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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!

 

Snapshot Serengeti’s “Lost Season”

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Over the last few years, you’ve helped us identify almost 2 million photos (since there are often multiple frames per “subject”, that’s actually about 5.5 million individual frames!). And you might remember that a few months ago the first 1.2 million of those were just made available to researchers everywhere. But along the way, a few (thousand) photos fell through the cracks for one reason or another.  Some sites didn’t get uploaded because of a quirk in the file structure. Some SD cards were corrupted and only months later the brilliant UMN IT department was able to recover the photos. Whatever the reason, we’ve accumulated 16,780 capture events that we’ve called “The lost season” — and we’ve added those images to the site today!

It’s a bit of a blast from the past — most of the images were taken in Seasons 3 and 4. But they’ve never been seen before…so go check it out! Who knows what you’ll find!

Notes from the field

Note: Meredith wrote this blog post, but is having internet problems in Africa, so I am posting it on her behalf.


Pole sana on the lack of recent field updates – it’s been a busy week or two and I’ve traveled halfway across Africa in the meanwhile! Sad to say, I’ve left Serengeti behind for now. I was able to set up almost all of the replacement cameras I brought down with me and completed three new rounds for my playback experiments. I then took a few days off and spent my birthday traveling around in Ethiopia, soaking in some history and culture (and eating really excellent food!). It’s nice to have a break from constant science every once in a while. I went around what is known as the “Northern Circuit” and visited the four historic cities of Gondar, Lalibella, Aksum, and Bahir Dar. I got to visit island monasteries, rock-hewn churches, the palace of the Queen of Sheba, and even made a trip to the church purported to be where the True Ark of the Covenant is kept! Have to say, the trip made me feel very “Indiana Jones”, right up until the point where I got ill from drinking the water…

After a week in Ethiopia, I flew down to Johannesburg, South Africa, to meet up with Craig and another graduate student we’re working with, Natalia. Natalia is interested in cognition and has been testing the creative problem solving and impulse control of different kinds of carnivores. We’ve spent the last few days at a reserve outside of Pretoria called Dinokeng, run by Kevin “the Lion Whisperer” Richardson. Kevin maintains a park with dozens of semi-captive lions, leopards, and hyenas which Natalia can work with for her intelligence experiments. While Natalia has been busy with her research, I’ve been putting together a rig that will enable me to examine herbivore responses to four predator species: cheetah, wild dog, lion, and hyena. Two of these predators (lion and cheetah) hunt by sneaking up on their prey, whereas the others (wild dog and hyena) rely on endurance to run prey down. I’m looking to see whether prey respond to each species of predator differently, or whether there are consistent differences in anti-predatory response by predator hunting type. I’ll be simulating predator encounters because it would be incredibly difficult to observe a sufficient number of actual encounters in the wild. As soon as I find a good internet connection, I’ll post pictures of just exactly how I plan on doing this — it’s pretty great, and I don’t want to ruin the surprise!

Just this morning, the three of us packed up all of our gear and took a small plane out of Pretoria up to South Africa’s Northern Cape province. We’ll be spending the next three to four weeks up here in the Kalahari conducting our experiments. In addition to looking at anti-predator responses, I’ll be helping to set up a NEW camera trap grid (perhaps Snapshot Serengeti will be joined by Kalahari Cameras sometime in the near future…?). Now that we’re back in action, more updates soon!

Serengeti Update #1

First field update! I’ve been out in Serengeti Park for just over a week now, and I’m fairly surprised to report that things are going rather swimmingly. It was certainly my smoothest travel experience from the USA to date: no plane delays (unlike last time), no missing luggage (unlike last time), no egregiously extended stay in Arusha waiting for permits (unlike last time).  To be sure, field life takes a bit of getting used to again. We’ve had spitting cobras in the bathroom, ververt monkeys breaking into my car, and little black flies are out in full force. But the Serengeti this time of year is completely worth it. Last time, my field season only encompassed the dry season, but in the current rainy period, Serengeti is a completely different place. Everything is so green it almost hurts your eyes to look at it. Up in Barafu, along the eastern edge of our camera trap grid, are herds of wildebeest, zebra, and buffalo so large you can hardly believe it. (My first time driving through a herd of buffalo several hundred strong required more courage than I’d care to admit – buffalo are big and mean and certainly warrant a healthy respect. They’ve been known to ram our field vehicles before and cause all sorts of trouble).

There’s a few projects I’m working on this year with the camera traps: first and foremost finishing up the playback experiments I began last season. Every morning for ten consecutive days, I’d head out to particular camera traps and play lion roars, simulating the short-term presence of predators in an area. We see from the camera traps that herbivores start to evacuate from these scary areas (or, “areas of artificially elevated predation risk”, to use a more scientific jargon) for not just days or hours, but periods of up to three weeks! I’m interested generally in the trade-offs that herbivores have to make between avoiding areas where predators are and still obtaining enough resources to get by. Do they only avoid areas where there’s a high chance predators will be, like lion territories, despite all the tasty forage that may be contained inside? Or is the avoidance being exhibited on a finer scale – like days to weeks, rather than months to years, like we’re seeing in this experiment? Perhaps there are some species of ungulates that don’t try and avoid predators on a spatial scale at all, but rather rely heavily on evasive and defensive behaviors when they encounter a hungry carnivore. Hopefully these continued experiments and the Snapshot data in general will help elucidate answers to some of these questions!

speakers for playback setup

speakers for playback setup

I’m also working on another round of habitat characterization – this time, we’re interested in the soils and vegetation that help to determine the forage quality at a particular site. Now, to tell the truth, I wasn’t originally that enthused about these particular collection tasks, but I’ve discovered that there’s incredibly satisfying about grubbing around in the mud scraping out soil samples. My inner 8-year old is feeling more rejuvenated by the day. Lion House is started to become more than a little cluttered with sample bags of dirt and grass clippings – pole sana, other field assistants, it’s for Science!

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bookshelf-turned-soil collection storage area

 

 

Season 8 Movie Time

Looks like everyone is sinking their teeth into Season 8! As a reminder, feel free to ask questions or chat with us through the Snapshot Serengeti Discussion board or in the comments of any of our blog posts.

Now, there’s some data from this new season that hasn’t made it online — sometimes, instead of taking pictures, our cameras accidentally switch into “video” mode and capture 10-second clips of animals doing their Serengeti thing. While this isn’t very good for us in terms of data collection (although we’ve been tossing around the idea of setting up a Snapshot Serengeti: Video Edition!…), it gives you a unique perspective on the lives of these animals.

(Okay, so it’s mostly animals eating grass. They eat a lot of grass. Perhaps not the most “unique” insight on their behaviors, but they’re still pretty fun to watch). Here’s some of my favorite accidental movies from our new Season!

[youtube http://youtu.be/R0N24gZvfRg%5D [youtube http://youtu.be/4GyEEbCa9pM%5D [youtube http://youtu.be/vR6A9gDmhd0%5D [youtube http://youtu.be/po1WTdJPc20%5D [youtube http://youtu.be/TWPWruyWb94%5D [youtube http://youtu.be/ZUSJOyPvlZk%5D

 

(If you want more videos, Margaret has blogged some of her favorite movie clips from past seasons here and here)