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The Square

So you probably know by now that season 10 is up and running and there have been some amazing camera-trap images uncovered already. As well as a few lounging lions and wandering wildebeest there have been some stunning aardvark and wildcat images.

This season has turned up quite a few images with a central square that is brighter than the rest of the frame with a luminous look. These somewhat Warholesque images look as though they have been photo-shopped and I love them. Here are just a few. My favourite is the zebra, its perfect.

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Warthog backside

 

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Tree with Landrover

 

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Zebra

 

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cheetah

 

Obviously these are not some new form of art but have a more down to earth source; a malfunction with one of the camera trap types. A patch provided by the manufacturer restores the image to normal which for scientific purposes is very good but from the purely aesthetic side its kind of sad, I like “The Square”

 

 

Grant’s Verses Thomson’s Gazelle

 

The Zooniverse team are super busy at the moment but hopefully very soon season 10 will be loaded and we can all get cracking with what promises to be a fantastic season full of amazing images.

In the meantime I thought I would post a few notes on those tricky animal pairings that seem to have more than a few people stumped when trying to id them.

To kick it off we will look at Grant’s gazelle and Thomson’s gazelle. If you were treated to perfect photos every time I think you would get the hang of these two pretty quick but with the often blurry or distant images we get on snapshot they can be tricky.

 

Grant’s gazelle A                        Thomson’s gazelle A

 

A; First off there is the overall colouration. Thomson’s has a thick dark stripe across its side, Grant’s usually lacks this but be aware as some Grant’s have a dark stripe too. Not the best distinguishing feature as there can be quite a bit of colour variation.

 

Grant’s gazelle B                          Thomson’s gazelle B

 

B; A better distinction is the facial markings. Grant’s gazelle has a thick black stripe running along the side of the face from the nose passing through the eye to the base of the horns giving a masked look. Thomson’s has the same stripe but it ends at the eye, not passing through. The white band on top of the black stripe is more distinct on Grant’s.

 

Grant’s gazelle C                                  Thomson’s gazelle C

 

C; If you get a back-side shot then Grant’s displays a much whiter overall appearance with the white area extending past the root of the tail up onto the back. In Thomson’s the white area stops at the root of the tail. Grant’s tail is white at the root and thin with whispy black end, Thomson’s is dark and fluffy looking. The black vertical bands in Grant’s are also more prominent.

 

Grant’s and Thomson’s Gazelle

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Photo NH53, Flickr (https://creativecommons.org/licenses/by/2.0/)              

In a mixed group the smaller size of Thomson’s is evident, although with young animals it is not so obvious.  Here you can easily see most of the features discussed above with the Grant’s gazelle comprising the 7 animals to the right back and the Thomson’s gazelle to the left forward. Note the Grant’s gazelle side on at the back, it shows a much darker side stripe than the others more a kin to Thomson’s. Males and females of both antelope have horns with the females usually shorter and thinner. In some females horns are absent. In general Grant’s are more graceful looking than the stocky Thomson’s.

 

 

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.

Black and White

 

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Grants Gazell

This past week I have been trudging up and down boggy slopes with armfuls of tree protection tubes, posts, tools and finally trees as part of a reforestation project in the Lake District National park, UK. With storm Doris fast approaching it has been a miserable week and my mind has often wandered over to snapshot Serengeti for some light relief.

 

The job I am doing, trying to help mitigate the over grazing of sheep and deer made me think of Michael Andersons work that has provided us with the images for season 9.5. He has written here about the project to study how herbivores affect vegetation patterns and you will have seen the enclosures around his experimental plots.

 

Some people have found that the images from this season are not quite as good as in previous seasons, they seem to be a bit fuzzy in places and there are a few less lions. On reflection though it does seem to be producing a lot of my favourite images, those taken during dusk and dawn when the camera is not quite sure if it is day or night and ends up taking a black and white daytime shot. These pictures can be quite exquisite and have the feel of being completely composed by a top photographer rather than just a random event.

 

Here are some of my favourites.

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Zebra/Wildebeest

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Impala

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Wildebeest

 

 

It is a good reminder to us all that although we are all waiting to discover that one truly great animal capture and it is gratifying to classify the more unusual beasts the aim of the whole project is science. Back in the old days of Serengetilive the classifying was done one camera roll at a time. Sometimes I would sit and classify 2000 capture events of….. grass. Seriously, you would be luck to maybe get a passing bird but it had to be gone through just in case the last couple of shots were of lion. At least with Snapshot Serengeti the pictures are randomised so you get shots from a mixture of cameras rather than being stuck on a tedious one.

 

Snapshot Rhinos

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One of the animals that continue to be a rarity on snapshot Serengeti is the rhino. We have had a handful of capture events over the years.

There are two species of rhino found in Africa; the white or square lipped and the black or hook lipped. The Serengeti is home to the latter. It is a large bulky mammal and as such many a hopeful #Rhino has turned out to be a blurry image of an elephant or buffalo.  Things can get confusing with some of the images but isn’t that half the challenge trying to guess those indescribable blobs? Surely it wouldn’t be the same if everything was easy to id?

Anyway back to Serengeti rhinos.

Just 50 years ago between 500 and 700 Eastern Black Rhino (Diceros bicornis michaeli) roamed the Serengeti-Mara ecosystem but during the seventies the population was decimated by poaching to around 10 or so individuals.

A huge effort is being made by various conservation and government bodies with enormous donations by private individuals to save the population from total extinction. Notably a remnant population in the park was highly protected and slowly, over the next few decades the population made some recovery. In 2010 it was decided that the Serengeti area was being protected well enough to try and bolster the resident rhinos with new genetic stock. It just so happened that a private owner in South Africa had a breeding herd of Eastern black rhino that had been part of the attempt to safe guard the subspecies back in the 60’s, these animals had originated from Kenya. With strict controls by IUCN officials it was deemed these animals were of the right genetic stock to be reintroduced to the Serengeti.

The plan was to translocate 32 rhinos over the next few years and release them in a new site close enough to allow some overlap with the resident 30 or so rhino. Unfortunately the project has been affected by the recent escalation in rhino poaching and it is difficult to find how many rhino have been successfully translocated to date let alone the current Serengeti total population but you can bet it is still small. The IUCN red data list states Tanzania as having 88 Eastern Black Rhino in 2011.

If you are lucky enough to stumble across a rhino capture on Snapshot Serengeti you should definitely celebrate … and don’t forget to # it.

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.

 

Why we do it

Congratulations, your time classifying images on Snapshot Serengeti has resulted in yet another scientific paper. Over 70,000 of you have contributed to analysing the millions of images produced by the 225 Snapshot Serengeti cameras over the last few years. Thanks to all your effort the cameras are still rolling, creating one of the longest running cameratrap studies going.  This data set is so important to scientists because of the size of the area it covers as well as the length of time it has been recording for. It allows them to ask many and varied questions about a naturally functioning healthy ecosystem and in today’s changing world it has never been so important to figure out what makes this planet tick.

The paper ‘The spatial distribution of African Savannah herbivores: species associations and habitat occupancy in a landscape context’ was published last year in Philosophical Transactions B. Visit here to read the article.

http://rstb.royalsocietypublishing.org/content/371/1703/20150314

The Snapshot Serengeti team argue that if we want to predict the impact of changes/ losses of large mammals in the future we need to have a quantitative understanding of a currently functioning ecosystem. It just so happens that the Snapshot data set is perfect for this. The Serengeti National Park is representative of the grass dominated Savannahs of East Africa which are home to the world’s greatest diversity of ungulate (hoofed animals) grazers.

The team present a neat graphic that shows how the various elements interact to affect herbivore habitat occupancy.

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Predators, herbivores, termites, fire, grasses and trees all play a role in determining where different herbivores choose to roam.

It seems that herbivore body size is also important to habitat selection. For example large herbivores survive by bulk grazing whereas small herbivores concentrate on grazing quality over quantity. Recently burned ground results in new vegetation growth. This growth is relatively high in nutrients compared with unburned patches and the same can be found on and around termite mounds. Small herbivores were found to occupy these areas but the sparse coverage does not favour large herbivores that must eat more volume.

The paper highlights the complex relationship between predators, herbivores, vegetation and disturbance and is well worth a read. Next time you are classifying images see if you agree. Do you see many herds of zebra or wildebeest on burnt areas or is it mostly Thompson’s gazelle? It’s another way to look at the images you classify.

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.

Reintroducing the Wild Dog

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Snack Time

One of the neat carnivores I got to work with in South Africa that we don’t experience much in Tanzania is the African wild (or “painted”) dog. These endangered carnivores live and hunt in highly social packs which, like wolves, are dominated by an alpha male and female. African wild dogs used to roam the Serengeti, but vanished in the park in the early 1990s due in part to diseases such as rabies and canine distemper contracted from domestic dogs.

During my first field season, I was fortunate enough to watch a pack of these animals being re-introduced into the park, and several more releases have taken place since. In total, over 60 wild dogs are now recolonizing Serengeti — we haven’t seen any in our camera trap areas yet, but there are rumors that they might be wandering through soon!