Meredith: Our brilliant team of Snapshot Serengeti undergraduate volunteers at the University of Minnesota are perhaps even more on top of the lion literature than I am! This week, we have a guest post from one such student, Clayton Mazur, describing some recent work of Dr. Packer’s on lion disease spread in Serengeti Park. This post is a synopsis of a scientific paper that can be accessed in full here.
I propose we play a word-association game. I will offer a word and you think of what comes to mind. “Africa.” Did you imagine Mt. Kilimanjaro, or the towering, lush rain-forests of the Congo? “Wildlife.” Did you envision the sprawling savannas of Tanzania, home to hundreds of thousands of migrating wildebeest? If so, I would bet that your savanna also included the enigma of Africa: the African lion. Was he a graceful figure standing upon Pride Rock looking out over his kingdom? Perhaps he was laying in the shade, his dark mane flowing in the breeze as he waits for the females to return with a kill. I would argue that elegant images such as these are what come to mind for the majority the public. The portrayals of lions in the media- from Lion King to the MGM Lion- support this notion. As elegant as these images are, reality is less than elegant for the lions living in Serengeti National Park in Tanzania, Africa.
African lions have unique social structures that help them brave the tough conditions of the savanna. Lions live in families called prides; one to two male lions rule a pride. The roles of female and male lions within a single pride are vastly different. While females hunt, raise the cubs, and reproduce, male lions defend the pride from attack by other predators such as hyenas. Living in a large family group offers lions protection, but it also comes with costs. One cost is that females need to supply a large number of individuals with enough food for survival. Female lions coordinate hunts whereby they stalk prey and then give chase, but this technique only yields about 26% success. The low success rate forces large prides to split or starve. Perhaps a more interesting difficulty of living in a large pride is the spread of disease within lion populations. As Dr. Craig Packer has found, disease prevalence is a threat to the current lion population.
A fatal disease that persists in the carnivores of Serengeti National Park is Canine Distemper Virus (CDV). CDV infects a range of carnivores, from dolphins to rodents and even some primates. The viral infection causes encephalitis, pneumonia, anorexia and eventually, death. You may be familiar with CDV if you own a dog, for many owners in the US vaccinate their dogs for CDV. In Serengeti National Park, where local villages cannot afford to vaccinate their dogs, CDV is a conservation concern for African Lions who contract CDV from domestic dogs. To try to remedy the concern, an intense vaccination regime started in 2003. Packer and colleagues attempted to characterize the progression of CDV in both domestic dogs and African Lions. Their goal was to determine if domestic dogs were responsible for the infections observed in African Lions. The team also wanted to determine if the 2003 vaccination program had any effect at reducing CDV in the domestic dogs and/or African Lions.
The scientists worked with blood plasma collected from both domestic dogs (obtained from 1992-2012) and from African lions (obtained from 1984-2012). After collecting the blood samples, the team ran serological tests to detect for the presence of the CDV virus in individual dogs or lions. Using a Bayesian model, the scientists then calculated the probability that an individual lion or dog would contract CDV in one year. The scientists also used sensitivity models to determine the extent at which domestic dogs transmit CDV to lions. From the results of these models, the scientists were able to comment on the fate of the lions with regard to CDV.
The research team drew results by interpretation of the two models. They found that CDV had persisted in the populations of both dogs and lions for more than 25 years. Outbreaks of CDV occurred in 1981, possibly in 1976, and in 1993. Not only do these results suggest a historic presence of the fatal disease in the national park, the dynamics of each outbreak of the disease was unique. The scientists found that the year in which CDV infected the most dogs differed from the year in which CDV infected the most lions. The researchers proposed that this pattern identified domestic dogs as initial vectors for CDV in the park. After a 1994 outbreak in the lion population, the dynamics of the outbreaks become more disjoint. The disjointed dynamics between the domestic dog and lion populations suggest that after 1994, infections cycled through the dog population and the lion population separately. However, the spread of CDV between dogs and lions was not eliminated after 1994.
With domestic dogs established as an initial vector of CDV, the scientists wanted to know transmission rates between domestic dogs and lions. Again, they used a sensitivity model to predict this factor. The scientists found that domestic dogs were ten times more likely to spread CDV to lions than lions were to spread CDV to domestic dogs. With such a high prevalence of CDV in the domestic dog population and the tendency for CDV to spread from dog to lion, the effects of the 2003 vaccination effort were an important factor to analyze for the conservation of the Serengeti National Park lions. The scientists first analyzed the effects of the vaccine on the domestic dog population. Before 2003, there had been very sparse vaccination in villages surrounding Serengeti National Park. As was expected, this vaccination effort did little to curb CDV infection in either lions or domestic dogs. It was not until after 2003 when all villages to the east of Serengeti National Park and all villages within 10 km to the west of Serengeti National Park vaccinated their dogs against CDV did there exist a decrease (~5%) in CDV infections.
With CDV slightly decreased in domestic dogs due to the vaccination effort, was there a similar decrease in CDV infections in the lion populations? Unfortunately, the sample size of lion serum that the scientists could obtain was not enough to comment on the updated magnitude of dog-lion CDV transmission. Overall, the scientists determined that CDV was still able to cycle in the lion population with very little reduction in the prevalence of the disease. However, not all is hopeless for the lion populations of Serengeti National Park. Dr. Packer’s team suggests that direct vaccination of lions may be more effective at preventing the disease. Additionally, the team suggests that advances in serological techniques would allow for increased accuracy when researching episodic diseases, such as CDV. Implementation of safe vaccines coupled with more accurate serological tests could minimize the effects of CDV outbreaks and ensure the health of the Serengeti lions.
As evident from the work of Dr. Packer and colleagues, there are threats to the conservation of the lion populations of Serengeti National Park. Not only do prides run the risk of individuals starving to death, splitting, and human-lion conflict, disease is another risk factor of living in a pride. Yet, these prides, these perfect families, come to mind when the public thinks about lions. Idealistic images of cubs play fighting or suckling from their mother are important for generating interest and compassion for African lions. One can be content with the image of the brave, courageous, elegant male lion standing on Pride Rock overlooking his kingdom, but one must simultaneously recognize the reality of the lion’s plight. Only then will conservation for lions be truly feasible.
Meredith: Not all of our exciting research takes place in the field — there’s a lot going on behind the scenes in our lab, and we rely on an invaluable group of undergraduate research assistants to help us go through the massive amounts of Snapshot data you guys provide! Jess has been working with us for the last few semesters and has some insight on what it’s like to work with this Serengeti data set.
Hello everyone! My name is Jessica Dewey, and I am currently an undergraduate student at the University of Minnesota working in the research lab that runs this project! Cool, right? I’m new around here so I thought my first post should be an introduction of myself and how I got involved in this lab.
Imagine me a few years ago: a young high school student, undoubtedly procrastinating in some way, suddenly stumbling upon a website called “Snapshot Serengeti”. At the time, I was only certain of two things — I loved animals and I loved research – so this discovery was perfect for me! I spent most of my evening identifying animals, and continued to go back to procrastinate even more.
Now flash forward to last semester, when I get an email from one of the university biology clubs saying that Dr. Craig Packer, head of the Serengeti Lion Project, will be giving a talk about his work. Well I HAVE to go! I sit and listen intently, eager to learn all about research being done with lions. Near the end of his talk he then mentions a website (Snapshot Serengeti, of course) where all of the images from the field get uploaded for the public to identify, and I’m immediately floored. How did I get so lucky, to go to the very University that uses those pictures I spent time identifying years ago in their research? The best moment was when the graduate students working with Craig said that they were looking for undergraduates to help them with their research. I took the opportunity to introduce myself to Meredith, and so far my experience in this lab has been amazing.
I’ve learned a lot about how field research is done, how data is collected and analyzed, and what it takes for someone to actually be a researcher in the field. Not everything I do is as fun as going through tons of pictures a day, but all of the work in this lab is interesting and meaningful, and that’s what really matters to me. One of the major projects the lab has been working on with Meredith is trying to characterize changes in habitat at the camera trap sites by looking at the Snapshot pictures. We have been going through the giant list of data to find pictures to use for this characterization. We haven’t been going through the images themselves – rather the metadata, or the data ABOUT the data (it’s literally the biggest Excel sheet I’ve ever seen). It can get monotonous at times, but what keeps me going is the thought that when we finish picking out all of these random images, we will get to look at them and use them for this research project.
I hope that was a thorough enough introduction for you all, but let me say one last thing: THANK YOU! Without the time you all put in to identifying these pictures, the research we are doing would not be happening at the pace it is.
Here is one of my favorite images I’ve seen so far:
We’re partnering with National Geographic to put together a photo book of animal selfies from Snapshot Serengeti. We’ve got some selfies already from the first seven seasons, but because no one has looked through Season 8 yet, we don’t know what great selfies might be in there.
You can help! If you find an animal selfie, please tag it as #selfie in Talk. (Click the ‘Discuss’ button after you’ve classified the image and then enter #selfie below the image on the Talk page. You can get back to classifying using the button in the upper right.)
All proceeds from book sales will go to supporting Snapshot Serengeti. We’re planning for a fall 2016 publication date, so it will be a while. But we’re excited to get working on it.
Looks like everyone is sinking their teeth into Season 8! As a reminder, feel free to ask questions or chat with us through the Snapshot Serengeti Discussion board or in the comments of any of our blog posts.
Now, there’s some data from this new season that hasn’t made it online — sometimes, instead of taking pictures, our cameras accidentally switch into “video” mode and capture 10-second clips of animals doing their Serengeti thing. While this isn’t very good for us in terms of data collection (although we’ve been tossing around the idea of setting up a Snapshot Serengeti: Video Edition!…), it gives you a unique perspective on the lives of these animals.
(Okay, so it’s mostly animals eating grass. They eat a lot of grass. Perhaps not the most “unique” insight on their behaviors, but they’re still pretty fun to watch). Here’s some of my favorite accidental movies from our new Season!
The Minnesota winter has finally come upon us and time is passing exasperatingly slowly, waiting to hear back from funding sources, plowing through homework, cleaning up data, and mostly daydreaming about heading back to Serengeti. Perhaps the dread of spending the next semester in the cold is stirring undergraduates into action, but I’ve been contacted by numerous students recently inquiring about something near and dear to my heart: field experience and how to get it.
Field work is what makes biology for me – I don’t think I could get by without that glimmer of hope, the promise of going out and getting dirty and experiencing ecology in the raw. The summers of my own undergraduate career and the two years before I entered graduate school were spent almost entirely out in the bush: measuring fishes and catching snakes and doing pretty much whatever kind of work I could come across that would let me mess around doing science in the great outdoors.
I lived for that work, but I can’t claim that it’s entirely glamorous. You won’t be picking up a brand new Ferrari any time soon, that’s for sure. My first field jobs could barely be called sustenance living, but after a few years of experience, I was picking up jobs that came with fancy, real-person benefits (oooh, like Dental).
And then there’s that whole “in the field” thing to consider — in all its glorious, treacherous, beautiful and exhausting majesty. I’ve been on field jobs where people have suffered through dengue and malaria, contracted parasites, twisted limbs, narrowly avoided encounters with venous snakes (on an almost daily basis), and quite literally passed out from exhaustion in the middle of the wilderness. “Sweat, blood, and tears” sums it up quite nicely. You’re stuck with the same old crew for weeks, or even months, on end, often with limited amenities. If isolation is not your thing, perhaps second thoughts may be in order. Also take into account the facilities you’ll be living in. I’ve been overwhelmed by the relative “luxury” of some field stations (electricity! food that isn’t rice and beans!), and enjoyed the struggle of situations at the opposite end of the spectrum (cold showers are good for you, and you didn’t need to check that Facebook this month anyway…).
Which isn’t to sell any aspect of fieldwork short. Doing fieldwork is an absolutely wonderful way to get your butt outdoors, see the world, enjoy nature, and it does wonders preparing you for a career in science. Techniques I’ve learned and people I’ve met along the way have been invaluable when it came to getting new jobs and heading back to school. I feel far more prepared to do my own research after having participated in such a diversity of projects. Plus, you get to be your down David Attenborough and live the things you’ve only ever seen on Nature documentaries or in the zoo. It’s a well worth-while experience.
So, the important part: where to find the job.
For those still in an undergrad program looking for a summer position, the NSF Research Experiences for Undergraduates (REUs) are definitely the first place to hit up (NSF REU; NSF for BIOLOGY). These are great paying positions that are geared specifically towards getting you involved in your own research. I completed two REUs during my undergrad, spending one summer working in Panama studying developmental plasticity in Red-eyed tree frogs and another on the island of Puerto Rico filming the territorial behaviors of Anolis lizards. These experiences are wonderful because you are highly involved with the lab you work in, you get to meet and interact with a large body of scientists from various disciplines, and if you’re designing your own project, get invaluable input into the process of constructing an experiment. For me, both of my REU projects resulted in publications – an important factor for applying for graduate school.
List servs are beautiful, beautiful things, because job applications find their own way into your inbox and sit there waiting for you to read them. They’re also a great place to join in on scientific discussion and share ideas, articles, and even research equipment. Some of my favorite list-servs are:
- ECOLOG-L: Run by the Ecological Society of America
- MARMAM: For researchers working with marine mammals
- MAMMAL-L: I believe this was set up by the American Society of Mammologists?
You can probably tell that I’m a bit biased towards mammal work, but ECOLOG runs job advertisements from everything ranging from forest ecology to herps and fishes through to hyena biology in Kenya.
Biology job boards are the next place I turn when looking for the next field position. These update fairly regularly, so keep checking up on them:
- Texas A&M biology: My absolute favorite – there are some really fantastic research opportunities that make their way to the Texas A&M job board
- ConBio: Run by the Society for Conservation Biology
- Primates: For those interested specifically in primates
- AZA (Zoos): If the field isn’t quite for you, but you’re still gung ho about working with animals, be sure to check out what’s going on at the zoos
- USAjobs: Government jobs are some of the better-paying gigs in the biology business
Find the job applications is, like most things in life, just the first step in a Process. Next come the cover letters, the applications themselves, scrounging up enough references and actually getting them to submit letters for you on time (often, the most difficult part). But hopefully this provides as starting point for those ready to get out there and do some science.
Just for fun. I was hanging around on Talk today and stumbled across this grooving Kori Bustard. Kind of makes me want to dance…
Cheetahs, it seems, just can’t stop shattering everything we believed to be true about them.
Scientists have long believed that lions (and hyenas to some extent) threaten cheetah conservation efforts — in large part because they kill so many cheetah cubs. But last year, researchers from South Africa revealed that lions probably don’t kill as many cheetah cubs as folks previously believed. And shortly after that, our research showed that regardless of the amount of lion-inflicted cheetah cub mortality, cheetahs do just fine around large lion populations.
Just last month, another story broke that shakes up how we think about cheetahs. It turns out that not only are cheetahs not as vulnerable to killing by lions, but they cheetahs aren’t nearly as vulnerable to non-lethal bullying either. It was thought that because cheetahs couldn’t fight back against lions – or hyenas – they lost a lot of their hard-earned kills to these ruthless scavengers. (Yes, both lions and hyenas do steal food from each other and from cheetahs.) We knew that wild dogs expend so much energy hunting that they can’t afford to lose even moderate levels of food, and assumed that cheetahs were similarly vulnerable. But, as a recent study from Bostwana and South Africa found out, they aren’t. It turns out that despite being super fast, cheetahs don’t expend all that much energy chasing down their prey. Researchers estimate that cheetahs could lose a full 50% of their kills to lions and hyenas, and still get all the calories they need!
All in all, it’s beginning to look a lot like the biggest threats to cheetahs aren’t lions and hyenas. Instead, availability of denning sites (as suggested by our research) and human destruction of habitat that forces cheetahs to travel far and wide in search of prey (suggested by this most recent study) are probably much, much greater threats to their survival.
One of our long-time Snapshot Serengeti members (thanks Reid!) sent me this NY Times article on African wild dogs. As you know, we don’t have wild dogs in the study area (though keep your eyes peeled! TANAPA did reintroduce them into the western corridor the other year, and I keep hoping we’ll catch one traveling through our grid).
But I am very interested in how dogs interact with the larger carnivore community. And these animals are just *so* cool – incredibly energetic and full of nerve. Watching a small group of dogs defend their kill against a hunting party of hyenas was one of the highlights of my trip to South Africa in June.
The article points out that wild dogs may fare better when lions fare worse (which I’ve reported on here) — and that raises some questions about questions about how to target conservation efforts. Do we have to choose between which species to protect? I’d say “not necessarily.” My dissertation research suggests that although dogs fare worse in small reserves with lions, there are places where wild dogs seem to do just fine. Selous Game Reserve (TZ) and Kruger National Park (SA), for example – big areas that have complex habitat structures. So the answer to protecting the entire carnivore guild may lie in larger, diverse reserves.
There are currently efforts in place to do create a protected area the size of Sweden that spans five southern & east African countries. If successful, according to the NY Times, the Kavango-Zambezi Transfrontier Conservation Area will be the largest terrestrial protected area in the world. Now that’s something to celebrate.
I am sure you were all enthralled by the recent shots of a male lion with a hyena clamped in his jaw. A truly awesome capture. The reality is that action shots like that are few and far between. Snapshot Serengeti has had only a handful in the millions of images that have been classified to date.
So when Karen and Deon Scheepers caught the following action on camera trap on the nature reserve in South Africa where I used to live I just had to share it with you;
What a capture… a leopard on the hunt. The out come was unknown, reserve staff looked for a carcass but didn’t find anything. To think I used to walk those trails every day, I wonder how many times a leopard walked out behind me!
Thanks Karen and Deon Scheepers for sharing these shots.