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.


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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

The Patels Visit Udawalawe

Guest post by Yogi & Nikita Patel

We traveled to Sri Lanka to work with Trunks & Leaves in support of schools surrounding the Udawalawe National Park. We first arrived in Negombo, Sri Lanka where we were met by Deepani, who works with Trunks & Leaves, and her friend Jocelyn. We traveled by car to Udawalawe where we were joined by Sameera, the project coordinator. We visited the first Montessori preschool, operated by Sameera’s sister, Chathurika. She was gracious in showing us the school, which was closed for the holidays. She had been hard at work painting furniture and cleaning the classroom and play area for her 18 students. Her school, which is attached to her home, is surrounded by many fruit trees. Her family members supported her passion for educating children in her town.

Our next stop was school teacher Shiromi’s home. We met with Shiromi who greeted us with her family and offered the most amazing homecooked treats. We chatted about her work in the village and her school, Dimuthu preschool. We met with Shiromi again the following day, where we observed the children in her classroom. The parents were very supportive of Shiromi and came to the school with their children even though they were supposed to be on holiday. We got to sing and dance the “hokey pokey”.

Deepani, Yogi and Sameera with the first cohort of preschool teachers whose schools received support from Trunks & Leaves’ sponsors (photo courtesy of Yogi Patel).

Continue reading

The Brief Life of [T212]

By SdS & USW

All looks peaceful…

 

…until you look closer.

He looked as though he were sitting down, surrounded by grass and reeds, his back against the intense blue sky, reflected in the mirror of the reservoir. Countless people had passed by, assuming he was just resting as he ate. You could see him easily from the road, just a few tens of meters from the electric fence along park boundary, close to the spillway.

But hours later, when he still hadn’t moved, someone realized something was wrong. Continue reading

Stake-out, Part 1: Where did all the elephants go?

by SdS

A lone male at the reservoir was all we saw…

Back in 2007, 2008 and 2009 UWERP devoted intensive effort to surveying all parts of the park in order to make an estimate of the elephant population. Ten years on, it is time to re-do this exercise. What that means is that for a few specific months each year, we have to try and cover the park more evenly in space and time than we normally do when studying behavior. The trouble was, the elephants were missing. For much of the preceding weeks elephants had been scarce, so much so that guests were leaving annoyed. This was not unusual – I remembered that during the hottest and driest months, elephants usually stayed in the shade until late afternoon even back then. I supposed they were resting and conserving their energy until nightfall. But we could never know for sure. Continue reading

Investing in The Next Generation

By SdS

Students at Kalawelgala elementary school can now learn in peace thanks to the metal grilles installed on the windows, which prevent monkeys and other animals from getting in.

Back in June we held a crowdfunding campaign to support our work with some of the villages bordering Udawalawe National Park and the Wetahirakanda corridor. Thanks to our sponsors, we were able to raise $6000 for improvements at five pre-schools (Montessories) and an elementary school. We re-visited each of the schools in July to confirm their needs. In August it was my pleasure to visit with each of the teachers in order to provide the initial installments of funds. As the schools were on break, we visited several at their homes. Each teacher undertook individual accountability for showing that work was progressing and funds were being spent as intended.

Ms. Lakshimini accepts the sponsorship.

The first stop was with Ms. Lakmini of Pubudu Pre-school. Continue reading

The Folly of Fences

Electric fences that split forested habitat are all too common. As a result, occurrences like this are frequent.

Sri Lanka is part of the ancestral home of Asian elephants and a skeleton traced to this population now serves as the definitive “type” specimen. They existed before settlers colonized and cultivated, before the ancient tanks were built, before the kings and kingdoms, colonizers and governments. This was their land long before humankind set foot on it to set about defining visible and invisible boundaries for ourselves and everything else. Yet here we are, and we are here to stay, so our fates are now linked. An elephant is more than a mere animal or symbol. It is the most un-ignorable occupant of a swiftly vanishing world that harbors an infinitely old and precious natural heritage. It is also a force of nature that annually claims human lives. Therein lies the crux of the difficulty. There’s just one question we need to ask ourselves: do we want elephants (and their bretheren) to persist on this little island, or not? I pose this question on World Elephant day because we are at a juncture that will decide the outcome. Continue reading