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Happy Birthday To Us

Camera-trap

 

Snapshot Serengeti has around 225 camera-traps laid out in a grid in the heart of the Serengeti National Park. They have been there for around 7 years and make up one of the longest running camera-trap monitoring projects in the world. Snapshot was launched on the Zooniverse portal in December 2012 and has inspired many more similar camera-trap projects from around the world. So Happy 5th Birthday to us, may there be many more to come.

There is no doubt that camera-trapping has gripped the hearts and imagination of both scientists and the public. Eight years ago when I first used camera-traps I had to explain them very carefully to friends and family as they had never encountered them, these days references to camera-traps appear in popular press articles and  wildlife documentaries and most people have a basic idea of their use in conservation.

It was K. Ullas Karanth, an Indian wildlife zoologist, who is credited with pioneering the use of camera-traps as scientific tools in his study of tigers in the 1990’s. In the last two decades the technique has advanced at a hugely fast pace and has revolutionised the study of elusive and seemingly well known species alike. It is a scientists dream to observe animals without being present yourself to influence their behaviour.

But looking at the history of the discipline I can across many references to much earlier work using camera-traps. Back in 1927 National Geographic published an article by Frank M Chapman titled delightfully “Who Treads Our Trails”. The piece opens with this amazing paragraph

“If there be any sport in which the joys of anticipation are more prolonged, the pleasures of realisation more enduring, than that of camera trapping in the Tropics I have yet to find it!”

This guy would have loved Snapshot Serengeti. This is most likely the very first scientific paper to report on using camera-traps all be it very different cameras. His rig involved a tripwire the animal steps on rigged up to the camera shutter and bowls of magnesium that will explode and create the flash needed to illuminate the animal at night time. It seems incredible now that this would be allowed considering today’s ethically minded ethos but the author himself points out that the alternatives to studying animals could include using dogs or trappers to catch an animal or even poison bait. He decides he wants a census of the living not a record of the dead and so the idea of camera-traps for scientific study are born. He drew heavily from the work of George Shiras who published the first pictures taken by remote camera back in 1906 (also in National Geographic). George Shiras took the pictures for the pictures sake only later becoming involved with conservation but Frank Chapman was a true scientist.

Obviously the technology has changed a lot and the loud noisy explosions that accompanied Franks work have been replaced by covert black IR where even the glow of the infra-red flash is almost invisible. He would marvel at the amount of pictures that can be stored on an average SD card and that camera-traps are being used from the tropics to the snowfields of Antarctica.

You can look for the original article with this reference:

Chapman, F.M., September 1927. “Who Treads Our Trails?“, National Geographic, 52(3), 331-345

Or visit this site to see some of Frank Chapman’s images: http://www.naturespy.org/2014/03/camera-traps-science/

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Dynamic Landscape of Fear

Lions with zebra kill

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The Snapshot team have written another paper using the Snapshot data we all help to classify. The paper A ‘dynamic’ landscape of fear: prey responses to spatiotemporal variations in predation risk across the lunar cycle can be found at http://onlinelibrary.wiley.com/doi/10.1111/ele.12832/full for those of you interested in reading the original.

Lead by Meredith Palmer the paper explores how four ungulate species, buffalo, gazelle, zebra and wildebeest respond to predation risk during differing stages of the lunar cycle. These four make up the bulk of the African lion’s diet in the Serengeti along with warthog. Of course warthog are strictly diurnal so are not affected by the lunar cycle as they are tucked up nice and snug in a burrow.

For the other four night time can be a stressful time. None of these animals sleep all night, they snatch rest here and there, keep grazing and most importantly of all keep a watchful eye or ear out for possible attack.

It has long been thought that prey species territory is shaped by fear and that animals have safe areas (where they rest, give birth, etc) and risky areas where they instinctively know predators may be lurking. These areas trigger a risk versus reward response as they often contain better forage/water etc.

What Meredith and the team argue is that this landscape of fear is very much dynamic changing not only with seasons and night and day but on a very much finer scale as influenced by light availability through the moon.

Lions find it so much easier to hunt during nights where the moon gives of least light. It gives them a great advantage to stalking close to their prey using the dark as a kind of camouflage. The prey species, on the other hand, are at a distinct disadvantage, they can’t see the stalker and even if they sense its presence they are reluctant to flee as this presents a great risk in itself if they can’t see.

Meredith and her colleagues took the data from Snapshot Serengeti to quantify nocturnal behaviour of the key species using the presence or absence of relaxed behaviour (defined when we classify a species as resting or eating.) They then overlapped this with data collected through Serengeti Lion Project on lion density and hunting success. This data enabled them to work out what areas where high or low risk to the prey species. Using a clever statistical program, R, the data was analysed to see if lunar cycle had any bearing on animal behaviour, in particular, predator avoidance.

They found that moonlight significantly affected the behaviour of all four species but in a variety of ways. As we mentioned before there is often a good reason to venture into the high risk areas and the trade off in increased risk of predation is a really good feed. Buffalo for instance don’t change their use of space so much but were found to form more herds on dark nights. It seems safety in numbers works well for buffalo. Zebra react similarly in their herding activity but are much more erratic when it comes to space use, moving around a lot more randomly keeping potential predators on their toes.

Each species showed an aversion to using high risk areas at night but, particularly wildebeest and zebra, were found to increase their use of these areas when the moons luminosity was higher and safety increased. It was noted that high risk areas where avoided more frequently in the wet season than the dry. The thought being that there is increased hours of moonlight during the dry season that the animals take advantage of. Perhaps too the drive to find enough good food is a factor.

This paper serves to remind us that although what we do at Snapshot Serengeti is fun it is more than just a way for us classifiers to pass the time. It really has a very significant role in science and that role is ever increasing.

 

Antelope Versus Oxen- The Case of the Eland

 

ser eland pair

 

Of all the antelope that we classify on snapshot Serengeti the eland is one of the most distinct. Its massive size, heavy set horns and swinging dewlap lends it a bovine appearance yet it is an antelope – all be it Africa’s largest. A member of the Tragelaphini family or spiral horned antelope the eland is closely related to kudu, nyala and bushbucks.

There are two species, the common eland (Taurotragus oryx) we are familiar with in the Serengeti and the giant eland (Taurotragus derbianus) found sporadically in woodland savannah across Central and West Africa. One thing to get straight is that giant eland are on average less bulky than their common cousins, the ‘giant’ refers to their horns.

At close to a thousand kilograms in weight a fully grown male eland equipped with a fortified neck and viscous hefty horns could prove a lethal adversary. Perhaps it is unsurprising then that most male interactions are highly ritualised and the real fighting only really occurs between males of near equal stature. It is an unusual trait in male eland that the neck, shoulders and dewlap continue to enlarge as the animal ages. They develop tufts of wiry hair on their foreheads and noses and a strange clicking in their knees develops that is audible quite some distance away. I remember once sitting in a clearing in the bush and hearing what sounded like multiple people cracking their knuckles whilst moving closer towards me. I could not even begin to imagine what was fast approaching me and began to get a little nervous, looking around for a tree to climb. I heard nothing else but the odd branch moving until out from the edge of the bush appeared a small group of eland. Much to my relief it was precisely these knee clicks that I had heard.

Although not a particularly fast running antelope eland are noted to be extreme jumpers. They are capable of leaping over three meters high from a standstill which to me puts to bed any lingering doubts that they are antelope not oxen.

As many of our snapshot images attest to they are often found in quite large herds, congregations 100’s strong are not unheard of. But all the same there is no real structure to the group. Herds can comprise all males, all females or mixed sexes and ages. They are highly interchangeable and very few bonds are formed. Even the sacred mother and calf bond is tenuous in eland society. Calves form crèches when they are a few days old and prefer to hang out away from the adults. They only suckle once or so a day and that can be the only time spent with mum.  Female eland will band together in defence of their young but as they are often out of sight of the youngsters this doesn’t happen too often. Instead young eland grow fast attaining 450kg in their first year.

Young eland creche

Although life seems good in these juvenile gangs and generally eland are long lived, mortality can be high in youngsters. Whilst studying leopard in South Africa we found eland was a common prey item, in fact we discovered three kills within a month of eland less than six months old and those were just the ones we found. Lion and hyena are also known to take their toll. There is no real synchronised birthing in eland herds with young born at anytime. I guess this means there is always a slightly younger, less savvy, youngster in the crèche that is easy prey for predators.

 

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Leopard with eland kill

 

Next time you find an image of an eland herd have a close look to see if you can work out if they are females (smaller with more slender horns), males or if perhaps it is a crèche.

Citizen Science Conference

 

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Meredith giving a project slam Photo: Avi Baruch

Meredith has been busy this past week attending the Citizen Science conference in St Paul, Minnesota. She reports back that it was a fantastically stimulating conference that confirms the high esteem that citizen science has grown within the science community.

 

The yearly conference sees a diverse group of people from researchers, educators and universities to the likes of NGO’s and museums get together to discuss the use and promotion of citizen science. Although we at Snapshot Serengeti have been aware of its great impact for some time citizen science is now emerging and is recognised as a powerful tool in the advancement of research by many.

 

Those attending the four day event collaborated by sharing their varied experience and ideas on a variety of topics. The collection and sharing of data and how to impact policy was discussed. There was focus on how to use citizen science as an engaging teaching tool, how to bring citizen science to a wider audience and how to involve citizens more in research. Those attending brought their joint experience and expertise together to discuss how citizen science impact on science could be measured and evaluated. If you want to find out more about the conference then visit this link.

 

http://citizenscience.org/association/conferences/citsci2017/

 

We sometimes forget when working away at classifying our stunning images on Snapshot Serengeti that there is a lot of tech going on that enables us citizen scientists to be of use to the scientists. Meredith gave what’s known as a ‘project slam’ essentially a 5 minute presentation about our work on Snapshot Serengeti  and how it has paved the way for helping other cameratrap citizen science projects. A quick look around Zooniverse will show just how many there are now.

 

The massive amount of data produced over several seasons through Snapshot Serengeti have allowed the development of a robust, tried and tested methodology that smaller projects would have taken years longer to develop. Just contemplate the work that went into developing interfaces, protocols, pipelines and algorithms for taking millions of classifications of untrained volunteers and turning them into a dataset which has been verified to be >97% accurate.

It is awesome to see that something we all find so truly engaging can translate into such serious stuff in the field of science. I think we, the citizen scientists, and the Snapshot team can be rightly proud of our work on this brand new branch of science

Snapshots From The Past

 

This weeks guest blog is from our moderator David Bygott who has been guiding us through Snapshot Serengeti images since the beginning.

 

I’ve been lurking here for years as a moderator, but Lucy Hughes invited me to come out of the shadows and tell you how I got my Serengeti creds.

As a country boy in England I was obsessed with nature and yearned to see more of the world’s wildlife. Reading “Serengeti Shall Not Die” by Bernard Grzimek, inspired me to go there. The dream took some years to achieve. First, I worked hard to get a zoology degree. Then, I wrote to anybody doing field research in Africa who might need a research student, assistant, or slave. I got lucky. A scientist, studying hyenas and wild dogs in Ngorongoro Conservation area, wanted me to work on her better-known chimpanzee project, which I had been following in the pages of ‘National Geographic’. Sounded good.

Thus in 1969 I pitched up at the camp of my new bosses, on the floor of Ngorongoro Crater. Ten days of getting to know Jane Goodall and her photographer husband Hugo van Lawick, and total immersion in African wildlife. Incredible nights of watching hyena packs run down wildebeest and tear them apart. Even a road trip into the heart of Serengeti.

A seed sown, my mind blown, I continued across Tanzania to the remote chimp camp at Gombe National Park on the beautiful forested shore of Lake Tanganyika. Here I spent 2 amazing years with a small team of young people, following the famous chimps through the forest and recording their behavior. Experiencing at first hand our closest kin was a life-changing experience for me.

 

David with the gang
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David with a chimp group at Gombe, 1970

 

While at Gombe, I met more of my scientific heroes. Bernard Grzimek visited, so did Dian Fossey, and I travelled to Rwanda to see her gorillas. Jane’s doctoral advisor Robert Hinde came, and encouraged me to write up my fieldwork for a Cambridge PhD.

Two unexpected things happened at Cambridge. I met my wife, primatologist Jeannette Hanby. And we got to know Brian Bertram who had studied Serengeti lions for 4 years, following George Schaller’s pioneering work. Brian persuaded us that social carnivores were just as interesting as primates, and that there was still more to learn about lions. It was a change of direction, but we were tempted!

So in 1974 we joined the Serengeti Research Institute as lion biologists, thanks to support from the U of Cambridge. Our main mission was to census the lion population, as National Parks feared that lions were decreasing (they weren’t!). We also compared the lives of lions in different habitats (Serengeti Plains where prey abundance is seasonal, and Ngorongoro Crater where prey is always abundant). And we investigated lion pride dynamics – why do some individuals leave, and others stay?

Imagine being part of a community of scientists studying every aspect of the ecosystem. We had a house in the centre of Serengeti and a Land-rover to go wherever we wanted, and we spent our days and nights with the great tawny cats.

 

DB & lions & tent Feb 78
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Sometimes humans and lions are attracted to the same campsites

 

It was remote, but fortunately we were both used to that. Every month we made a supply run – either to Arusha or Nairobi, each at least 200 miles away, mostly on dirt roads. This took 2 days each way, plus several days of shopping and socializing. We learnt a lot about fixing cars, often in beautiful remote settings with primitive tools.

 

 

 There was much less technology then. We had basic maps but no GPS, radio or mobile phones or internet. There were no computers, though we had cutting-edge hand-calculators. Radio-telemetry was in its infancy; we built our own radio-collars and darted and collared a few lions, but for most of our study we had no air support and ground-to-ground range was poor, so we had to rely on careful searching to find the lions – scanning with binoculars, driving, staying out at night to listen for roars. We identified the lions from natural markings and close-up photographs, on film of course. We developed a symbiosis with cheetah biologists, George and Lory Frame, photographing each others’ study animals whenever we saw them and trading ID photos to increase our sightings. We learnt as much as we could about what all our colleagues were doing, and often participated in ecosystem-wide aerial animal censuses.

We tried various methods of counting lions, including aerial and ground transects and individual recognition. The latter proved the most successful, but it was hard work to identify all the lions in our 1000 square study area. In addition, every second month we’d spend a week in Ngorongoro Crater. After finding as many lions as we could there, we would follow one pride for 4 days and nights, to observe their activity, range and hunting success. We did the same with a comparable pride living at Sametu on the Serengeti Plain. The story of the Sametu pride unrolled like a soap opera, and we couldn’t resist writing a book about them. “Lions Share” tells their story, but also incorporates much of what we knew about lion behavior and about the ecology of Serengeti. (Out of print, but look on Amazon).

Eventually we had to leave, and our friends Craig Packer and Anne Pusey took over the Serengeti Lion Project. Craig amazingly kept it going from 1978 to 2014, and Snapshot Serengeti is an offshoot of what has become one of the world’s longest running wildlife studies.

After writing up our 4 years of lion data, we returned to Tanzania in 1982 to work in conservation education; university teaching, producing guidebooks and interpretive displays, and guiding safaris. We built our home near Lake Eyasi, and experienced years of village life and culture clash, but that’s another story (in preparation). In 2003 we moved to Tucson, Arizona, but I still get back to Tanzania every year, mostly leading National Geographic Expeditions.

I’m organizing my own safari to visit Serengeti and other parks in February 2018. If you seriously want to see these wonderful animals in the flesh, send me a message!

Field Life

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Nzunda setting up a weather station

 

 

Recently, as those of you who follow will know, I have been talking about the different people who work for the project in Tanzania. Reading about their daily lives working in ecology and conservation is about as close to visiting Africa as many of us will get. Their lives seem so fascinating I think because they are so different to most of ours (though that is a bit of an assumption of course!)

I talked to Ozward Nzunda, one of Dr Michael Andersons Tanzanian field assistants in the Serengeti. Michael’s project looks at vegetation and the interactions between herbivores and their savannah habitat. In order to study this a wealth of environmental data is needed and of course Michael, like many professors, is not based in the Serengeti. He relies on Nzunda to keep things running whilst he is not there. I asked Nzunda about his work and what it was like living in the famous Serengeti National Park.

He told me that most of his work in the field involves the collection of data from all over the study area. There are camera-traps that are checked once a month in order to down load the data and check for any maintenance issues. This is the data which we are busy classifying now on season 9.5. He must also collect weather and soil moisture data on a monthly basis in preset locations. He has to install the weather stations and soil moisture sensors and keep monitoring them until the data is collected. These jobs take up most of his time but he also has the unenviable job of keeping the project vehicles running. Tree and seedling surveys are done on a yearly basis.

So how does he manage all this and what does he think about it?

He told me that the days are long in the field, the drive to the study plots is long and so a lot of time is spent in cars and when you get to the study plots there is a chance you won’t be able to get out the car to do anything. Many a time he says, he has arrived to find lion sleeping or with a kill near his plot and is forced to wait for the lions to leave or move on to another plot. Of course so much time in the field also means he gets to enjoy seeing lots of game on a regular basis.

The study is a continuous study and that means that the data must be collected come rain or shine and in the wet season that means mud. Nzunda told me that the hardest part of the job is wet season driving when you can easily get stuck in the black cotton soils. The mobile signal is poor, as you can imagine, in the park and he has been forced to sleep in the car on occasions until help arrives the following day.

In fact he says they regularly camp out in order to visit the remoter plots and has some interesting stories to tell. Camping in an area with a full complement of wild animals is not for sissies! But on this particular occasion it was the ants that kept them awake. A swarm of biting ants invaded the campsite and had them jumping up and down, shaking out clothes and acting like mad men until they finally left. Itching and scratching they finally got to sleep only to be woken up a few hours later by a rampaging hippo careening between their two tents. Now a canvas tent is no match for a hippo but luck was on their side and the hippo kept running and didn’t return. He says he will never forget this night and they named the campsite “one eye open and one eye close” in honour of the fact no one really slept that night.

His family and friends think he is mad for working alongside wild animals, they think only of the risks but Nzunda loves the challenges field work brings and says that the Serengeti is a beautiful place to be.

Life in the field can be a little lonely. His family live almost 1000km away and he only see’s them about once a month if he is lucky. But they are all accepting of this and are happy. A good job is worth it. He prefers the park saying it is a very good place to live, far better than town where there is too much noise and pollution. He gets his fill of social once a month when he leaves the park to go on a shopping trip for supplies. The rest of the time there is a small shop that caters for the parks staff and resident researchers and the little community gets by fine.

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Nzunda checking out the mud situation.

The Data Game

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Team member checking a camera-trap

 

So we all know there are millions of images on snapshot Serengeti and that it is us citizen scientists who do all the work classifying them. The scientists can then get on with the task of figuring out what’s going on out there in the animal kingdom, hopefully in time to save some of it from our own destructive nature.

But… have you spared much thought as to how the images go from over 200 individual camera-traps dotted around the Serengeti to the Zooniverse portal  in a state for us to start our work.

Firstly the SD cards have to be collected from the cameras and as this is an ongoing study replaced with fresh SD cards. This is done about every 6 to 8 weeks. A camera traps batteries can actually go on performing far longer than this but as the field conditions can be tough you never know when a camera may malfunction. This time frame is a good balance between not ending up with months worth of gaps in the data and not spending every minute in the field changing cards.

The team are able to check about 6 to 10 sites a day so with 225 cameras in play it takes around a month just to get to each site. Mostly the cameras are snapping away happily but there are always some that have had encounters with elephants or hyena but actually some of the most destructive critters can be bugs, they like to make nests of the camera boxes. As well as checking the cameras themselves the sites need to be cleared of any interfering foliage, we all know how frustrating a stray grass blade can be.

 

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Snake camping out inside the camera-trap

 

So with a hard drive full of all the data it then has to wait for a visiting field researcher to hand carry it back to the University of Minnesota, USA. It means the data is only received every 6 months or so but it is far safer than trusting the post. Once safely received it is up to Meredith to start the painstaking work of extracting the date time stamps. As sometimes happens there are glitches and she has to fix this by figuring out when the camera went off line or when capture events got stuck together. She says it is much like detective work. The images are then assigned codes and stored on the Minnesota Supercomputer Institute (MSI) servers.

Once it is all cleaned up and backed up it is sent to the Zooniverse team who then format it for their system giving new identifiers to each image. Finally it is ready for release to all the thousands of classifiers out there to get to work on.

So as you can see it really is a team effort and a massive under taking. It is no good collecting tonnes of data if there is no one with the time to do anything with it. I will take this opportunity again to thank you for all your help with the project. Keep up the good work.

Meet the People #2

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Ingela showing camera-trap images to local Maasai

Photo: KopeLion

In my last blog I mentioned Ingela Jansson and the KopeLion project and promised to tell you more.

Ingela spent three years working for the Serengeti Lion project as a research assistant monitoring lions in the Serengeti National Park as well as the Ngorongoro Crater. Although working in the park was an amazing experience it was the work she did in the crater area that was to prove a more urgent calling. The very real conflict she saw between humans and lions persuaded her that if someone didn’t do something the Ngorongoro lions were headed towards extinction. And so KopeLion project was born in 2011.

The Ngorongoro conservation area was gazetted in 1959 and designated a multi use landscape. The pastoralist population were permitted to continue living there alongside the wildlife. Since this time the population has risen 10 fold and the once harmonious coexistence with lions has collapsed. Lions have disappeared from much of the area and the connection to the Serengeti lions is all but extinguished.

Enter KopeLion. The project aims to foster human – lion coexistence through community engagement, science and mentorship. One of the most successful outcomes so far is the recruitment of former lion hunters as lion protectors, we heard Roimen’s story last week.

But just how do you ‘engage with the community’ to try and change their minds about living with a dangerous predator. Well KopeLion do this in many ways. Firstly most of the employees are local which means they already have the community’s ear. To the Maasai their live stock are sacred so KopeLion spend a lot of time trying to reduce lion conflicts. They follow the model developed by Lion Guardians Ltd ( http://lionguardians.org )by helping local herders to build sturdy bomas,  searching for missing livestock, treating injured livestock and warning herders when lion are nearby. The lion guardians or Ilchokutis are assigned an area of between 60 and 200km2 where they monitor lions or signs of lions scientifically. They also try to prevent young warriors or Morani from carrying out lion hunts. Part of their role is as mentors to the younger generation.

The Maasai still hold strong traditional beliefs and have strong community ties, recognising and embracing this is one of the reasons for KopeLion’s success so far on its mission to help humans and lions live in peace. The strong local ties mean KopeLion have won trust amongst the local herders and in 2016 they were able to stop more than 20 lion hunts from going ahead and have seen the evidence that their efforts are working in the fact that two of the monitored lion prides now show complete survival.

Ingela and her team at KopeLion are doing such valuable work that I urge you to head over to their incredibly informative website to read more about it.

http://kopelion.org/

 

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The KopeLion team immobilizing a lion

 

Photo: KopeLion

The Challenges of Field Work

 

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Hazard of the job; catching myself on camera-trap

 

If you have clicked through the seemingly endless captures on Snapshot Serengeti then you must have realized just how many cameras are snapping away out there in the Serengeti. Have you ever wondered who looks after those cameras?

Researchers sometimes go to extreme lengths to collect their data and not much deters them from their goal.

On a recent assignment working in Central African Republic I was tasked by our biologist to collect in an array of 40 camera-traps. The park was very large, the size of Wales and very remote, the nearest village was a 12 hours 4×4 drive away. It was also newly proclaimed and had little in the way of infrastructure like roads. Of course, Thierry wanted to survey the areas we didn’t yet know so obviously the cameras were nowhere near any of the smatterings of roads.

He presented me with a mobile phone resplendent with a mapping app which showed the camera trap locations overlaid with our rudimentary road network. I should really say temporal track system as these so called roads consisted of two tire tracks driven through the elephant grass and mud soon to grow over again in the coming wet season. The park consists of a mosaic of wooded savannah and tropical lowland rainforest so you are either struggling through 2 meter high elephant grass or deeply tangled riverine forest growth. Added to the physical challenges of working in the park was the fact of it harboring armed Sudanese cattle herders, poachers and Lord’s Resistance Army militia.

So equipped with the mobile phone, two trackers and 5 armed rangers off we went to collect the cameras. After three hours bumpy ride plagued with biting tsetse fly we got as close to the first camera as any road was going to take us. Using the phone to navigate I pointed us in the general direction praying that the battery would last. If it failed we would be completely lost with no landmarks. Two kilometers later we had narrowed down the camera location to about 20 meters and under the vigilant eye of the rangers myself and the two trackers began searching for the camera in the thick jungle tangle.

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Rangers caught on camera-trap whilst on patrol 

 

Once the camera was reclaimed it was bagged up and we set out for the walk to the next camera another kilometer or so away. The whole day was spent battling foliage and insects in the 40o c temperatures for a total of 8 cameras. We made camp for the night; the journey back to base was just too far with so many cameras still to collect. It took 4 days to collect half the array and it was with some relief that we trundled back into base camp having had no encounter with armed men.  A hot shower, something other than sardines to eat and the excitement of examining the camera-trap pictures was a just reward for all our foot work

The cameras were being used to assess what species were present in the park and as such were left up for short periods in small arrays. In the Serengeti however, there are 225 camera traps permanently running in an area of 1125 km2. Just think of the logistics involved with changing batteries, keeping vegetation trimmed back and changing SD cards. Our researchers work tirelessly to keep the project on its toes and over the next few months I will try to bring you their stories about the work we support from the comfort of our homes. We each have our part to play but together we are a team dedicated to furthering a scientific cause.

 

The Secret Life of Trees

This is another guest post by Drs. Tom Morrison and Michael Anderson  about the Snapshot Serengeti Special Edition and what their research hopes to uncover.

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Seeing the forest for the trees

First, a big THANK YOU to everyone who has helped classified images at Snapshot Serengeti, both past and present. Without the continued help of this great online community, our research would come to a grinding halt! So thank you. A number of folks (and at least one giraffe) have asked about the new study currently up on Snapshot Serengeti, so here’s a fuller explanation of this work.

Photos from our newest Snapshot Serengeti Special Season come from a camera trap experiment in Serengeti involving friends and collaborators based at Wake Forest University (US), University of Georgia (US) and University of Glasgow (UK).

One of the exciting things about these new images is that they come from some of the more remote corners of the park, far beyond where past photos (Season 1-9) were (and continue to be) collected. So, keep an eye out for different species than past surveys. For instance in the north, you might see oribi, a small and elegant ungulate with a large dark scent gland below its eye. In the south, our cameras overlap the home ranges of some of the few black rhinoceros still living in the park, and we already know there are at least a few rhino images in our pile, like this:

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We set these cameras at a slightly higher height (1.5 meters in most cases), which allows us to see species from new wider angles. Admittedly, this new experimental design makes animal classifications a bit harder because we can often see far into the distance. Our advice is to simply do your best, but don’t sweat it too much if you can’t figure it out. Better to see the forest than the trees.

Back to the research…

Speaking of trees, this new study is trying to unravel the secret lives of trees. We monitor hundreds of individually marked trees around the ecosystem and revisit them each year to measure growth, survival, disease and few other things. You may have noticed little cages in some of the camera trap photos (see giraffe above). These are part of our experiment and enclose four small native tree seedlings which we transplanted to the plots after growing them in a nursery for 6 weeks. In fact we planted over 800 seedlings around the ecosystem to study the relative importance of herbivory, fire and rainfall on seedling growth and survival. So, we need camera traps to monitor things when we’re not there.

For example, check out the following sequence captured on one of our game cameras in southern Serengeti involving one of our marked trees:

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What’s amazing about this is that not only does an elephant kill an adult tree, he does it under 60 seconds. This tree is an Acacia tortilis, or the “umbrella acacia,” named for its characteristic flat top. Umbrella acacias are one of the most common trees in Serengeti and one of our main study species. Images like these help inform our study of trees, telling us how they died, or at least how many large herbivores were in the area to potentially kill and eat them. But this begs the question: if a tree falls in the Serengeti, will anyone hear it? At least we know that there’s a small chance that one of our cameras might see it.