cat
species than we can have dog species. Cats show greater variation in
body weight — there’s no dog as big as a tiger — and they use space
more efficiently. Some having these small cats in an ecosystem can
tell you a lot.
For instance, one of the cats we were studying is the margay in
Brazil. We found it during the day looking around in the tops of
trees during the day. What was is doing? It couldn’t catch birds
during the day, because birds you know can out-compete a cat in the
tops of the trees. But it turns out the cat was eating bats. It was
looking for bats that were roosting in the trees. So, that tells us a
lot about the environment. When they are active during the night,
they are out hunting rodents. When they are active during the day,
they’re hunting something else. They tell us with their very presence
that there is a lot of prey out there. The health of the ecosystem
can be determined by top predators, because their presence tells us
that there is adequate prey for them.
Mongabay: Let’s look at the human element in this picture. With the
caveat that threats to cats are highly variable depending on where
they are, what are some of the greatest dangers to small cats?
Jim Sanderson: Of course some of the cats share similar threats —
like habitat destruction, loss of prey, and hunting — but they also
face widely variable threats in some cases.
The Andean cat faces three principle threats. Number one, it shows no
fear of people. So, that’s a problem when local people attribute
supernatural powers to the cat and kill it (number two). Number
three, the locals eat the same prey that the cat does, the small
mountain vizcacha that look like rabbits. So, how do we deal with
these threats? Well, the people have been hunting vizcachas for
thousands of years, so it’s unlikely they are going to change their
behavior just because we tell them the cat needs to be conserved.
What about teaching these cats to be afraid of people? Well, I have
seen four in my life, and that’s two more than anybody else that we
know about. Of the 45 people involved in this project across the full
cat range—Peru, Argentina, Chile, and Bolivia—only 6 have seen an
Andean cat alive and they have been working on this project for four
years. So, it’s not like you see this thing everyday. But that’s the
threat that we have with the Andean cat, we are dealing with some
very thorny issues here. People eat the same food and then they kill
the cat when they see it. They chase after the cat, throw there coat
over it and they just kill. So that would be a more or less direct
threat from humans.
On the other hand, a small cat called the flat-headed cat, faces the
exact opposite kind of threat. It’s does compete with people for
food. It doesn’t eat chickens. It is a lowland specialist that eats
only fish and frogs and is about the size of a small house cat. It
lives in the swampy wetlands of Malaysia, Sumatra, and Borneo. But
here the threat is palm oil plantations — the unmitigated conversion
and total loss of habitat driven by oil palm plantations. Without
regard to any of the wildlife, all the trees are cut down and then
palm oil trees are planted. And it is unmitigated, that is, there is
nothing set aside to compensate for the loss of the land. Here the
cat just loses its habitat without anybody caring about what happens.
This is the biggest threat in South Asia is the replacement of
habitat by oil palm. You can drive for hours at a time—five hours—and
see nothing but oil palm.
Mongabay: Does anyone know the habitat requirements of the flat-
headed cat? If you were to preserve riparian zones within oil palm
plantations, would that be enough for it?
Jim Sanderson: Well that is a good question—we don’t really know. But
generally there are three animals in oil palm plantations: there are
rats, palm civets, and leopard cats that eat the rats. That’s about
They are not wealthy in terms of biodiversity. I don’t think
preserving a riparian area in the oil palm would work and the reason
is that the pesticide use and what goes into those streams would just
clean out the fish and the frogs. But we don’t really know because
nobody has ever studied the flat-headed cat.
We do know that the flat-headed cat is the most aquatic of the cats.
It puts its head under water and looks for fish. When is sees prey,
it goes right into the water. It typically fishes along the river
Let me give you an example of how rare it is. If you put a camera
trap out in the mountains of Sumatra you will record all five cats:
tiger, clouded leopard, marbled cat, golden cat, and leopard cats. If
you put your camera traps out in the lowlands, you are very unlikely
to get a flat-headed cat or a fishing cat. I know of only one fishing
cat camera trap picture in hundreds of thousands of camera trap
pictures taken in Sumatra and I only know of three flat-headed cat
pictures. These are extremely rare cats. The reason is the fishing
cat and the flat-headed cat are both fish specialists and tied to
water and the lowlands of Sumatra are being converted into oil palm
plantations. So these small cats are in big trouble. We say that the
big cats act as an umbrella species, that means that if we protect
the tigers habitat and we work on the tiger and conserve tigers that
they will serve as an umbrella species to protect the habitat that
they live in. But the tigers are able to live in fairly high-density
human situations. In India these parks are surrounded by people and
we still have tigers. But when it comes to small cats, we are looking
for them and we can’t find them. Are they really under the wing of
the protected species or have they disappeared? We don’t know.
Mongabay: What can people do at home to help protect their small cats
or wild cats?
Jim Sanderson: A more environmentally-friendly palm oil industry
would be a great start. That would go a long way towards helping the
cats of Southeast Asia which is, by the way, is a hot spot for
conservation activity right now. Working in South America is a
paradise compared to working in Southeast Asia.
Increasing your awareness of these small cats is also important.
Mongabay: What about your organization?
Jim Sanderson: The site is a good way to learn what we’re working on.
A lot of focus has always been on the most endangered ones. My
priorities are covered by the red list –these are always the rarest
and least known ones: the Andean cat; the flat-headed cat; the bay
cat which is endemic to Borneo; and the Guigna. My priority has
always been the rarest ones and the ones that have largely been
Most American Zoological Association (AZA) zoos do not exhibit small
cats because they do not believe the public wants to see them. They
instead exhibit the large and charismatic small cats.
When you visit a zoo ask to see something unusual — the small wld
cats. Conservation efforts for small cats do not cost nearly as much
money as do big cat efforts. We learned to achieve a lot for a
little. Any contribution helps. See the WCN website to help out the
small cats with a tax free donation.
Mongabay: What about the Tibetan Cat?
Jim Sanderson: Very little was known about the Chinese Mountain. The
habitat was not surveyed and we didn’t have any pictures of it in the
wild. So when we set out to learn more about them, it was really hard
to find information. After a long time we finally got on the trail.
We finally were able to get pictures of it.
What was the threat to the Chinese Mountain Cat? People where making
accoutrements from the cat skins. They would kill the cat and make a
hat out of it or sell it to the Chinese Muslim traders. They’re the
ones that have the shops that sell all the animal skins.
So that was the threat — direct killing. There is no other threat;
the habitat is so huge that in the Tibetan plateau that habitat loss
is not a threat. It is mostly used for grazing. But you have semi-
nomadic herders who can’t read or write and don’t have a whole lot to
do during the day when their livestock grazing. When they see that
cats they catch them and skin them out.
One person eliminated that threat across all Tibet — the Dali Lama.
When he said, “I am tired of my people killing animals and wearing
animal skins” people across all Tibet listened and stopped killing
the cats and everything else as far as we can tell. I wish I had that
kind of pull.
This was just part of a longer statement that involved other issues,
but of course this is a very political issue. So of course when the
Tibetans started burning the skins the Chinese cracked down on them
for political actions — following the word of the Dali Lama. Even
though it was a positive thing for conservation, it was a very
politically charged time because people were listening to the Dali
Mongabay: Is domestication or keeping wild cats as pets much of a
Jim Sanderson: It is not a common thing that you see these cats as
pets — they don’t make good pets. People put out food for Guignas
sometimes, so the cats will come to get food but they don’t come
indoors of course. They shy away from people. But generally speaking
I don’t see that this is a big problem. In response to wildlife laws
and state laws people are trying to cross wild cats with domestic
cats to create crosses so they will have a more exotic house cats but
usually they escape, of course.
Mongabay: What are some other small cats that are at risk?
Jim Sanderson: I am on the IUCN cat specialist group as a voting
member. I see myself as representing the small cats and offsetting
many of the other members who are large cat specialists and are well-
represented on our group. Of course we are all colleagues and we all
help each other, but when there are small cat questions, they look to
On the opposite end from the forest cats is the sand cat, a desert
specialist. It is a little cat which lives in the northern Sahara
desert and in the Middle East. It feeds on rodents and lives in
burrows excavated by other animals because cats are not excavators.
This is another cat that lacks real analysis. We don’t know what is
happening to it. It is slipping through the cracks. I think there is
one study on it now in Saudi Arabia.
The black-footed cat is found in South Africa. It is so small it
called the anthill tiger. It is a cat half the size of your house cat
but it stands on the top of ant hills and screams.
The marbled cat is another cat from Southeast Asia and south Asia. We
believe is an arboreal specialist because of its big tail. It is much
rarer than a clouded leopard, which we know a little bit about thanks
to the work of Andy Hearn and Jo Ross in Danum Valley [An interview
with Andrew and Jo in Borneo].
I have good people working on all of these now. Those are the people
that are really doing the real work. I am just their assistant now.
Mongabay: It sounds like you have had some positive experiences
working with industry in conservation efforts. Can you talk about the
role that industry can play in protecting important wildlife areas.
Jim Sanderson: Yes, definitely. Right now I’m working at BHP
Billiton’s bauxite mine site in the Bakhuys mountains. They are going
to remove the tops of mountains to get to the bauxite, which is used
in the production of aluminum, but it is a long-range project: twenty-
five years at a single site of a couple of thousand hectares. Their
concession covers around 240,000 hectares and they control access to
the whole area. No one goes in or out the gate and into this huge
area without their permission. Workers are prohibited from hunting or
harming wildlife in any way. This means the animals there are very
It was a similar case at Collahuasi mine in Chile. This is one of the
largest open-pit copper mines in the world but the wildlife was again
protected because the workers’ behavior at the site was very tightly
controlled. They were either living at the hotel or bused back and
forth from the mine site and there was a gate to get in. So you
couldn’t access the site unless they wanted you to get in and they
restricted access to the public. So these mines that I’ve seen can be
particularly good stewards.
I always tell people that if run properly, these sites can be better
protected than a national park because in a national park the public
is allowed. In these areas no one is allowed except the workers and
their behavior is tightly controlled and monitored. So it is pretty
easy for me to see a partnership between industry and the
conservationists. I think it’s great. In addition, they have money to
support research projects. So if people are interested in studying
the wildlife or monitoring the wildlife, oftentimes they are more
than happy to provide funding for that because they like to see
people out walking around on their land where they are doing work and
writing about it.
Mongabay: Do the results of research impact whether a company
develops an area of not?
Jim Sanderson: Absolutely. In the case of Suriname, when researchers
found a small fish that was endemic to a small stream, the mining
company said, “Well, we will leave the bauxite in the ground. We are
not interested in mining there.” A finding like this gives
conservationists the upper hand.
Mongabay: What about when the miners leave? These are long-term
projects but someday these companies are going to pull out when
they’ve extracted all the minerals. So then is there kind of a risk
that these roads will then serve as conduits for development, like
logging or things of that nature. Do you have any thoughts on that?
Jim Sanderson: That can happen, but we have plenty of time to act in
between since these are long-term projects. First of all the
companies have to repair the damage that they do. When they remove
the top soil and the plants and trees, they have people there who
document everything so they area can be restored as well as possible.
The plants are put in greenhouses while mining is being conducted.
In the Bakhuys, BHP Billiton is already looking for another company
to handle the restoration even though they haven’t started
operations. They will be able to restore some of the sites where they
did the exploration. In the 20-40 year interim before they leave the
site we hope education can kick in and start to change the perception
wildlife is only food for the pot or to sell, particularly to foreign
workers. We’ve got time to look into the future and say, “We had
better start teaching wildlife classes in schools to educate people.”
Hopefully the standard of living in the country will increase during
that time as well. As standards of living rise, the need to hunt
declines. In developed countries most people who hunt do so
recreationally. In poor countries people need to hunt for food or to
sell meat to the market. They don’t have licenses, they do have
hunting seasons but nobody obeys them. In the US you can go to the
store and buy beef cheaper than you can go out and hunt a deer,
although this wasn’t the case in the early 1900s when the total deer
population was estimated to be less than 100,000 animals. That is
about the time we started getting conservation rules put into place
during Theodore Roosevelt’s presidency. So we went through a period
in the US where we nearly eliminated all of our wildlife and it seems
like other countries are learning the lesson that we learned.
Mongabay: Getting back a little bit to the mining, how does damage
from bauxite mining compare to damage from gold mining? It seems that
mercury is a big problem with small-scale gold mining here in
Jim Sanderson: It doesn’t have to be that these mines are so
dangerous. It is just the attitude of the company whether they are
going to be responsible for the damage that they do. All mining
causes damage. In bauxite mining they have to remove the forest and
the soil to get to the bauxite deposits so it is incredibly damaging.
It depends on how the company operates; whether they want to be good
stewards of the environment or whether they don’t care. Now often
times the rules of the country are so loose that the companies are
able to be whatever they want. It is only a company that shows
responsibility that says, “We are going to work in accordance with
rules that are stressed by the World Bank and not the countries
themselves because their rules are too weak.”
Mongabay: Let’s look at your current work in the Bakhuys. Are you
establishing a baseline to see how mining affects the wildlife and
Jim Sanderson: I am working at the Bakhuys mountains, which are west
of the Central Suriname Nature Reserve. This is an area that as far
as we can tell has not seen people for at least 50 years. No one
lives near it and no one lives in it. There are two small tourist
operations near by, but that is it. BHP Billiton has been exploring
for bauxite deposits there for about four years and in order to do
that exploration they put in some dirt roads. The whole area is about
520,000 acres. The bauxite deposits are relatively localized on the
tops of mountains. They are interested the highest grade ore deposits
and these are few and far between. These deposits are only several
thousand acres each and there are less than eight. They are also
interested in exploring other parts but they haven’t done that yet.
They will probably do that in the future.
What I wanted to do was establish a baseline of what was there as
part of the environmental impact statement. Three years ago I started
working on the environmental assessment of the area; focusing on the
large mammals. I decided to use camera traps as part of the effort to
establish a baseline of what lives in the forest.
The camera traps revealed the richness of the area. The pictures
started circulating around the company and they asked me if I would
continue with the monitoring project to see what kind of an impact
the mining was having. They wanted to see if we could turn the
monitoring into a way to mitigate the impact of mountain top removal
on the large mammals. So we kept on camera trapping and established a
disturbance gradient to measure how mining activities would affect
We have been doing this now for three years and still have another
two years before mining is expected to begin. So we will have five
years of baseline data before the mine ever gets really going. The
trapping has revealed a lot about the animals and we know that if we
keep running the camera traps we will eventually get pictures of all
the species. Establishing the gradient before the mining starts
allows us to understand the background and what factors — like
rainfall and temperature — affect the background. It turns out that
after three years we can pretty much say that there is no difference
between any of the sites. It’s true that only one or two sites show
the very rare animals, but more common animals such as jaguar or
pumas show up at every site — we don’t have a single site that
doesn’t have jaguars or pumas. Once mining does we will be able to
measure the impact on wildlife.
Mongabay: Expanding on camera trapping in general, because you have
an amazing amount of data, but if you could explain what you can
learn from camera trapping as far as activity times and predator-prey
Jim Sanderson: One of more obvious that we get from camera trapping
is activity patterns. We can look at the time the picture was taking
and plot the number of pictures that were taken each hour. If a
species is taken more than one time in an hour we only count that as
one picture for that for that species for each camera trap. In other
words, if an animal sits in front of the camera trap for ten minutes
we don’t want to count ten pictures, we just want to count one
picture. So we get at most one picture per hour per species per
camera, and we make a plot of this.
If an animal is active just during the day then we will only get
pictures during the day and we won’t get any at night. This makes it
possible to establish an activity pattern for each animal. For
instance from 800 pictures of tapir we know that tapir are mostly
active at night.
This is one of the obvious pieces of information that we can get from
camera trapping. When mining starts we will be able to see if the
animal’s activity pattern change.
Another piece of information that we can get is the distribution of
animals. If you work with camera traps long enough you should be able
to say ‘this camera has a lot more picture than this camera and there
must be a reason for it’. As it turns out we don’t see much of a
difference across any of our sites.
Another valuable piece of information is density, the number of
individuals in the area. To determine this we need to have two
opposing camera traps at each site and when the animal walks between
the cameras, the camera takes a picture of both sides of the animal.
For animals that are laterally asymmetric, like the jaguar which has
different patterns on each side of its body, we can distinguish
between individuals and can determine how many jaguar are using our
study area. With the proper assumptions, we can calculate how many
individuals are in a particular area and determine the number of
females and the number of male. It turns out that these jaguars are
occurring at multiple sites, so they are roaming around — both the
males and females.
When you put all this together, there are a couple pieces of
information that can be used to monitor the impact of mining.
Mongabay: You’ve also captured some interesting behavior on camera.
Jim Sanderson: Thank you for reminding me. Of course, the camera
captures also their behavior: we have pictures of jaguars carrying
armadillos in their mouths, and we have a picture of a puma wrestling
a red brocket deer to the ground. So, we get some indication of what
these predators are eating. But we also get mating behavior. We have
repeated pictures of jaguars copulating right in front of the camera
traps. All of these mating-jaguar pictures are taken in May and June,
which turns out to be near the end of the long rainy season. So we
suspect that it’s not true that these animals breed all year long,
but in fact they breed at a certain time of year in response to
rainfall, and have their young several months later during the dry
season. They leave their parents in about a year, because we see the
young in the camera traps following the mother around, and in about a
year we see the young on their own in the camera traps. So, we are
getting a little bit of a family history among the jaguars. But
definitely they are not breeding all year long as near as we can
Mongabay: Do you have any thoughts on digital versus film, what do
you prefer for camera trapping?
Jim Sanderson: One of the things first that I would like to stress is
that anybody, probably even a chimpanzee, can put a camera on a tree.
That’s not what I do; that’s not my job. My job is to put the animal
in front of the camera. So, that’s a different task than putting a
camera on a tree, and it involves many considerations.
As for using digital cameras versus film cameras: I prefer film
cameras. Now most people want instant gratification, so they want to
walk out to the camera, turn it on, and see what they have. I prefer
film cameras because they are faster.
The latency time is the time between the sensor recognizing something
has walked in front of it and the camera takes a picture. For a film
camera the latency time is about half a second, certainly, at most,
less than a second; whereas in digital cameras it’s about two-and-a-
half seconds. So with digital cameras, if you’re not careful you can
get a lot of pictures of “headless jaguars” or just the rear of
animals, because of the delay after they walk in front of the camera
sensor. The digital camera has to wake-up, turn on, and then it snaps
the picture. With the film camera’s latency time of less than a
second, you get a picture right off the bat, as soon as the sensor
picks it up, and it always appears that the animal is right in front
of the camera. But of course the instant gratification is not there —
you have to wait to develop the film. There are pros and cons.
Digital cameras suffer a little bit less from moisture damage. Power
requirements are higher for digital cameras than they are for film
cameras but the digital cameras can hold a lot more pictures than
film cameras, because a film roll is thirty-six pictures. In our test
site we can go through thirty-six pictures in a week; we have to
check film cameras more often than digital cameras. They cost about
the same as a high quality camera but that comparison is deceiving.
The question that most troubles me is when someone says ‘well, I
compared these cameras and one is cheaper than the other’. People
should know that with camera traps you get what you paid for. If the
objective is to save money than don’t buy a camera trap at all,
because they are very expensive. If the objective is to get lots of
pictures then I suggest that people buy a good camera. The metric is
the not the number of pictures but the number of useable pictures. If
you want the cheapest camera, then that’s a different metric.
Dr. Jim Sanderson is involved with the Wildlife Conservation Network,
the Small Cat Conservation Alliance, IUCN Cat Specialist Group, the
Small Wild Cat Endowment Fund, and the Feline Conservation
Special thanks to Tiffany Roufs for her help transcribing the