E is for “Endangered”

Or why we shouldn’t take those large odd-looking animals for granted.

E is for Endangered

Step into any nursery or play room, take a quick walk down the isles of your local bookstore or library. Or just look at the clothing and toys we surround children with. They are full of images of iconic animals – giraffes, rhinoceros, hippos, lions, elephants…

We use these animals to teach the alphabet, and cherish them as beloved characters in our story books. They adorn everything from birthday cards to blankets.

What would the world be like without them?

Last week the IPBES released a monster report detailing how biodiversity today is threatened by human activities. A splashy number that grabbed a lot of headlines – at least ONE MILLION species are at risk of extinction in coming decades through human activities.

But actually, elephants might not be among them. Good news?

Unfortunately, not if you dig deeper.

Traditionally, a species’ risk of extinction is determined by modelling how likely populations are drop below a certain number within a policy-relevant time frame, say 100 years. The trouble is that elephants and many other iconic large-bodied species can live a long time (if they aren’t hunted), and breed relatively slowly.  While this can make them extremely vulnerable and sensitive to disturbances, the effects need not be visible for a long. LONG. Time.

That means we may fail to recognize that some animal populations are in trouble if we only rely on their risk of extinction.

In a study just published in the journal Frontiers in Ecology & Evolution, we argue that for long-lived slow-breeding species, we need a better way of assessing their vulnerabilities. We propose the concept of a “demographic safe space” based on the idea that there are few crucial biological variables (birth and death rates) that govern whether populations are growing or declining. When these rates are healthy, populations are within the boundaries of the safe space. When they are not, it is a call to action. They key is to measure those variables, also known as vital rates, in the wild.

Elephants are good example of this.

Our long term study at Udawalawe showed that most females typically have just one calf every six years or more, and that they have about a 5% chance of dying even after reaching adulthood. They also mature slowly, typically breeding at around 13 years of age. Contrast this with a species like tigers, in which females are capable of reproducing within just a few years and can produce litters of several kittens per year.

Only around 1.5% of Asian elephants have tusks, all of which are male. Habitat loss, poaching for skins, parts and capture of live animals are leading threats, alongside accidents and human-elephant conflict. Healthy females and calves are keys to the survival of elephant populations.


Through a series of simulations, we tested how threats like habitat loss and hunting could affect elephant populations. Our new study shows that elephants are extremely sensitive to changes in birth rates and the mortality rates of females and calves. In the best case scenario, they can tolerate no more than a death rate of 8% among adult females. Male mortality, on the other hand, has very little effect because only a few males are required as breeders. But even populations that are in decline may not go extinct right away if they are large – it’s more like a slow-motion train wreck that happens over hundreds of years. In smaller populations the effects are more dramatic

The study highlights a little-appreciated fact: the biggest threat to Asian elephants is habitat loss, followed by illegal trade in live animals and body parts (see here and here).  The demographic consequences may be hidden, and take a long time coming but they can be insidious. Many elephant populations in Asia are already so fragmented that they number in the tens or hundreds. The way to recover these populations is to focus on improving the survival of females and calves, as well as their breeding rates, To do that, we need to address issues like land-use change alongside illegal trafficking. Conservation efforts also need to place much greater emphasis on the distinct populations that constitute a species, and whether they are healthy, than on ballpark estimates of how many individuals of the species there are throughout their range. The idea of “demographic safe space” helps to identify which populations are healthy, and which ones aren’t.

The data for this paper come from just a handful of studies – for most elephant populations, we have no idea whether they are within their demographic safety limits. Indeed, we don’t know if this is the case for many of slow-breeding iconic species, especially those large enough to be called “megafauna,” and many of which are herbivores like elephants. Think: Giraffes, Rhinos, Hippos. This paper urges that we are desperately in need of assessments for these threatened species, before the demographic train plunges off an unseen cliff.

Demographic inertia is like a train – very hard to reverse course once it gets going downhill.

There is good news here though – by measuring and identifying the vital rates that are most in need of improvement, we hope that the wildlife managers, conservationists, policy makers and the public can rally together in time to save these beloved species.


Call Combinations Differ Among Living Elephants

The living elephants – Asian elephat, African forest elephant and African savannah elephant.

Guest post by Michael Pardo

Ask most people what sound an elephant makes and they are likely to think of a trumpet. In reality though, elephants produce an incredible variety of different vocalizations. The most common call is a deep, pulsating rumble, so low-pitched that human observers sometimes feel it more than hear it. Elephants also roar—powerful, bellowing sounds that carry across the landscape. And sometimes, they give combination calls, in which one or two rumbles and roars are stitched together with no pause for breath.

I visited Udawalawe in 2014 to work with the Udawalawe Elephant Research Project, and was especially fascinated by these combination calls. Combining meaningful units into sequences with an additional meaning is a key component of human language, but there are relatively few examples of this phenomenon in other species. Listening to the Udawalawe elephants, I was struck by the fact that they nearly always produced combination calls in the same order: a single roar followed by a single rumble. Why was this? Could it be analogous to grammatical rules in human language? Or could it be as simple as an anatomical constraint that made it difficult for the elephants to produce a rumble before a roar? Continue reading

Dwarf elephant battles musth male!

16 June 2014 – S. de Silva

Battle1A clear sunny day, Lucy and Mickey are off in the park with Sameera while Kumara and I stay behind to catch up on office work. It’s mid-morning when Sameera calls to tell us Walawe Kota is back!  Walawe Kota is the nickname we’ve given the dwarf elephant of Uda Walawe.  This would be at least the third year now. What’s more, he’s in musth and reportedly fighting another male.  At first, the news is a bit confusing – there’s mention of a possible injury.

I’ve never seen him in the flesh though Kumara and Sameera have. I’ve only seen pictures and video clips, so I’m eager to try our luck. The park office reports he’s been spotted not far from the entrance, so we hop in our Jeep and dash off in hopes he’s still out in the open. Continue reading

How does empathy help elephants?

By S. de Silva

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A small family of elephants in Uda Walawe wanders upon a dead calf which does not belong to them. Yet they show great interest, touching and hovering over the body for hours, refusing to let any observers near until they finally decide to move off. Photos: UWERP

In the past week a paper on reassurance behavior in elephants by Plotnik et al. in PeerJ has been generating quite a bit of buzz. The study, which you can learn more about from the researchers themselves here, collected a series of observations on a group of captive elephants in Thailand documenting how they reacted when one of their companions was distressed.  It showed that when some individuals were disturbed in some way and expressed their distress, other individuals approached them and interacted in ways (such as touching, vocalizing) that suggested that they might be trying to comfort or console their companion.  Such behavior would indicate that elephants have the capacity for empathy, along with a handful of other species.

The title of this post is meant to work on at least two levels. First, we might wonder at a biological level – what is the function of the curious  behavior elephants sometimes show toward others in distress? Why might it have evolved? Whom does it benefit? Second, we might wonder at a practical level – should the capacities of elephants endow them with additional conservation value? Should it matter on the ground? So today, the first ever World Wildlife Day, I’d like to examine these two sets of questions, which are very distinct. Continue reading

Thinking like elephants

By: Lisa Barrett, Research Assistant – Think Elephants International, Inc.
Photos: Elise Gilchrist (c) 2014, Think Elephants International, Inc. www.thinkelephants.org

Plotnik3Think Science. Think Education. Think Elephants. That’s our motto at Think Elephants International (TEI), a nonprofit based in northern Thailand.  Founded by Dr. Joshua Plotnik in 2010, TEI’s aim is to conserve wild Asian elephants in Thailand by integrating elephant intelligence research with conservation education programming. We “think elephants” both because we think of elephants when we consider ways to help improve their conservation status, and we also think like elephants in designing our research paradigms. We use scientific research to understand how elephants “see” their world and how we can most effectively save their world. Dr. Plotnik has shown that elephants are both able to pass the mirror self-recognition task (Plotnik et al. 2006) and that they can cooperate together to complete a novel problem (Plotnik et al. 2011). In addition to demonstrating the amazing cognitive abilities of this species, we are also passionate about research that can directly impact conservation techniques to mitigate human-elephant conflict. Continue reading

Six year update on the Uda Walawe elephants

The Uda Walawe Elephant Research Project is now approaching eight years, a unique study of Asian elephants.  Because elephants are such long-lived animals, it takes a long time to understand them – particularly for important variables like who reproduces and how often.  Studies of wild African elephants have been conducted at multiple sites over 10 years or more (in some cases as many as 40!), but this has not been the case for the Asian species in the wild. There have been long-term records of Asian elephants  populations in captivity from places like Myanmar, where they have long been used in timber camps, and it’s interesting to see how the two compare.

This past December we published a comprehensive paper analyzing six years of data on the wild Asian elephants of Uda Walawe National Park, Sri Lanka. This paper is one of a kind as it has been difficult for researchers to successfully monitor wild Asian elephants due to the difficulty of their habitats, and the logistical challenges of conducting steady research over longer time periods.

Tailless was one of the venerable elders of our population. She was especially important for this study for two reasons: she was unmistakable even after dying due to her uniquely broken tail, and her jaw was recoverable. The wear on her teeth showed her age to be around 60 or more, meaning female elephants in Uda Walawe can potentially live out their full lifespans.

Tailless was one of the venerable elders of our population. She was especially important for this study for two reasons: she was unmistakable even after dying due to her uniquely broken tail, and her skull and jaw were recoverable. The wear on her teeth showed her age to be around 60 or more, meaning female elephants in Uda Walawe can potentially live out their full lifespans. We aged other females in the population relative to Tailless.

Continue reading

EARS ID Database released


We are pleased to release EARS (Elephant Attribute Recording System), designed by intern Ilja Van Braeckel. EARS is an MS Access database that permits quick searching of elephant ID photos. Users enter new ID features using a simple Excel worksheet which can be copied directly into Access. They can then query the database with a set of check-boxes for prominent natural features of individuals, which returns matching IDs and photos.  This should narrow the search substantially and cut down search time.  We recommend that a separate set of high-resolution ID photo files are maintained in parallel at another location and that once the search is narrowed final identifications are confirmed using these external files. The idea is for the database to aid, not replace, more detailed photos and human memory.

We share this tool freely hoping it will help others conduct individual-based studies of Asian elephants, and modifications may be made as required. Variations of it may also be useful for other species and contexts.

The database, excel sheet and a user manual can be found at:


de Silva S, Webber CE, Weerathunga US, Pushpakumara TV, Weerakoon DK, et al. (2013) Demographic Variables for Wild Asian Elephants Using Longitudinal Observations. PLoS ONE 8(12): e82788. doi:10.1371/journal.pone.0082788