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Wildlife Photographer of the Year

Well it is that time of year again when the winners of the prestigious wildlife photographer of the year awards are announced.

Having a browse through this year’s winners I notice with a touch of sadness but a good dose of hope just how many of the photos touch on the demise of wildlife and have a conservation message. Brent Stirton’s moving image of a poached black rhino although tragic is a strong weapon in itself in the fight to change the hearts and minds of those people that covet rhino horn.

One of my favourite images is in the bird behaviour category. The much maligned marabou stork is the subject and the shot was taken in the one spot on this planet that Snapshot Serengeti fans know so well, yes the Serengeti.

But the story doesn’t end there. The photographer who was awarded finalist in the bird behaviour category is well known to us. Daniel Rosengren worked for the Serengeti Lion project for 5 years in the field with the most enviable job going. He spent every day following the study lions getting to know them intimately and generally building up the rich source of study data that this 30 year+ project has gained.

Of course when Dr Ali Swanson came up with her wonderful idea of seeding the area with 200 odd camera traps and the Snapshot Serengeti project was born it was Daniel who looked after our precious cameras for several years. So we have a lot to thank him for.

Daniel moved on from the project in 2015 to pursue a career as a professional wildlife photographer and we congratulate him on his achievement this year in the wildlife photographer of the year award. Well done!

If you want to learn more about the story behind his image or just want to see some stunning wildlife images visit his website here http://danielrosengren.se/wpy-awardee/

And to see all the other winners from this year’s wpy 2017 visit

http://www.nhm.ac.uk/visit/wpy.html

 

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Weekly Round-up

This week we have had a lot of great images that our community of classifiers have flagged up for discussion. Numbers seems to have been the theme, with unusual sightings of two aardvark stepping out together, elephant herds and lion prides.

My favourite is the unusual grouping of three dikdik, almost certainly a family unit, all looking behind as a bushbuck saunters past.

So here is a taste of the action:

 

 

 

Hot air balloon

 

Zebra

 

Lion pride

 

What will you find this coming week? Don’t forget to share the best or the unusual with the rest of the community. Head over to https://www.snapshotserengeti.org/

 

Celebrating Owls

Sotted eagle-owl

Spotted eagle-owl

 

Although mammals are the target for the Snapshot Serengeti camera-trap project we do on occasion capture other things, humans, vehicles, reptiles and birds. The most common of the birds is probably the larger ground patrolling species like kori bustard, secretary bird, guinea-fowl or the birds that are attracted to mammals like oxpeckers, egrets. It is actually surprising just how many species we have picked up over the years.

One of my favourites though has to be the owls. Always such fascinating creatures they are often loved but often feared too. Their nocturnal, silent flight lends to the mystery but anyone who has been around owls much will know that they can be noisy birds when it comes to calls.

So who might we encounter in the snapshot Serengeti camera-trap images. Well there are 9 species that call the Serengeti home:

  1. Barn owl – Tyto alba
  2. African marsh owl – Asio capensis
  3. Spotted eagle owl – Bubo africanus
  4. Verreaux’s eagle owl –Bubo lacteus
  5. African wood owl – Strix woodfordii
  6. Pear-spotted owlet – Glaucidium perlatum
  7. Southern white-faced scops owl – Ptilopsis granti
  8. African barred owlet – Glaucidium capensis
  9. African scops owl – Otus senegalensis

The barn owl found on every continent except Antarctica is probably familiar to us all. The spotted eagle owl, a medium sized owl is just that, heavily spotted and barred overall greyish. The similar sized wood owl sticks to more densely wooded areas and is a darker chocolate brown. This is a rare bird for the snapshot habitat.

The largest owl we will encounter is the Verreaux’s eagle owl, pale grey the most obvious distinguishing feature is bizarrely its eye lids, they are bright pink. Unmistakeable if you get a good view.

As for the small owls two are actually reasonably active during the day, pearl-spotted and barred owlets. Quite hard to tell apart the pearl-spotted has white spotting on its back where as the barred has, you guessed it, a barred back. However if you are ever lucky enough to hear a pearl-spot in the wild they are unmistakable. It has a slow single note, rising pitch call that builds up to deflating drawn out descending notes. Hard to describe but its other name is the orgasm bird!

We would be lucky to pick up a scops owl, the smallest of all these owls. It remains hidden in trees all day and hunts insects at night.

African scops owl

The African marsh owl is unusual in that it roosts on the ground, tunnelling into long grass. Superficially it resembles a barn owl but the pale facial disc is rounder than the heart shape of a barn owl. They mostly eat rodents.

African marsh owl in flight

The white-faced scops owl has a very striking white face framed by black bands. The rest of its body is pale grey. Size wise it is slightly bigger than the two owlets.

If you want to see more snapshot images of birds follow this link where one of our moderaters has put together some great stuff:

https://talk.snapshotserengeti.org/#/boards/BSG0000008/discussions/DSG0000ek5

 

Dynamic Landscape of Fear

Lions with zebra kill

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

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

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

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

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

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

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

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

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

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

 

Meet The Dikdik, Master Of Cool

 

Male dikdik

 

The Serengeti plains hold a wealth of wildlife familiar to us all. As long as our camera trap images are clear most people have no problem identifying wildebeest, zebra, giraffe and impala. It is some of the smaller antelope that prove a bit of a problem. The smallest of the Serengeti’s antelope, the dikdik is not so well known but what it lacks in size it makes up for in a fascinating life history.

So what makes this diminutive antelope so special and how does it survive living in the lion’s den, so to speak.

It is the antithesis of the wildebeest. Instead of running as a herd of thousands the dikdik live fairly sedentary lives, instead of a constant male battle for mating rights to a harem of females the dikdik forms pair bonds that last for life. Essentially it opts for a quite life under the radar. Living in bushy scrub and kopjes gives it plenty of places to stay hidden and its ability to reach up to 42km/hour enable it to escape even the swiftest of predators. Though of course dikdik do end up on the menu sometimes.

Dik dik are territorial and use dung, urine and scent to mark the boundaries. The scent comes from preorbital glands on the face which is rubbed on sticks. All members of the family will contribute to these markers but it is the male that does most of the work. The strange twist is that males are subordinate to females in the pair bond so really the male is marking and defending his mate’s territory for her. I guess it pays to keep your missus’ happy when you pair for life.

Obviously whilst holding a territory you will have neighbours and that is certainly the case for dikdik pairs but it seems that the peace is kept by making sure you only add more dung/urine/scent to your side of the heap. Dikdik must have the most defined territory of any antelope in the Serengeti. If there is a border dispute it can lead to mass pooping; as many as 10 dung piles per 100 meters which is three times as many as a normal border.

Traditionally there were thought to be 4 species of dikdik mostly restricted to East Africa with one, Damara dikdik, found in Namibia. New work suggests that the four subspecies of Kirk’s dikdik are actually full species making Cavandish’s dikdik (madoqua cavandishi) the species we are familiar with from the Serengeti. It’s hard to keep up with systematics.

One of the most amazing adaptations in dikdik’s is their central cooling system which allows them to live in arid, hot conditions. To cool down they increase their breathing rate from 1 to 8 breaths per minute. This passes over numerous blood vessels in the flexible proboscis (that oversized long snout that makes dikdik look so odd) cooling the blood. From here the cooled blood passes back to the heart through the cavernous sinus. Due to the large surface area in the sinus as hot blood is pumped to the brain a form of heat exchange takes place allowing cool blood to be pumped to the brain ensuring that brain function is not impaired by hot conditions even if body temperature is elevated. This is a trait that dikdik share with other dessert adapted animals such as oryx and camels.

So small it may be but the dikdik is not to be dismissed without some appreciation for its ability to survive in pretty harsh conditions.

Small Cats of the Serengeti

 

Whilst we all love to see lion, cheetah and leopard, the big cats of the Serengeti, their smaller cousins are fairly elusive. I am referring to caracal, serval and wildcat. These three small cats manage to slink around between the large carnivore guild keeping themselves to themselves. Lion cheetah and leopard not to mention hyena will all kill small cats. Despite their diminutive size their larger cousins still see them as competition and threat. All three are solitary cats and to survive in this very competitive world they each have their own niche.

 

Caracal

The largest of the small cats, females weigh in at around 10kg and males up to 19kg. They are found across Africa, Arabia and parts of India preferring drier habitats such as savannahs, steppes and dry woodland. The caracal is a magnificent hunter. It is extremely powerful for its size and is able to take down prey as large as small antelope like duiker and bushbuck. The bulk of their diet is made up of hares, rodents, hyraxes and antelope but they are renowned for their ability to leap into the air to catch flushed birds. Their back legs are longer than their front legs and are endowed with powerful muscles that enable them to burst upwards and snag flying birds.

This cat is uniformly coloured the bulk of its body ranging from a tawny grey to a brick red with some spotting restricted to its pale cream underbelly and chin. Its most distinguishing feature is its black tufted ears and black facial markings as well as a short stubby tail that put one in mind of a lynx. It is in fact not related to the lynx family at all.

 

Serval

Probably the most easily recognised of the three and the most commonly encountered of the cats on Snapshot Serengeti. These exquisite little animals are restricted to the African continent south of the Sahara across savannahs, marshes and forest edges particularly near water courses where tall grassy plants grow.

The serval weighs between 6 and 13 kg with males being larger than females. Proportionate to its size it has the longest legs of any cat species and along with its elongated neck and large pointy ears makes this cat unmistakeable. Its tawny coat is spotted black; these spots may run into bars on its neck, shoulders or legs. Melanistic (all black) morphs are known and we have been lucky enough to capture this rarer variation on Snapshot camera-traps.

Food wise these cats are small mammal specialists stalking prey through long grass locating their prey by sound and then using their long legs to leap into the air and strike prey in a fox like manner. They have very flexible toes and will hook fish and amphibians out of water as well as mammals from burrows. The bulk of their diet consists of small rodents under 200g but they will take reptiles, amphibians, birds and small antelope.

 

Wildcat

These cats are smaller than the other two, heavily resembling a domestic cat it is found throughout Africa, Asia and Europe. They weigh between 2 and 6kg and like the caracal and serval males are heavier than females. Apart from size the appearance of the sexes in all three cats is very similar and show little dimorphism.

Its coat is highly variable in colour and pattern ranging from grey brown to red. Dark spotting tends to appear towards the rump, down the tail and on the legs which often bleed into each other appearing more like dark stripes.

It is perhaps more of a generalist than the other two small cats and takes a wide variety of small prey with rodents making up the bulk of its diet. Birds are less frequently taken but insects have been identified as an important part of the diet. Its method for hunting is more familiar to us than the stalk and pounce of the caracal and serval. It will locate prey by sight or sound and then silently creep towards it by slinking belly to the ground before pouncing at the last minute. We have probably all witnessed a domestic cat stalking like this.

 

Of course once you are familiar with these three cats it is easy to tell them apart, that is if you are lucky enough to get a good daytime or colour image. Although serval are seen out in the day caracal and wildcat are less frequently active during daylight and all three mostly hunt at night. It can be harder to tell one from the other in a black and white night image but the trick is to concentrate on the shape. Does it have outsized ears, long legs and obvious spots (serval) or a rounded head on powerful shoulders and ears with tufts (caracal) or does it really remind you of the proportions of a domestic cat (wildcat). Like always make your best guess and perhaps post on the descussions page for more help.

Progress and stuff

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Some of you will have noticed that our progress bar on season 10 has not been showing any progress. Well it turns out that we have made loads of progress, it’s just the bar that was not getting anywhere.

The good folks at Zooniverse have fixed it for us and you will now see we are about half way through season 10 which is fantastic. There are just under 700 000 images to classify this season so thanks to you, are dedicated team of citizen scientists we have around 350 000 left to go. That’s 350 000 chances of finding that one image you have been waiting for. I have noticed recently lots of you posting on talk that you have classified your first ‘waterbuck’ or ‘serval’. If you haven’t discovered your dream find yet there is still time and yes there is a season 11 in the wings.

Whilst on the subject of talk I wanted to gently remind everyone of a few etiquette points.

#Hashtags, love ‘em or hate ‘em they are part of social media and they are not going away. On Snapshot Serengeti we use them for a specific reason and that is to help others to search for and find certain images.

If you have found a great image that you think others will want to see and you are certain of the species then go ahead and hashtag it, but, if you find an image that you are not sure of then please don’t hashtag it with your guess. You can still put the pictures up in talk for discussion and perhaps someone else will be along who is positive about the id and can then hashtag it. Basically, please use hashtags thoughtfully.

Which brings me to another point; if you can’t identify an image and you post it up for discussion always give us your best guess. No one will laugh; it’s what makes it fun seeing what other people make of the images when you are really stumped. Many a time I have confidently shared a tricky image almost certain for instance it’s a long sort after rhino only to have someone else’s eyes point out that if I look a bit closer that actually it is a rock! Even our expert modifiers get things wrong occasionally and are reluctant to confidently make a call on certain images. Some of them are just so darn impossible to id. So just give it your best shot, it’s what everyone else does.

The main aim is to enjoy yourself, challenge yourself and use other peoples experience when yours fails you. The Snapshot family of classifiers and moderators is a dedicated and knowledgeable bunch and as I have said before, this project would not exist without you all. Keep up the great work one and all.

The Serengeti Plains

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Here on the Snapshot blogs we seem to concentrate on talking about the animals that populate the Serengeti. Of course these are the subjects of our many camera-trap images (oh, apart from those annoying over grown vegetation ones) and they are loved by us all but for once I thought I would talk about the Serengeti itself. Monitoring the animals that live in the Serengeti is a valuable way to assess the health of the landscape but to get a true idea of the state of play the whole ecosystem needs to be looked at. More and more scientists are realising that a holistic approach is needed to truly understand what makes an ecosystem tick and how to preserve it. Studying lion without looking at their connection to wildebeest and grass is like studying maths by looking at the numbers without the plus or minus signs.

So we have all heard of the Serengeti but what do we really know. It surprises me how many friends don’t actually know what country it is in. The Serengeti National park, where our 225 camera-traps are located is in Northern Tanzania bordering Kenya’s Maasai Mara National park. The two together with the Ngorongoro Conservation Area and other private game reserves make up the Greater Serengeti Ecosystem which protects the area of the great migration. It is easy to see where the confusion comes from.

Everyone has heard of the wildebeest migration but did you know that it is one of the largest animal migrations in the world that has not been drastically altered by humans, there are no barriers to impede the movement of the millions of animals that seek fresh grazing and water. The 1000km circular migration route sees around 500 000 zebra, over 1 million wildebeest followed by hundreds of thousands of other ungulates annually. All this is still able to happen thanks to the protected status of the entire ecosystem.

The Serengeti National Park itself is made up of around 1.5 million hectares of savannah. Flat or undulating plains covered in grasses which are nourished with ashy soils derived from nearby volcanoes dominate the landscape. Rocky out crops known as kopjes punctuate the flatness with infrequent river courses and their riverine habitat easing the monotypic view.

So what triggers the massive ungulate migration and all the inherent predator action? At the onset of the dry season grasses begin to dry out and water becomes scarce, ungulates are forced to follow their nose to find food and water. Luckily nature is well designed and there is a well defined gradient across the migratory path that sees differences in place and time for abiotic factors such as rainfall, temperature and soil type. It is these factors that govern what vegetation grows where and how available water is and of course where the millions of hungry herbivores can move to next to satisfy their needs. Once settled across the Mara River they can last out the dry season in the mixed savannah woodlands where food is not so scarce. But the pull of the plains is always there and with the onset of the rains back they go thundering towards the Serengeti once more in a tradition that has possibly been around for over a million years.

The area is the last remaining example of a large mammal dominated ecosystem that existed across much of Africa during the last 1.8 million years. With its relatively intact biodiversity and sheer size it is easy to see why scientists flock to study both the individual species that occur here and functioning of the ecosystem as a whole. Sadly there are not many places like it left on Earth.

 

Serengeti Field Update

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Snared wildebeest being released

 

June through August is a busy time for scientific researchers. They get to leave their desks and all that computer stuff and go visit their study area. Snapshot Serengeti’s resident researcher Meredith is lucky enough to be in the Serengeti as I write and she has shared a few recent experiences with me.

She is currently setting up a new camera-trap array in Grumeti Reserve which borders the Serengeti National Park in the north west. This area was created as a buffer zone to the Serengeti National Park to help protect the western corridors of the famous wildebeest migration of the Serengeti/Mara ecosystem. Grumeti in turn is bordered by villages and has one of the fastest growing human populations around the Serengeti Park. Traditionally these communities hunted for bushmeat to supplement their diets but with the rise in population it is doubtful if this is still sustainable.

Meredith has been out this week following the migration as it moves along Grumeti’s northern border. As well as setting camera-traps and marvelling at the numbers of wildebeest she has also seen the darker side of conservation that almost anyone working in protected wildlife areas in Africa is familiar with; poaching. She reports that they have been removing snares daily and that distressingly they found 4 snared wildebeest within a half hour, two were dead, one had a broken leg and had to be killed but miraculously they were able to release one.  Whilst trying to select camera-trap spots Meredith and her team encountered poachers butchering a fresh caught wildebeest, they were able to give chase, alas to no avail.

In areas like this the locals know well the movements of the animals and they will seed the area with thousands of wire snares. Anti poaching teams are kept even busier during migration time knowing this too. The anti poaching team, well trained as they are, have had more luck than Meredith and her team. This week they set up an ambush and took out a biltong (dried meat) camp. Their efforts on the front line destroying snares and apprehending poachers as well as the community liaison work that goes on at Grumeti has reaped rewards. Animal numbers are on the rise, the elephant population has quadrupled in the last 11 years and giraffe and topi numbers have tripled.

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Wire snare set along a game trail

 

Still Dr Craig Packer and his colleagues have estimated that tens of thousands of wildebeest are poached each year…and this is not a problem that will go away. You can read more about the issue in this Africa Geographic article.

http://magazine.africageographic.com/weekly/issue-36/serengeti-migration-wildebeest-tanzania-poaching-running-gauntlet/

Poaching goes on all around the world, I have even found wire snares set in my own garden her in France (probably for badger). It is a senseless, lazy but effective way to catch animals. There are many reasons why people poach, when I lived in South Africa the local community would poach our animals not because they were poor and couldn’t afford meat but because warthog and impala meat could fetch higher prices than chicken, goat or pig. Christmas was a particularly bad time for poaching as local chiefs put in their orders. Bushmeat was a delicacy and poaching made good money. In Central African Republic the systematic stripping of wildlife by the Sudanese cattle herders has been stimulated by draught and poverty in Sudan, they dry most of the meat to take back and sell in the Darfur region. Utilising the natural world is deeply rooted in many cultures around the world and always has been. Opportunity is what fuels the practice but it is the rapidly rising human population that is causing this age old practice to become unsustainable in our shrinking world.

I hope Meredith doesn’t have to witness too much more wildlife destruction but all the same it is good for a scientist to get firsthand experience of one of the biggest issues facing wildlife today and for us to recognise it.

Southern Ground Hornbill

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As some of you know, Snapshot Serengeti is not just about mammals. Their avian cousins also like to get in on the act especially the larger ones. Amongst the more common captures are kori bustards, secretary birds, korhaans, and storks. The one I like best though is the ground hornbill.

I fell in love with these birds many years ago when I helped hand raise southern ground hornbill chicks. Although wide spread and fairly common over most of southern and eastern Africa the southern ground hornbill has lost around 70% of its home range in South Africa. They are large birds and don’t do well outside of protected areas especially where human density is high.

Ground hornbills lay two eggs in, believe it or not, a cavity in a tree. The first chick to hatch will kill the second, which is really just an insurance policy in case the first egg doesn’t hatch or should die in the first few days. We were given permission to take the second egg once the first had hatched in order to hand rear then release the birds. The newly hatched chick has to be one of the ugliest babies I have seen. It is a charcoal grey naked greasy looking blob with a head so large it cannot lift it up. For the first day or so it just flops around barely able to raise its bill for food. When its feathers start growing it looks like a diminutive dinosaur. Eventually they do blossom into the splendid giants that strut across the savannahs in small family groups eating a range of food stuffs from insects, rodents and reptiles. They can kill efficiently with that heavy bill and will take anything up to the size of a hare.

Considering their size it is hard to believe that they can fly but fly they do and spend time perched in trees. In fact the loss of large trees is another reason behind their decline, as I said earlier they need trees to nest in. Ground hornbills are cooperative breeders with several family members helping to rear the single chick. This joint effort seems strange until you realise that although they breed once every three years the groups only manage to raise one chick to maturity every 8 to ten years. Once a chick has fledged it is dependent on its parents for two years, which is the longest span of any bird and makes reintroduction programs very hard. It only reaches maturity at 6 years old.

There are two species of ground hornbill, found only in Africa. The southern ground hornbill (Bucorvus leadbeateri) the species found in the Serengeti and the northern ground hornbill (Bucorvus abyssinicus) found across sub-Sahara from Mauritania to Uganda in suitable savannah habitat. The later is slightly smaller than the former and has some blue facial patches which distinguish it from the red of southern ground hornbills.

Such a large bird living mostly on the ground the ground hornbills have not escaped the attention of man. Although many tribes hold totemic beliefs about the birds that afford them some protection others are not so lucky. The Zulus and Xhosa of South Africa believe that to break a drought a dead ground hornbill must be tied down in a streambed to attract rainwater. In a more modern twist ground hornbills, ever territorial will smash windows and car windscreens with their powerful bills in a misguided attempt to evict intruders (namely their reflections) This has not endeared them to humans.

All in all the ground hornbills are magnificent birds, next time you spot one on Snapshot Serengeti take a moment to have a closer look.