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.
Hi guys! Sorry for the long hiatus on my front. Africa was just as exciting and frustrating and marvelous and difficult as I had imagined it would be, and I’m missing it terribly. I made it back to the US just a week or so ago, my suitcases full of lion manes, camera traps, dead telemetry equipment for repair, and several very important hard drives full of new data to analyze! It’s going to be a busy semester synthesizing everything I learned this summer and planning ahead for the next go around.
Coming home from the field for me typically means a week of celebratory eating (ice cream for breakfast! fruits all day every day!), celebratory showering (hot water! running water!), celebratory lavatory use (it flushes!), among other things. This time, though, I’ll have to admit that even these luxuries didn’t soften the blow of leaving.
(Impending statistics classes awaiting me in Minnesota probably didn’t help either).
There is one primary advantage to coming home, the one thing that makes me appreciate every day that I’m back, and it the fact that for a few blissful months, I will no longer have to deal with these little devils:
Good riddance, tsetses! Hello, Minnesota!
The Snapshot Serengeti science team has been a bit remiss at blog posts over the summer. Meredith has been battling tsetses in Serengeti for her first ever Serengeti field season, and I’ve been kept busy traveling on three continents – between finishing my dissertation, crewing for my partner in the world hot air balloon championships, and…moving to Oxford to join the Zooniverse!
We’re still working out exactly what my job title and job description are (details!), but now that the dissertation is officially finished and I’m settling in here, expect more posts to come!
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.
We have just been awarded a second Expedition Council grant from the National Geographic Society to extend Snapshot Serengeti until the end of the year. This covers the end of Season 9.
You, our Snapshot Serengeti volunteers, are the people who make this work possible. Your careful classifications provide the necessary rigor to make Snapshot a truly scientific endeavor, and we also rely on your enthusiasm and insights in highlighting the many interesting, intriguing and unusual photos, which will someday be compiled in articles and books.
The following paragraphs are taken from our successful application, and give an overview of Snapshot Serengeti’s success broadly:
Our large-scale camera trap grid provides a continuous record of the abundance and distribution of herbivores, insectivores and carnivores in the northern 1000-km2 of the long-term Serengeti lion study area. The camera traps provide accurate abundance estimates of 20 different herbivore species across the Serengeti and near-perfect measures of lion numbers in the woodlands portion of our long-term study area. The camera traps also reveal that cheetahs are able to coexist with lions by waiting a minimum of 12 hrs after the lions have departed from a particular site and that lions and hyenas largely come into contact with each other as a result of their mutual attraction to wildebeest and gazelle. Our grid also provides a remarkably detailed portrait of the wildebeest migration, showing how movements vary from year to year in response to annual variations in rainfall. Besides providing novel scientific data, many of the camera-trap images are artistic, captivating, breathtaking and hilarious. Because daytime pictures are taken in sequences of three, they can be combined into a brief animation that make the portraits come alive.
The camera-trap imagery has also provided the foundation for a successful online “citizen-science” initiative, called Snapshot Serengeti, where hundreds of thousands of volunteers have counted and identified the animal species captured in over 4,000,000 photographs. We have developed a series of “consensus criteria” for accepting their species identifications, which have 97% accuracy compared to the assessments of a panel of expert field biologists, and our Snapshot volunteers have developed an active online community who share particularly exciting images.
With funding from the Howard Hughes Medical Institute, we have partnered with the College of Biological Sciences at the University of Minnesota to develop an undergraduate laboratory sequence in “Savanna Ecology” where students read relevant articles from the scientific literature, form hypotheses about the behavior and ecology of a species of particular interest, classify and count animals from a random subset of online camera-trap photos, access the overall database, test predictions with simple statistics and present lab reports in a group setting.
Our pre-proposal to extend the camera-trap project for an additional 3-5 yrs has recently been approved by the National Science Foundation, and we will submit the full proposal at the beginning of August. If funded, we will collaborate with National Geographic to submit a proposal to the educational program at NSF to expand the classroom activities of Snapshot Serengeti to middle- and high-school students around the US.
We have discussed the pictorial potential of SnapshotSerengeti with senior staff at National Geographic, who are interested in featuring a selection of Snapshot highlights in a 2015 article for the Magazine and are also considering publishing the Snapshot photos in either hardcopy or as an e-book. Many of the individual photos are stunningly beautiful, and many more have a unique freshness because the animals have no sense of a human presence. The daytime “triplet” animations live and breathe like pictures in a fantasy novel.
Our first Expedition Council grant covered the first 3 mos of a 15-month gap in NSF funding when our most recent NSF grant ended in September 2013. In addition to the first EC grant of $30,000, we raised $55,000 from an Indiegogo crowd-funding effort. A small NSF grant to support my upcoming sabbatical includes a supplementary $25,000 to cover fieldwork in July, August and September. The $30,000 awarded in the second Expedition Council grant assures continuity of the Serengeti studies until the end of December 2014.
For the upcoming NSF renewal, we have assembled a well-regarded scientific team to study the Serengeti food web by integrating the lion tracking and Snapshot cameras with new measurements of grasses and soils. The approval of our NSF pre-proposal means that we have survived the first 75% cut in grant applications, so we have a reasonably good chance of sustaining the project long term. But even if not successful, the extension of the camera traps for another few months will be extremely valuable, as this will be the first opportunity to measure the wildebeest migration during an active El Nino – rainfall in the Serengeti is highly sensitive to the Southern Oscillation Index (SOI), and the short rains of November-December have largely failed during the past 3-4 yrs of La Nina weather patterns.
So those of you who have read my blogs are probably used to hearing me bemoaning the fact that I am no longer in Africa but am back in France whilst I am studying towards a degree. I can’t really complain, life is still good, but the European wildlife feels a bit lacking when you have been used to the mega fauna of Africa.
I have however continued to put out my camera traps in order to survey my property and the surrounding countryside and it’s busier than you would think. Badgers, foxes, hares, otters, roe deer, squirrels, stone martens and wild boar make regular contact with my paltry two cameras. Not really enough camera power to base a study on but interesting all the same.
The highlight has been the discovery that one little favourite of mine from Africa has followed me to France; the genet. Yes the common genet (Genetta genetta) lives in France and I am ecstatic to say right by my house too.
It seems no-one really knows how they got here but it was probably something to do with the Romans centuries ago being brought over from the Magreb region of North Africa. They are now naturalised animals in Spain, Portugal and France. Refreshingly for an introduced animal they are not invasive and have little impact if any on the native wildlife, so I can go on loving them with a clear conscience.
Here are a couple of shots of genets in France for your enjoyment!
I have to admit that the defense was way easier than I had anticipated. In fact, I got to spend much of the two hour question session talking about possibilities for future citizen science projects and the cool things that could be done with camera trap surveys. Once things settle down on my end, I’m looking forward to sharing some of my most recent results here on this blog.
…But it might be a few weeks. Right now I’m in Brazil, crewing for my boyfriend in the world hot-air balloon championship. We are centered in Rio Clara, and this place is beautiful. Although more cultivated than some of the places we are used to flying (e.g. Serengeti), we have still managed to find some wildlife. When we (the chase vehicle) managed to find the landed balloon past a maze of 12-foot-tall sugar cane fields, the co-pilot looked at me nervously and said, “there are no hyenas in South America….right?” Because apparently they had seen a rather large canid ripping into some carcass on some abandoned hillside on the flight. And it turns out that there are maned wolves here, which is probably what they saw. Maned wolves actually vaguely resemble giant red foxes (~ 3 ft tall at the shoulder), and are in a genus all their own (Chrysocyon), and are considered “vulnerable” (as a species) by the Brazilian government. They are pretty cool.
Funny story. When I was applying to graduate school, long before I decided to work with Craig at the University of Minnesota, I had wanted to study maned wolves in the Brazilian cerrado (tropical savanna). And, in the end, I turned down an offer to do so in favor of coming to UMN. But wouldn’t you know it, 6 years later, here I was – right in the middle of maned-wolf country! Granted, *I* still haven’t seen a maned wolf here, as is usually the case. The balloon pilots, with their birds-eye view, always see the most spectacular things. We on the ground just hear about them.
But I’ve got nearly two more weeks here…and I’m on a mission to find me a maned wolf!
Just a quick update on a room change for the seminar — it will be in Borlaug 365 at 1pm, July 11. The official announcement is below!
PhD Defense Seminar in the
Ecology, Evolution, & Behavior Graduate Program
Advised by: Dr. Craig Packer
1:00 pm, Friday, July 11
365 Borlaug Hall
“Living with lions: spatiotemporal mechanisms of intraguild predator coexistence”
Top predators often suppress their smaller guild members and this can have profound consequences that cascade throughout the larger community. Suppression is mediated primarily through interference competition: direct aggressive interactions and behavioral avoidance by mesopredators to minimize the risk of aggression. These avoidance responses can be costly, especially when they result in large-scale displacement that reduces access of the subordinate species to resources. My dissertation explores the role of behavioral avoidance in driving intraguild predator dynamics, specifically hypothesizing that large-scale displacement drives mesopredator suppression, but that fine-scale avoidance strategies may promote coexistence by minimizing risk without costly large-scale displacement. Specifically, I examine how African lions affect spotted hyenas, cheetahs, and African wild dogs in Serengeti National Park, Tanzania. I first evaluate evidence for mesopredator suppression and large-scale displacement using long-term historical data. I then evaluate patterns of avoidance at fine spatiotemporal scales using novel camera-trapping methods and citizen science. Together, these studies identify large-scale displacement as a key driver of mesopredator suppression and fine-scale avoidance as a key mechanism for mesopredator persistence.
This Friday, July 11, I’ll be defending my dissertation. A little over a week ago, I hit the “send” button that submitted my dissertation to my committee members. At 124 pages, it falls smack-dab in the middle of most EEB (Ecology, Evolution & Behavior) dissertations (as my friend Marcus describes in this cool (albeit nerdy) post here). The defense itself consists of an hour-long presentation (open to the public – so karibu Borlaug 365*, July 11, 1pm) followed by 2 hours of medieval torture – whoops, I mean questioning – by my committee.
The last few days and weeks have been hectic. Since submitting my dissertation, I’ve been focused exclusively on preparing this seminar. An hour is a long time — but still somehow not long enough to talk about everything I’ve been doing for the past 6 years. Hell, I could talk for an hour about Snapshot Serengeti alone! And that’s just a part of my broader dissertation!
I’m excited and nervous and eager to be done with it all at the same time. Summer defenses are always a bit sad, as so many students and faculty are away in the field. Although I’m excited to finish my dissertation, I’m by no means done with Snapshot Serengeti. Not only am I preparing several Snapshot papers for publication, but…drumroll…I’ll also be joining the Zooniverse team in Oxford in the fall. As you probably know, Zooniverse received a Google Global Impact Award to build a generalizable tool so that science teams can build their own citizen science websites. I’ll be joining them on this adventure as their “resident ecologist” — to help make sure that such a tool makes sense for science teams asking questions about the natural world.
So! Exciting times. And hectic times. I will try to keep posting over the next few weeks as I defend (*fingers crossed*), then head to Brazil to crew for my partner in the World Hot-Air Balloon Championships, then pack up the last six years of my life and head across the Atlantic. Lots to come — just have to survive July 11 first…Wish me luck!
* location has changed to Borlaug 365, not 335!