Journal of Threatened Taxa |
www.threatenedtaxa.org | 26 December 2021 | 13(14): 20249–20252
ISSN 0974-7907 (Online) | ISSN 0974-7893
(Print)
https://doi.org/10.11609/jott.7620.13.14.20249-20252
#7620 | Received 18 August 2021 | Final
received 05 October 2021 | Finally accepted 27 November 2021
Wildlife managers ignore previous
knowledge at great risk: the case of Rivaldo, the
iconic wild Asian Elephant Elephas maximus L. of the Sigur
Region, Nilgiri Biosphere Reserve, India
Jean-Philippe Puyravaud
1 & Priya
Davidar 2
1,2 Sigur Nature Trust, Chadapatti, Mavinhalla, Masinagudi PO, Nilgiris, Tamil
Nadu 643223, India.
1 jp.puyravaud@mailo.com
(corresponding author), 2 pdavidar@gmail.com
Editor: Heidi Riddle, Riddle’s Elephant
and Wildlife Sanctuary, Arkansas, USA. Date of
publication: 26 December 2021 (online & print)
Citation: Puyravaud,
J-P. & P. Davidar (2021). Wildlife managers ignore previous
knowledge at great risk: the case of Rivaldo, the
iconic wild Asian Elephant Elephas maximus L. of the Sigur
Region, Nilgiri Biosphere Reserve, India. Journal of Threatened Taxa 13(14): 20249–20252. https://doi.org/10.11609/jott.7620.13.14.20249-20252
Copyright: © Puyravaud
& Davidar 2021. Creative Commons Attribution
4.0 International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by providing adequate credit to the
author(s) and the source of publication.
Funding: None.
Competing interests: The authors
declare no competing interests.
Acknowledgements: We thank Ms. Divya
Chaudhry for her support. We also thank an anonymous reviewer for his/her
comments.
Abstract: Management of wildlife depends
mostly on scientific data; ignoring this can lead to unintended consequences.
We take the case study of the wild male Asian Elephant Rivaldo
of the Sigur Region, who was translocated out of his
range. Rivaldo
returned to his home range within a few days, which could have been expected if
scientific publications had been consulted. We suggest that a simple checklist
of relevant publications can help park managers to decide on a proper
management procedure. We also used a simple Bayesian framework to visually show
how the probability of predicting a management outcome is increased by prior
knowledge. The expensive and risky effort to relocate the elephant could have
been avoided altogether if prior knowledge had been taken into consideration.
Keywords: Asian Elephant, rehabilitation,
translocation.
In wildlife management, as
anywhere else, decisions need to be taken for which the outcome is uncertain.
“Uncertain” however, should not necessarily be understood as “unpredictable”. A
typical unpredictable random event is the outcome of tossing an unbiased coin.
No knowledge can help predict whether the coin will fall on its head or its
tail. A typical uncertain random event is the outcome of tossing a biased coin.
By the knowledge acquired that the coin is heavier on one side, it is possible
to predict with some amount of confidence that the coin will fall on its head
or on its tail. Ignoring knowledge with uncertain events can have disastrous
consequences.
Managing wildlife is more complicated
than tossing coins but a management plan is based on objectives that are often
uncertain. Recently, the Tamil Nadu Forest Department and wildlife experts had
to decide whether to translocate an Asian Elephant called Rivaldo.
The success of any elephant translocation certainly depends on many variables
managers cannot control, including the elephant’s preferences.
Rivaldo (Image 1) is a 35–40 year old
male elephant from the Sigur Region (Figure 1) which
forms the buffer zone of Mudumalai Tiger Reserve in
the Western Ghats of India. Rivaldo became habituated
to human food, partly because he was fed with fruits and sugarcane while being
treated for his injuries. However, it was shown that he could be gradually
de-habituated if the feeding were to stop (Puyravaud
et al. 2016). His familiarity with people and inherent docility made him
approachable and a willing recipient of treats from humans, many of whom
utilized this opportunity to make easy money by displaying him to tourists.
This encouraged Rivaldo to beg from tourists and
villagers. In 2020, he entered the gated community of recent settlers and a
narrative was built according to which the elephant needed rehabilitation in
the Theppakadu elephant camp due to some non-existent
disability.
The Mudumalai
Tiger Reserve authorities ordered Rivaldo’s capture,
not inquiring with those who knew the elephant well. They also rejected the
possibility of rehabilitation (Davidar et al. 2021)
proposed as early as March 2020. The elephant was lured into a kraal (a
restraint area) in early May 2021 and kept there for approximately three
months. The newly appointed chief wildlife warden, however, reviewed the case
in July 2021 and concluded that the capture was not based on solid grounds. He
rightly ordered the elephant’s release.
As Rivaldo
was in the kraal, releasing him had to be done cautiously and several options
were available, but translocation was preferred. We don’t really know why
translocation was chosen but we imagine that the aim of this option was to assess
whether the elephant would settle down in another habitat far from where he was
being fed. By this measure, a long rehabilitation program could be avoided and Rivaldo’s problem forgotten. If this was correct, then we
can say for the sake of this paper that the management objective was: “Rivaldo will not come back to his original range in less
than a week”. This objective is sort of a gamble over an uncertain event,
depending a lot upon the individual animal’s inclinations.
The likelihood for managers to
predict correctly the outcome of a project increases with a fair review of
published scientific literature. This generally suffices to get a good sense of
what may be expected. In this instance, translocation is a difficult choice
because it is expensive and increases the risk of mortality of the target
animal (Fernando et al. 2012). Moreover, elephants have home ranges (Baskaran
et al. 2018a), are highly social (De Silva & Wittemyer
2012), and prefer certain habitats (Baskaran et al. 2018b). Furthermore, mature
adult male elephants translocated out of their original protected area tend to
return to their home range, often hundreds of kilometers
away, whereas young adult elephants tend to wander or settle in their new home
(Fernando et al. 2012). With a simple list of publications (Table 1), managers
can easily get an idea about the appropriateness of a plan. In this instance,
published literature did not weigh in favor of
translocation.
In order to maintain objectivity,
managers must remember that results published in scientific journals can be
open to criticism, but are fairly solid. They represent an excellent basis upon
which to argue in favor of or against a given course
of action. Reports such as the Right of Passage (Menon et al. 2005) and its
sequel which are well-known among elephant specialists did not go through the
rigorous peer-reviewed methodological assessment of scientific papers. In
consequence, in spite of their wide recognition, such reports cannot be
considered on par with peer-reviewed manuscripts. Lastly, expert opinion is
probably less reliable than reports and should be accepted only if absolutely
nothing published exists on the matter. Managers should also remember that they
will have to deal with the consequences of their decisions when their expert
advisors have gone back to the comfort of their academic abstractions.
Consequently, we cannot stress enough the importance of published scientific
evidence.
Taking wagers on management
objectives or hypotheses can actually be described with statistics. It is not
necessary to use statistics while reviewing scientific literature as we did
above. Our purpose here is just to show that accumulation of knowledge
increases the chance of taking an appropriate decision. The “chance”
distribution can be powerfully depicted with Bayesian statistics, a branch of
statistics that has become mainstream in conservation and ecology. These
techniques make statistical abstractions such as accumulation of knowledge
tangible and comprehensible with simple graphs. In the following, we attempt to
develop an intuition using techniques that are well described in Donovan &
Mickey (2019).
Bayesian statistics call “Prior”
the statistical knowledge about a phenomenon before an experiment, and
“Posterior” the new statistical knowledge transformed by an experiment. If we
don’t know what an elephant might do after translocation, it is the same as
saying that it can come back after one week or not with equal chances. The
Prior in this case is a flat line (Prior 1, Figure 2). The chance or
probability distribution indicates that anything is possible. But if we take
into consideration only one of the papers referring to translocation cited
above, for example the fact that elephants are attached to a range, then the
Prior is transformed. The Prior 2 (Figure 2) shows that we have a weak “belief”
(the strength of evidence) that Rivaldo might come
back in a week’s time and its curve shows that there is a fair chance that he
will not come back. Taking into consideration other published papers, Prior 3
and Prior 4 reinforce our “belief” that the elephant will come back in a week’s
time: the area under the curve for the Prior 4 shows more than a 50% chance of
returning. With increasing knowledge, the shape of the probability distribution
tends to provide a clearer and clearer message. The strength of evidence
accumulated becomes stronger and stronger.
We know today that Rivaldo came back to his home range in 1–2 days after the
attempted translocation. With this outcome our knowledge has increased a little
further, which will be described by the “Posterior”.
If we started assuming the Prior
1 (Figure 2) was the best, the experiment result (Rivaldo
coming back in less than a week) would produce a Posterior that is unexpected.
In Figure 3(a) the flat, uninformative Prior provides a tilted Posterior: this
indicates that our “beliefs” were seriously inadequate. If we started assuming
the Prior 4 (Figure 2) was the best, the same experiment result (Rivaldo coming back in less than a week) confirms the
general trend of the Prior. The Posterior (Figure 3(b)) only slightly shifts
towards 1, which confirms further that adult male elephants are attached to
their range.
To conclude, it is very important
that managers do not confuse unpredictable events with uncertain events that
both contain an element of randomness. Ignoring published scientific knowledge
in wildlife management is like playing against a person who has a biased coin:
the price for playing this game can be high, and an elephant translocation
effort is indeed costly.
Table 1. Listing published
knowledge of elephant behavior increases the
probability of predicting operational success.
Accepted hypothesis /
observations and references |
Translocation
likely to succeed? |
Translocation
likely to fail? |
Elephants have ranges (Baskaran
et al. 2018a) |
0 |
1 |
Elephants like human food (Puyravaud et al. 2016) |
0 |
1 |
Elephants are social (De Silva
& Wittemyer 2012) |
0 |
1 |
Translocation is dangerous
(Fernando et al. 2012) |
0 |
1 |
Translocation is an added cost |
0 |
1 |
Total |
0 |
5 |
For
figures & image - - click here
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