Archive | Camera Trapping RSS for this section

A Team Effort

Snapshot Serengeti has been on the go since 2010 in one form or another and over those years a team of dedicated people has kept it running. The base of the effort is the 225 camera-traps that have been snapping away continuously for that whole period. Of course for that to happen there needs to be researchers and assistants on the ground physically looking after camera-traps, a scientific team who coordinate all data processing and analysis, a management team running the administration of the project  and generous funders to keep everything alive and kicking.

Snapshot Serengeti could also not work without all the thousands of volunteer citizen scientist who generously give their time and energy to classifying all the millions of images, ultimately helping the researchers to answer scientific questions we hope will aid in the conservation of all that we love about the Serengeti.

Here in these blogs we have celebrated all these people but it dawned on me recently that there is one group of people that seem to have been forgotten, our moderators.

Our amazing team at Snapshot Serengeti deserve a special mention. They, like our citizen scientists are volunteers, dedicating their time and expertise for free. Contrary to what some may think they are not part of the scientific team in as far as they are not university students who do the job as part of their studies. No, they are a mixed bunch in terms of back ground and do the job plain and simply because they love the Serengeti and love the project. They spend a huge amount of time online helping other users with their classifications, guiding new users through some of the pit falls they know only too well and sharing their collective knowledge through prompt responses to questions and great information posts helping others with less experience to understand the Serengeti and its wildlife. They also have to deal with the odd, luckily very infrequent, troll which is a thankless task in diplomacy. We are privileged to have such an amazing team and I know that they are greatly appreciated by Snapshot Serengeti’s participants.

So thank you to davidbygott, maricksu and tillydad who have been with us since the beginning and welcome to parsfan and nmw. You Guy’s are the best and Snapshot Serengeti would not be the experience it is without all your help.

 

50c2176d8a607540b905d32d_2

Hartebeest through a dislodged camera-trap cover.

Advertisements

Vulture Culture

Lappet-faced vulture

 

Of all the large birds out there on the Serengeti plains the vultures are probably the most recognisable, with their long barely feathered necks and large hooked beaks, you can’t miss them. For a lot of people they are ugly birds and their behaviour makes people shudder, all that frantic plunging of necks inside messy carcasses. Some cultures revere the vulture, instilling magical attributes to them whilst others vilify them.

But the truth is they are just birds with their own unique ecological niche, one that is absolutely essential to the health of the whole ecosystem.

Lets break it down. That neck, well the fact that the whole head and neck is either bare or only lightly feathered is a marvellous adaptation to keeping clean. Yep, not something people generally associate with vultures but they are in fact pretty clean birds. That beak, well it may look like it could kill quite efficiently but it is actually designed to grip hard and rip. Believe me I have been around rescued vultures and felt the effect, there is a lot of power there. A vulture will use its sizable feet to hold a tricky bit of carcase down when trying to tear off a chunk but the real power comes from the strong neck muscles and the powerful beak.

If you look closely at the different species of vulture you will notice that not only is there a difference in size of individual species but in the beak size. There is a hierarchy in vulture etiquette at a fresh carcase. If the dead animal is large and has a tough hide, say a buffalo, the larger species such as lappet-faced will be needed to ‘break in’. Their huge beaks and added bulk allow them to head straight for the good bits where lesser vultures would have to start with the natural openings such as the eyes, mouth and anus. Once the large vultures have broken in, the rabble takes over and fights it out for the good meat, the white-backed and Ruppell’s. Around the peripheries the hooded vultures will be waiting for the chance to snatch up bits of anatomy that are sent flying by over- zealous cousins or to dart in when the carcase looks almost clean to pick off the last bits of flesh in hard to reach places. It is not uncommon to see this species right inside the empty carcase and its slim lined beak is great at cleaning up.

Vultures search for food from the wing. Research has shown that in the Serengeti it is most often the lappet-faced that arrives first despite the numbers of this species being lower than the others. It seems they are extra vigilant or just have better eyes. The descent of this the largest African vulture draws in the other species who can be clued into the find from over 30kms away. It is quite breath taking to see many vultures on rapid descent with wings held inwards, feathers splayed it can also be noisy.

But other than cleaning up unsightly dead things how do vultures help the ecosystem? Like other organisms that consume dead animal matter vultures are immune to a lot of deadly diseases. Their stomachs are filled with very acidic digestive juices which can destroy diseases such as anthrax, cholera and rabies. Most scavengers would not be immune to these types of disease and what’s more, diseases such as anthrax can lay dormant for decades posing an ongoing risk. Of course vultures alone can’t keep the Serengeti disease free but with their ability to fly over 100km a day they do a darn good job of patrolling the plains and keeping them clean.

But outside of protected areas vultures are in decline. In places like South Africa there has always been a value placed on vultures with Sangoma or witchdoctors prescribing vulture heads for people needing to see into the future to answer big life questions. Of course this has modernised, now people purchase vulture heads to see the winning lottery numbers. Vultures are also targeted by poaching gangs who, in an effort not to have their poaching camps discovered, place poison bait to attract and kill the vultures. India, several years ago nearly lost ALL its Gyps vultures. 95% where thought to have died and the main cause discovered to be adverse effects from a drug called diclofenac that was widely given to domestic stock. The drug has since been banned in India but its use as a veterinary drug in Africa is rising causing major concern amongst conservationists. Loss of habitat is also an issue.

We are lucky that the Serengeti is an ecosystem functioning normally with all its facets. You may be lucky to spot, lappet-faced, white-headed, white-backed, Ruppell’s griffon, hooded and Egyptian vultures in our camera trap images. It is quite remarkable to find this type of balance these days and we thank the vultures for their ongoing services.

Recap on Snapshot

50c214228a607540b903692c_0

Snapshot Serengeti camera-trap image: Topi

Whilst stretching the corners of my brain to think about a new topic to write about in the Snapshot Serengeti blogs it astounds me to realise just how long we have been going for; over 7 years now as Snapshot Serengeti and almost 10 if you include the Serengetilive days.

It is also humbling to know how dedicated our followers are and what support we get from them. Our fun would have been over long ago if the community had not backed us. It has occurred to me that Snapshot Serengeti’s followers do so in differing ways. Those who follow our facebook and twitter pages or WordPress fans who follow us through our blogs may have missed what it is we are up to. So at risk of boring those of you who do know I thought it was about time to reiterate what it is we at Snapshot Serengeti do and how it all works.

Our largest group of followers do so at www.snapshotserengeti.org helping us classify the millions of camera-trap images that are produced by around 225 camera-traps placed in a permanent grid pattern in our study zone in the Serengeti National Park. For continuity’s sake these sites, after an initial bit of trial and error have remained in their fixed spots since they were first chosen by the projects designer, Dr Ali Swanson back in 2010.

Originally the camera-trap grid was set up to answer questions on carnivore interactions specifically if carnivores were avoiding one another spatially and temporally, it soon became apparent that it could be used to pose many more scientific questions amongst them herbivore coexistence and predator prey relationships. The wisdom to leave this permanent window of observance into the lives of the Serengeti animals should lead to many future studies and has spawned many new similar camera-trap projects around the world.

It’s not all about the animals, in fact since teaming with Zooniverse the project has been as much about the advancement of citizen science as anything else. Back in the Serengetilive days there were so few of us taking part that we used to have our names up in a sort of league table of who had classified the most images. Each classified image was labelled by the classifiers name. Now of course there are far too many participants to bother with that kind of thing, besides with multiple people having to agree on each classification it might get messy. The work on developing a robust algorithm that dealt with the uncertainties in each individual classification was so involved it also paved the way for many more projects and several scientific papers.

So what do we ask classifiers to do? Well first you are presented with either a run of 3 images (day time) or 1 image (night time). You are then asked to decide and record what animals are present, numbers of each species, behaviour and whether there are young present or not. It’s pretty straight forward with prompts along the way. If you don’t know what the animal is you simply guess. Yes you read that right, you guess. One thing the developers worked out is that the whole project works better if you cannot skip images. For one thing it avoids all the hard or boring images being left till the end. As each image has to be agreed upon by several classifiers before it is retired this tends to smooth out any miss classifications and research has shown we are around 97% accurate.

If you find something good or something you cannot id and are curious you can add the image to Talk which is the discussion forum. There we have some very dedicated moderators who will help you with your queries.

All in all Snapshot Serengeti is about learning and sharing both for the researchers and for the community of classifiers so if you have been enjoying the facebook posts or reading the blogs but have never had a go classifying get yourself over there to www.snapshotserengeti.org and have a go.

The Other Great Migration

White Stork

 

I am sitting at home in France in a sweltering 40oc listening to golden orioles calling from the tall riverine trees. I could definitely be in Africa, though if I was I would probably be somewhat reluctant to jump in the river to cool off, something I am about to do, what with all the hippo and crocs that the Serengeti is so famous for.

It has got me thinking though about all our shared birds between Africa and Europe. Hearing the orioles today has made me realise that they will be setting off very soon, in the next couple of weeks probably, for their return trip to their wintering grounds in Africa.

Now the Serengeti is justly known for its rather famous herbivore migration but to me it is utterly fascinating that birds, particularly the tiny ones are also taking part in seasonal movements that cover 1000’s of kilometres.

It’s a dangerous journey, they risk predation, starvation and severe weather and if that’s not enough they have to pass over several places where humans think blasting as many of them out of the sky as possible is sport. For the birds migrating from Europe to Africa they have to fly over open sea and a lot have to negotiate the Sahara Desert, an area around the size of the United States. It is estimated that 500 million birds have to cross this unforgiving wilderness and some do it in a long nonstop flight. Just imagine how exhausted they are the when they reach the safety of the green belts that fringe it. My husband used to work in the Sahara and can attest to finding dozens of swallows just lying panting on the ground, being able to pick them up and give them water before launching them onwards.

So why do they do it, well much the same reason as wildebeest and zebra do, resources. Birds have the very special ability to travel very efficiently, it has been said that a small bird can fly the same distance in hours that an elephant would cover in three days. With this ability birds are able to switch geographical areas in order to take advantage of seasonal food supplies and so they enjoy the best of both worlds in terms of food abundance despite the risk involved with moving the great distance between the two. Risk versus reward.

Unlike the Serengeti herbivore migration birds have many different strategies when it comes to undertaking their colossal movements often depending on the species unique design. Many small passerines will migrate in small groups, travelling at night and will try for the shortest, most direct route. A kind of fast and furious approach that relies on having fed up well and being able to feed quickly at the few places they do stop to refuel. Other birds, particularly waders will take a more leisurely approach flying down waterways and coasts, stopping for days or weeks at a time to feed up before moving on. Many raptors and storks cross the Mediterranean Sea over Gibraltar and Tarifa in Spain. It is roughly a 14 kilometre crossing. It is an amazing spectacle to see. Thousands of birds can be seen soaring around in the late morning over land waiting for the thermals to build up which they will use to ride across the sea to Africa. It’s kind of like surfing only on hot air.

Once they get to Africa of course they have a huge choice of where to go and they spread out accordingly, many making it all the way to South Africa. In fact we still don’t know where a lot of them go, something that is vital to understanding the threats facing them today.

So who are the feathered migrants that we may see in the Serengeti? Well across Tanzania there are thought to be around 160 species of Palaearctic/African migrants. The Palaearctic is a large region covering Europe, Russia, North Africa, Arabia and parts of Asia so that’s a lot of movement.

Some of Europe’s smallest birds can be found in the Serengeti amongst them willow warblers, wood warblers and blackcaps. Spotted flycatchers and several shrikes can be easily seen. The common cuckoo is trickier as it is, like many migrants, silent outside of its breeding ground. European bee-eaters and rollers meet up with their African cousins as do barn swallows and common house martins.

Even raptors make it to the famous park; lesser spotted, steppe and imperial eagles all breed in the Palaearctic. Eurasian marsh harrier, black kite and common buzzard all enjoy the warm African conditions before heading back north to breed.

For Snapshot Serengeti followers the most commonly seen migrants on our camera-traps are probably storks, white storks and black storks all take the long journey north for breeding. More surprisingly given it is not noted for its water even European ducks have been spotted in the Serengeti, wigeon, Eurasian teal and garganey amongst them.

This is not an exhaustive list but gives you an idea of the level in which the two continents are connected through their shared avian fauna and reminds us of what a truly global planet we live on.

Snapshot of a Crossroads

When we think of Snapshot Serengeti we think about the massive array of 225 camera-traps that are spread over 1125 km2 in the Serengeti National Park permanently clicking away. Partly this is fostered by the fact that when citizen scientists help out classifying images for the project they are randomly assigned images from a mixture of the 225 camera-traps rather than a sequential set from one camera. This is done so that each member of the community gets the chance to see a good range of different animals rather than, say, getting a camera-trap that was triggered 1000’s of times by grass.

For the most part anyway, people are concentrating so hard on the animals in the image that the scenery in the back ground is almost incidental. Regular contributors though will be aware that there are one or two camera-traps that are in very recognisable locations for example one trained on a group of boulders and one on a log. For some reason these spots seem to produce some really memorable images; the log was the scene of our melanistic serval as well as lion cubs, the boulder gave us some stunning images of spotted eagle-owl.

Recently the most epic capture event ever on Snapshot Serengeti surfaced of a pride of lions hunting a buffalo (if you missed it look here, https://www.facebook.com/SnapshotSerengeti/). That sequence was captured at a special little spot in the Serengeti, Dik-Dik Corner. The view is basically of a lone tree standing at a three-way cross road in animal tracks. There seems to be a pair of dik dik who hold this area central to their territory and they appear regularly, hence the name, but they are certainly not the only ones.

Here is a slide show of the passing wildlife at Dik Dik corner.

This slideshow requires JavaScript.

 

Of course these are not the only critters to have passed this way but this selection really shows how the animals follow the trails, something camera-trap researchers have used to their advantage over the years.

Zorilla

M2E1L0-36R350B300

Zorilla – a rare find!

 

A few years back the Snapshot Serengeti community classified its first ever zorilla (Ictonyx striatus). It’s not an animal that most people are familiar with and you would probably not expect to even see one on a safari in Africa. It is certainly not on the big five list or even on the little five list but just like its bigger cousin the honey badger it’s a gutsy little creature.

The zorilla, or African striped polecat belongs to the Mustelidae family that includes the well known honey badger, otters and weasels. Although superficially similar looking to skunks they are unrelated.

So how would you recognise one? First of all they are small, only 28 – 38 cm long with a bushy tail of around 25cm. The most striking feature is the black and white stripy coat. The body is overall black with four white stripes running from the head to the tail which is mostly white. There are white patches on the face and head and the small ears are often white rimmed. The fur is quite long lending the zorilla a slightly scruffy appearance.

Zorillas share more than their looks with skunks; they are also able to squirt noxious smelling liquid from their anal glands as a defence mechanism against predators. So if you do ever encounter one, give this little guy the respect it demands and stay well back.

These tough little creatures will eat a wide range of items, invertebrates, reptiles, rodents and birds but they seem to favour rodents and insects. They are known to tackle venomous snakes and large rats by pinning them to the ground and repeatedly biting at the back of the neck to make the kill. Nocturnal, they find most prey by smell and won’t hesitate to follow prey down into burrows or use their strong claws to un-earth something. Its small elongated size is perfectly adapted for this task.

Zorillas are found across sub Saharan Africa in a wide variety of habitats but seem to avoid the wetter rainforest belt through west and central Africa. They are mainly terrestrial but are known to be good climbers and happy to swim if needed. Due to their widespread presence in Africa their conservation status is classed as Least Concern by the IUCN red list.

So why don’t we see more on our camera-traps? Well not much is known about zorillas, their small size and nocturnal habits make them hard to study and in a place like the Serengeti they are just not a high priority species. However we do know they are present because they do show up on the camera-traps from time to time. I suspect that the main reason they are not picked up more frequently is their small size coupled with their fast paced frenetic life. The weasel family is notoriously hard to capture on camera-trap as they tend to shoot through the trigger zone before the camera has got its-self together to trigger. Perhaps we will see more zorillas in the future when the camera trigger speeds increase.

 

Lions

This slideshow requires JavaScript.

 

This is a great sequence from one of our 225 camera-traps that are tirelessly snapping away in the heart of the Serengeti National Park. One of the largest and longest running camera-trap projects, Snapshot Serengeti has been running for over 8 years with out a break.

The millions of images generated by so many cameras are processed by the amazing online community of citizen scientists without whom the team of scientists would probably still be working their way through season 2 rather than ploughing their way through season 10 (that’s were we are at currently, November 2015 to September 2016).

Those of you who have helped out on Snapshot Serengeti will realise that there is a great variety of images that come up, they are randomly assigned to each classifier and currently have to have at least 10 matched classifications before being retired. A great many are of grass or the tail end of animals as they pass by. Its the frustration of camera-trapping, when you look at the results you just wish you could nudge the camera to the left a bit to get a better image but of course its way to late for that once you have the image safely in hand.

But every once in a while we get a stunning image worthy of a professional photographer or one that shows really interesting behaviour and those are the images that get people hooked on returning day after day to help out on Snapshot Serengeti. A little fix of wildlife in its environment enjoyed from your home.

This sequence of a lion pride is great. In all likely hood the four individuals we can see here are not the only members, others could be out of frame. It looks as though the female has a pink tone to her muzzle, now it could be a trick of the light but its also possible that the pride have recently fed. The full looking belly and the relaxed nature of the other members would lend weight to this possibility but we will never know for sure (unless more images from that camera-trap reveal more proof!)

It is most definitely one of those moments when you wish you could pan the camera around to see what else is going on, did we almost get a kill on camera? are there a bunch of cubs laying under a bush to the right? are there a pair of resplendent pride males slumbering to the left?

If you do discover more from this series do let us know but for the time being we shall have to let our imagination ramble.

The African Buffalo, Success in a Crowd

African Buffalo Herd

 

 

Lately we seem to have had some great buffalo images. These big imposing beasts aren’t exactly pretty but they have an appeal of their own with their imposing bulk.

There are 4 recognised subspecies of the African buffalo (Syncerus caffer), three savannah buffalo and one forest buffalo. Here in the Serengeti we find Cape buffalo (S c caffer) the biggest of the three savannah species also known as southern savanna buffalo. It weighs in at a whopping 500- 900 kg for males or 350-620kg for females. The two other savannah species are West African savanna buffalo (S. c. brachyceros) and Central African savanna buffalo (S. c. aequinoctialis) both slightly smaller than their Cape buffalo cousins.

The forest buffalo (S. c. nanus) appears quite different being redder in colour and quite a bit smaller weighing around 265-320kg but it is thought that this is in fact the ancestral African buffalo from which the others evolved. According to the IUCN Red-List although the three savannah species appear similar they are at least as different from one another as they are from the more distinct forest buffalo. Defining subspecies is always tricky and apparently there is hybridisation where these different subspecies meet, including between savannah and forest subspecies. I witnessed this when working in the Central African Republic where you could see smaller red ‘forest’ type buffalo intermingled with bigger looking dark ‘savannah’ type.

So what makes African buffalo so special? You would imagine that such a large animal would not seek safety in numbers but this animal is highly gregarious. Herds can reach thousands strong but these tend to be temporary and the usual number is dozens to hundreds formed of clans of related females and their offspring and an assortment of males. The rest of the males form small bachelor herds of 5-10 animals or live alone.

Living in these large herds gives buffalo a certain security and they are highly protective. They are known to chase predators as a herd in order to ‘rescue’ a targeted individual. They don’t hesitate to run at lions if they are threatened. This is to be expected when there are young calves about but buffalo herds are known to extend this behaviour towards injured, sick and even blind herd members. It is so effective that it is actually males not living in large groups, particularly the loners that are most often preyed upon by their arch enemy, the lion. When buffalos are on the move dominant females lead the way with mothers and calves in the centre followed by any infirm individuals and older cows with males forming a protective ring around the entire herd.

Formidable indeed but of course the very thing that allows them to be so aggressive, their size, is also the thing that attracts lion the only true threat other than man to an adult African buffalo.

As a species the African buffalo is listed as ‘least concern’ on the IUNC Red-List due to its widespread distribution. That doesn’t mean that there are not conservation issues. Buffalo are often targeted by poachers for the obvious reason that they provide a rich reward in meat, the usual land reduction is a factor and in areas outside game reserves they are often killed as they compete with domestic cattle for food.

Historically buffalo numbers plummeted in the 1890’s due to the rinderpest epidemic that saw the disease spread from domestic cattle to wild ungulates. The disease continues to have small outbreaks. More recently bovine tuberculoses, again spread from domestic cattle to buffalos, in the Kruger National Park has also caused mortality as well as triggering a cascade of health issues in other animals, in particular, lions who eat infected buffalo. A whole industry has grown up with the sole purpose of breeding TB free African buffalo in South Africa. On the whole though African buffalo are well represented with strong populations in protected areas and as long as these remain their status looks to be stable.

The male and female have large horns that are fused at the base forming a boss across their heads, in the male though this becomes thickened and sometimes massive and fighting males will crash bosses together if things become serious and posturing doesn’t work. The impact is so intense that they risk killing themselves or their rivals.

 

Big male Cape buffalo

 

 

Next time you find a buffalo image, see if you can work out if it is male or female and take sometime to reflect on these formidable beasts.

New and Improved Image Batch

This slideshow requires JavaScript.

 

Last week the amazing community of classifiers on Snapshot Serengeti managed to complete the current batch of images. That doesn’t mean that this season is done with. It used to be that the whole season would be uploaded all at once on to the Zooniverse platform but these days with ever increasing image sizes and plenty more projects taking part space has become a bit of an issue. So now we upload in batches.

Normally we would have the new one ready to go straight away but as long time followers of Snapshot Serengeti may have noticed we have been having some image quality problems since swapping over to a new Panoptes platform.

We have finally found someone who is able to sort out this problem for us and he is working on it as we speak but the Snapshot Safari team decided that delaying the new batch of images for a short while to bring you better quality images to classify was worth the wait.

So we will be back shortly, new and improved and hope that it will improve your experience on the site.

In the meantime here is a sequence of cute elephant interaction captured in the last batch. Enjoy.

 

 

Image Quality Explained

hyena

A Snapshot Serengeti Camera-trap image

Those of you who have been with us for some time will probably have noticed that the image quality since we switched to the Snapshot Safari platform has reduced, sometimes dramatically. Before I go any further, we are trying hard to fix this but in the meantime I thought I would try and explain what the issues are in a hope that it may induce a little more patience from you. I am afraid that I really am technically challenged when it comes to computer stuff so I am going to be a little vague here but please, if there is anyone out there with more knowledge who can either help explain more appropriately or better still offer our team help don’t hesitate to get in touch.

So the trouble all started when Snapshot Serengeti joined the bigger Snapshot Safari platform at the start of this year. At this time Zooniverse was having a big overhaul with older projects operating on Ouroboros moving over to the Panoptes format. Essentially Ouroboros and Panoptes are both software packages which enable projects to build their pages and run them.

Of course Snapshot Serengeti being one of the oldest Zooniverse projects was designed using Ouroboros and has had some teething problems with the switch over. One thing to remember is that the teams involved with bringing all the camera trap images to the Snapshot Serengeti platform are for the most part unpaid graduate and undergraduate students studying ecology. They are not experts in computer programming yet have to keep the platforms running and fix all the problems.

In the old days the University of Minnesota based team would upload the batches of images from the camera traps and send them to Zooniverse who would process and upload them to the platforms. That was when there were a dozen or so projects. There are now over 50 active projects. Can you imagine how long it would take for Zooniverse to do all the uploading? To address this problem they have asked individual projects to manage the uploading themselves. To complicate this process a little more they have also placed a 600GB maximum file size on the images.

This all means that the team of ecologists at Minnesota have to engage computer code developers to write custom scripts enabling their super computers to interact with the Zooniverse web platform. The image quality issue then is not because we have started using different camera’s or taking images at a lower resolution it is due to the code that compresses the images from their full size to less than 600GB. Those images that were smaller in the first place have been less effected than the larger ones and hence the mixture of quality that we are seeing.

So as I said earlier we are trying hard to get this problem sorted and bring you back the kind of top rate images you are used to and hope to have things sorted with the next batch of images we upload. In the meantime please spare a thought for the team and remember that like you they are all volunteers, all be t with a slightly more vested interest in the research project. I hope that you will bear with us and keep up the much needed support you have always given us.