Archive | Camera Trapping RSS for this section

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.

Advertisements

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.

 

A Touch Of Colour

After my latest field trip to Namibia I was fortunate enough to spend a few weeks visiting some old haunts in South Africa. Even though I had very little time and no real scientific purpose other than curiosity I could not help but put out my camera traps whilst I was there. It was after all a nature reserve and surprises can happen.

One of the camera traps was located on a well used animal track that lead from the bush down to the river. The rains had not thus far been kind in that part of Africa and the bush was rather dry with little standing water so I was confident the track would offer some interesting images. As expected I had lots of images of vervet monkey, warthog, impala, nyala and waterbuck. Imagine my surprise then when I scrolled through 20 or so images of a small herd of waterbuck does with young to find this fluffy looking white thing that looked more like a sheep!

 

Leucistic Waterbuck

 

 

In fact it was a leucisitic waterbuck. Not to be confused with albinism, which is a condition caused by absence of melanin leading to pale skin, hair, feathers and eyes, leucism is defined as a partial loss of pigmentation that leads to an animal appearing pale or patchy but often with patterns still showing. The eyes in animals with leucism are normally coloured never the red that can occur in albinism. So albinism is a lack of melanin and leucism is a partial lack of melanin.

You can see this little waterbuck still has the distinctive bulls eye target ring around its rump that distinguish the common water buck from the Defassa waterbuck we are used to in the Serengeti proving it is leucistic not albino.

Regardless of which of the two conditions it has the young animal will have a tough time. The pale colour makes it stand out as a target to predators and it is thought that survival rates for leucistic animals are low. That’s not to say it won’t make it to adult hood, in fact the white lions of the Timbavati are a well followed case of leucism in a population that every now and then throws up a white cub or two, they are so well watched that it is known that some do survive into adult hood. From those few individuals stem most of the white lions that can be seen in captivity in zoos all be it showing all kinds of horrible traits of constant inbreeding.

After finding these images I was lucky enough to spot the herd with my own eyes. I watched the little leucistic waterbuck playing and frolicking with a like aged normal waterbuck and for all the world you wouldn’t know what all the fuss was about. The two were identical in every way except the pure chance of a mutated gene governing colour. Good luck to the pair of them.

Best of Friends

wildebeest and zebra

 

Symbiotic relationships are common in the Serengeti. They fall into two main types, mutualism, whereby both partners benefit from one another and commensalism, whereby one partner benefits from the actions of the other but the other partner is largely unaffected or unharmed. I wrote recently of oxpeckers and large herbivores, large herbivores provide food in the form of ticks for the oxpeckers and oxpeckers provide a cleaning service for the large herbivores, a good example of mutualism. Birds such as cattle egrets that follow buffalo around to catch the invertebrates the buffalo disturb as they graze is an example of commensalism. Of course it is not just animals that have symbiotic relationships; my blog last week on termites and mushrooms was another example of mutualism.

So what about zebras and wildebeests? We see them all the time on Snapshot Serengeti in mixed herds, grazing peaceably with one another. Is this just coincidence or is this a form of symbiosis?

It is actually hard to say and of course that is why labelling things, especially behaviour is often tricky.

Zebra and wildebeest are both grazers meaning they mostly eat grasses but that doesn’t mean they share the same diet. They preferentially eat different parts of the plants that they consume. Zebras are quite content chewing longer tougher grasses where as wildebeest prefer shorter, more tender shoots. This partition of resources means they can quite happily graze side by side with out exerting pressure on each other.

Another good reason to team up is the extra safety that numbers provide. Not only do more ears and eyes provide better early warning systems but the odds of the individual being targeted by a predator are reduced when there are greater numbers to choose from. Apparently zebra have better eyesight but wildebeest have better hearing so the two complement each other.

There could be another reason. Our very own Meredith Palmer just published a paper about interspecies reaction to each other’s alarm calls, you can read it here: https://www.sciencedirect.com/science/article/pii/S0003347217304207

She found that zebra, wildebeest and impala recognise each other’s alarm calls but that they did not always respond in the same manner. When zebra sounded the alarm all three herbivores reacted strongly but when impala gave the alarm zebra where likely to ignore it, or assess the relative danger themselves. It seems that this varied response is down to predator size. Impala are prey to a wide range of smaller predators that would not be able to handle a mammal the size of a zebra, so when impala give the call it doesn’t always signal danger for the zebra. However when a zebra, the largest of the three herbivores sounds the alarm, whatever it has seen will probably be able to take down the wildebeest or the impala too so it’s prudent that all three scarper.

It is an interesting reaction and maybe wildebeest hang out with zebra because they are more trustworthy alarmists. I am not sure that the companionship of zebra and wildebeest can be classed as symbiotic I think it is more of an interaction due to a shared habitat but it seems that on some level they can benefit each other.

The Giraffe and the Oxpecker

IMAG0415

 

Those of you who follow our Facebook page will have seen recently that Meredith Palmer, one of Snapshot Serengeti’s scientists and PhD candidate with Minnesota University just published a paper in African Journal of Ecology with the catchy title;

Giraffe Bed and Breakfast: Camera traps reveal Tanzanian yellow-billed oxpeckers roosting on their large mammalian hosts.

The paper highlights one of the more unusual behaviour traits documented by our cameras and discovered by our classifiers of yellow-billed oxpeckers (Buphagus africanus) roosting on giraffe at night time.

Those of you that have been with us a while may have had the pleasure of finding one of these night time images of giraffe with oxpeckers tucked up safe and snug between their back legs. In fact I wrote a blog about this back in 2014.

https://blog.snapshotserengeti.org/2014/01/17/the-curious-case-of-the-giraffe-and-the-oxpecker/

Two species of oxpecker are found in the Serengeti, the red-billed and the yellow-billed oxpeckers. Whilst the red-billed will feed from a wide range of hosts from impala and wart hog to hippos the yellow-billed oxpecker is more discerning and prefers large hosts such as buffalo, eland and giraffe. The problem with this choice is that these animals are far roaming and if the birds were to find trees to roost in at night, and these can be sparse in the Serengeti, the yellow-billed oxpecker could struggle to locate its host the following morning. It seems they have overcome the problem by staying over on the hosts. What’s more is these clever birds have opted for the premium rate rooms where they are not disturbed during the night for, as is well documented, giraffe almost never lay or sit down at night time preferring to stay upright.

So although during the day yellow-billed oxpeckers are found on several large mammal hosts most of the night time images are of giraffe roosts. It seems they also have a preference for the groin area of the giraffe. It is not hard to imagine that this would be the warmest safest spot on the giraffe, the cavity created where the two hind legs meet is spacious enough to accommodate a small flock of birds and of course is also very attractive to ticks so if they fancied a mid-night snack…..

It is these unexpected discoveries that make the project so exciting and worth all our effort in taking part so next time you are racing through the classifications take a little time to have a closer look at the images, you never know what is waiting to be discovered.

 

If you want to read more about Meredith’s paper you can read the following:

https://news.nationalgeographic.com/2018/02/animals-serengeti-tanzania-birds/

 

 

 

 

Welcome New And Old

Lion pride

So the new Snapshot Safari base camp for Snapshot Serengeti is a month old and teething problems aside all seems to be going well. I just wanted to take this opportunity to welcome all our new classifiers and to say a big thanks to all our old classifiers who have stuck with us. But most of all a massive thank you to our moderators who have worked so hard to make the transition run so smoothly. They have answered all your questions and queries without my back up due to the unfortunate timing of my own African field trip falling during the launch of Snapshot Safari.
It is not the first time Snapshot Serengeti has seen a big change. Some of you may remember its first outing as Serengetilive back in 2011. In those days things where a lot slower, you started classifying by first choosing an individual camera and working through it. There was an option to skip images, leaving them for someone else. Of course what ended up happening was all the hard to identify images and all the no animal grassy images were left to the end so that some people never got the chance to classify any animals.
We then progressed, in 2012, onto the Zooniverse platform and saw a huge change to the way things worked. Suddenly there was a lot more interaction between the scientists and the community. This was when the famous algorithms where developed by Margaret Kosmala and Ali Swanson and their team to act as a fail proof to anyone incorrectly identifying images.
We are all very grateful for their hard work and dedication that results in us classifiers being confident that our guesses won’t mess everything up.
So I hope that you are enjoying this third incarnation of Snapshot Serengeti and can be proud that it has worked so well over the years that it has spawned so many new projects.
My own field trip to Africa is coming to an end this week and I will be back in the land of internet connection. I will then hopefully be bringing you more regular posts and more updates on the project itself and how it is progressing. In the meantime don’t forget to check out our facebook and twitter pages.

Observations on Observations

White-browed sparrow weaver nests

 

Camera-trapping has vastly opened up the possibilities of studying animals in the field in a relatively unobtrusive manner. Leaving a bunch of camera-traps clicking away 24/7 over a long period is generally cheaper than employing researchers to stay in the field providing them with accommodation, food and vehicles.
However it has its drawbacks. Good field skills are only learned over time spent in the field and although field researchers cannot operate 24/7 like the camera-traps they are less impartial observers noticing all kinds of fine details surrounding that which they study.
It is these observations that stimulate and inform new scientific questions and drives the understanding of the world around us. I am not suggesting that the results of camera-trap studies can’t also do this but since the days of the first naturalists it is being in the field that nurtures the very interest in studying wildlife in the first place.
The researcher who knows their study area well will be at an advantage to one who has planned from afar after using GIS. I know because I have been both. My first camera-trap project was on a reserve where I had lived for three years and that helped me know intuitively where I should place my camera-traps. On the other hand my latest project involved a very fine time window and I had to set up camera-traps on an unknown farm within two days of arriving. By the end of the 8 week period I was just starting to get a better feel for the place and could have kicked myself for not placing my cameras in the optimum places. When I went back to collect the cameras I found myself wading thigh high through a carpet of small yellow daisy-like flowers that left me coated waist down in a yellow stain. Had I have known the farm better realised this plant grew only in a few areas and could have avoided it entirely and saved myself the turmeric skin wash and a lot of miss-triggers.
My latest trip to Africa reminded me of why living in the field is so rewarding. Whilst the camera-traps are diligently collecting your data it gives you the chance to observe without frantically thinking of your research question, you can take time to take inspiration from the broader environment.
Near my tent was an old dead knob thorn tree that had five white-browed sparrow-weaver nests hanging like straw balls from it. Each night at dusk a pair of sparrow weavers would fly into the tree, call loudly as if claiming the spot and the female would dive into her preferred nest. The male would remain up high above waiting. Just as the last light was fading 3 or 4 small dark shapes would arrive and the sparrow weaver would chase after them squawking disapproval. Having seen them off he would come back and settle himself into the nest of his choice retiring for the night. Watching closely revealed, a few minutes later, the return of the invaders; two pairs of black-faced waxbills. They alighted at the top of the tree and cautiously made their way down towards the remaining nests finally one by one slipping quietly into the unused nests one couple per nest.
The thing about this little drama was that it was played out every night for over two months. None of the birds seemed to alter their routine and none where actively breeding at the time, they just had their bed time ritual. This was the kind of observation that the camera-traps will never quite capture as well as a human. In just the same way, although Snapshot Serengeti would not exist without the cameras it would be nothing without the human, citizen scientists behind the scenes sorting out the images. Even with computer recognition programs on the horizon I believe it would be foolish not to still use humans who’s innate sense of life will always pick up on something that is slightly odd, unusual or different about an image.

Camera-trap Conundrums

You are probably aware that the 225 camera traps of Snapshot Serengeti are set out in a grid pattern, spaced every 1km over a part of the Serengeti National Park. It sounds relatively simple but actually there is a lot of painstaking scientific pondering as to how exactly to set out your camera traps.
Over the last couple of decades there has been much debate as to the best way to design a camera trap study. The main choice, in terms of placement pattern, is whether to place your camera traps randomly or selectively and what kind of spacing/density to use.
Truly random is to grid your study site and then let a computer randomly choose which grid squares to place the cameras. Alternately you can choose a line or grid and place your camera trap at regular intervals regardless of where that may fall, still a random point. With selective placement each site is carefully chosen for a specific feature.
In reality most projects use a mixture of the above methods and the best method is really determined by what your scientific question is. For instance, if you where trying to acess the number of leopards in a given area it is better to place your camera traps strategically in places you know or guess leopards are most likely to pass rather than using a randomised method. However if you are carrying out a census of an area and wish to know what species are present then a randomised grid is ideal.
As I said a mix of methods is often used. Imagine setting out a grid in the comfort of your office on your computer. It looks good, covers a large area and promises good results. Once out in the field you navigate to your carefully worked out GPS reference point only to discover it is slap bang in the middle of a marsh or in a thick overgrown patch of thorn trees. This is where the scientists allow themselves a little leeway. Often they will take the GPS point as home base but choose an ideal spot within a certain radius of this point where perhaps there is a game trail or some other sign of animals passing, thus allowing them to select a good site within the vicinity.
I have recently had experience of this type of placement and I can say the work done in selecting your study site and then laying out your grid onto a map is laborious but not nearly as much as stomping through the bush keeping your fingers crossed that your next randomly selected site will be perfect. Turning up to emplacement three to find a thick tangle of vegetation is a little soul destroying, mostly you wonder if any animal is likely to bother to pass that way. The reality is that you normally find a spot that is better within 10 meters and with some slight pruning of the vegetation the sites can often turn out remarkably productive.
So that is the placement sorted but there is a long list of other agonising variables to consider, what settings to use on the camera trap itself, how many to use and how long to keep them up. Believe me every scientist designing studies deliberates the pros and cons of these factors and worries incessantly about if they have made the right choice. You don’t want to set up all you camera traps and leave them for a few months only to find your set up was not great, something which happened to me recently when I chose to set the camera trap on high sensitivity to make sure I had every chance of capturing the small, fast critters. The problem was it was so hot, 40°c plus, that the ambient waves of heat set the camera trap off almost permanently between 12pm and 5pm leaving me with 2000 images of nothing. I have had to compromise and reduce the sensitivity to avoid all the miss triggers; hopefully it won’t miss too many small things.
Snapshots camera traps have now been up for over 7 years so most of these teething problems have been ironed out. But as with the best laid plan you cannot control everything, the odd camera still malfunctions as I am sure that our regular classifiers can attest to!

Camera-trap

Snapshot Serengeti – Upcoming Changes

*This weeks blog was written by Jamee Snyder, project coordinator and administrative assistant with the Lion Lab, University of Minnesota. She tells us all about a wider a project that Snapshot Serengeti has evolved into and what we can look forward to in the near future.*

 

Seven years ago, the University of Minnesota Lion Center set out 225 cameras in Tanzania’s Serengeti National Park. These cameras have recorded over 50 species including some of the most threatened species on Earth. With help from over 140,000 citizen scientists from around the world, millions of photographs were reviewed and classified over the past seven years, which provided park managers, conservationists, and researchers with the necessary information to analyze African wildlife population dynamics. This collective effort is a major contribution to ecological research, allowing for the evaluation of long term trends in wildlife populations as well as best practices in conservation management of charismatic african mammals.

hyena

A Snapshot Serengeti Camera-trap image

Snapshot Serengeti was one of the first camera trap surveys to document wildlife populations in a national park and is now one of the longest running camera trap surveys in the world. We have learned a lot over the years, from how to keep our cameras safe from hyena jowls to retrieving data from memory cards that have gone through a wildfire. We are continuously looking for ways to improve this project.

Thanks to years of experience, your participation, and help from several organizations in the U.S. and Africa, we are excited to announce that Snapshot Serengeti is expanding into an international conservation initiative called, “SnapshotSafari.”

Untitled

Don’t worry! Snapshot Serengeti isn’t going anywhere. In fact, it will remain essentially the same as we transition into our new platform. The discussion forums and personal image collections will still be available to current and future users. Now, participants will be able to see numerous other parks in addition to the Serengeti. SnapshotSafari will showcase camera trap images from multiple camera trap grids inside dozens of parks and reserves located in six African countries. Intrepid citizen scientists will be able to choose from various exotic habitats, including but not limited to: the Sand Forests of KwaZulu-Natal, the Lowveld of Limpopo, the Fynbos of South Africa’s Cape, and the Karoo desert, in addition to such remarkable ecosystems as Mozambique’s Niassa Reserve, Tanzania’s Ruaha National Park, Swaziland’s Mbuluzi Game Reserve, and Botswana’s Makgadikgadi Pans National Park.

By incorporating multiple sites, we can ask more complex questions regarding African wildlife populations and the factors that contribute to ecosystem stability. For example, researchers can compare population dynamics of reserves that are fenced versus those that are unfenced, or theycan evaluate the environments that successfully host multiple predator species without depleting prey populations. Researchers at the Lion Center will use this dynamic platform to investigate the cascading effects of large mammal reintroductions and ways to limit direct human interventions while still maintaining stable ecosystems within fenced reserves. SnapshotSafari provides an opportunity for participating reserves to collaborate and subsequently develop the most effective conservation strategies for protecting biodiversity.

We are working hard to get SnapshotSafari ready to launch in January. We just completed beta-testing, and the feedback has been very positive. To all of the citizen scientists who participated and to those who continue to be involved with Snapshot Serengeti, we are extremely grateful!

Now, we need your help to finish classifying the final series of images on our original platform, Season 10, at http://www.snapshotserengeti.org before we initiate SnapshotSafari, which will host Season 11. We are very close to finishing classification of these images, so don’t hesitate to invite your friends and family to take a trip to the Serengeti through the lens of one of our camera traps and classify wildlife. Let’s push this meter to the end!

Stay tuned for an official count down, so you can be one of the first to participate in SnapshotSafari and contribute to our collective knowledge and ability to successfully conserve African wildlife.