Supplement to
Khan 2012 - Technological enhancements needed in photo-trap approach for
forthright use by tiger population managers
L.A.K. Singh
1830-Mahatab Road, Friends’ Colony,
Old Town, Bhubaneswar, Odissa 751002, India
Email: laksinghindia@gmail.com
Date of publication (online):
26 April 2012
Date of publication (print): 26
April 2012
ISSN 0974-7907 (online) |
0974-7893 (print)
Manuscript details:
Ms # o3103
Received 16 February 2011
Citation: Singh, L.A.K. (2012). Supplement to Khan 2012 - Technological enhancements
needed in photo-trap approach for forthright use by tiger population managers. Journal
of Threatened Taxa4(4): 2551–2552.
Copyright: © L.A.K. Singh2012. Creative Commons Attribution 3.0 UnportedLicense. JoTT allows unrestricted use of this
article in any medium for non-profit purposes, reproduction and distribution by
providing adequate credit to the authors and the source of publication.
The fundamental
lesson given to budding Wildlife Managers of 1970s was that if they were sure
about the continued existence of a healthy population of predator (tiger) at
the apex of the ecological pyramid they may draw a logical conclusion that the
herbivore and the vegetative habitat forming the lower strata of the pyramid
were also in sound conditions. If
correctly implemented the status of large cats can indeed be accurately
assessed while it is not within possible reach of such order for herbivores or
the vegetation. This is true
even today.
In
the year 1972 the first All India Tiger Census was carried out by pugmark
tracking (Choudhury 1970). Thereafter census of tiger has
been carried out at intervals and based on the results and experiences of field experts at least 39 areas in India have been
identified for conservation of tiger and its habitat. Also in this process, a series of management prescriptions
have been implemented because of which tiger still survives in the wild
(MOEF-Government of India 2006). ‘Pugmark Tracking’ (Singh 1999, 2000) continued to be the accepted
method for studying large cats in India until 2004. It was also used in Bangladesh (MOEF-Bangladesh 2004) and
Sri Lanka (Kittle & Watson 2007).
There is no
disagreement that abundance of large felids is governed by the abundance of
their prey communities (eg., Karanth & Nichols 1998), but the number of tigers
determined by pugmark tracking lost trust with some as tigers were “not
sighted” in the forest. At about
this time incompletely trained persons were asked to interpret pugmark tracings
or plaster casts. Besides, the
level of implementation of pugmark tracking for large felid census varied in
different parts of India. Finally
there was one highlighted case where the actual results of the exercise were
not revealed because of administrative or some other constraint. Ultimately, the foundation provided by
all past census results from all places got discredited. It even ignored the arduous path that
was covered from 1973 to mid 1990s for expanding tiger conservation network.
In spite of
knowing well that photographing of tiger is not easy in dense forest a new wave
of interest emerged with the people and researchers for producing photographic
evidences of tigers in tiger reserves. In this context using camera-trap had the required potentiality.
Camera trap was
not new for the wildlife fraternity. I give credit to MrHoward Hunt of Atlanta Zoo who was identifying egg predators visiting nests of Alligator mississippiensis in Okefenokee Swamp National Wildlife
Refuge, Georgia, USA. Howard monitored the alligator nests during 1976 to 1985
with Kodak Instamatic X-15 cameras set with mouse-trapshutter releases and mounted on stakes. The camera was connected to the nest mound with thread. Disturbance to
the mound tripped the camera and a single photograph recorded each incident
(Hunt 1987).
During mid 1990s
demonstrations were made (Karanth 1995) and
extensively popularized for possible use of camera traps to assess populations
of tiger in India. With the
support of National Tiger Conservation Authority, from the year 2005–06 camera-trap and a series of other field exercises have
been implemented at the all-India level (Jhala et al.
2008, 2011).
The recent
publication by Khan (2012) describes one such use of camera trap in
Bangladesh. The application of
photo-trap principle with extensively improved cameras and statistical
extrapolation constitute a type of sample study. The technique is developing as an easier approach to deduce
the minimum number of tigers in inhospitable areas or areas with low tiger
density. The technique has been
successful in creating a new wave of interests for tiger conservation. It has drawn wide attention among
intelligentsia, the researchers and media as it produces photographs of tigers.
However,
considering the presently low level of field-utility for tiger managers, the
sampling method using photo traps under discussion needs to be improved. The results from the method have to
rise above the academic look and be more meaningful for forthright use by Tiger
Population Managers and the staff who are in-charge of protecting and
conserving tigers and their territories. The staff should be able to know the continued presence of tiger during
their own day to day field activities. Statistical extrapolation of sampled
‘photographic results’ is unable to ascribe this important task.
As an example,
the study (Khan 2012) involved 290 field days spanned over a period of two
years, and it could conclude, from seven photographs, the presence of five
tigers, which is 2.5% of the estimated minimum population of 200 tigers. To a small number of identified tigers
addition was made of statistically deduced virtual tigers to the extent of
97.5% of the population.
Photographing a
tiger with camera trap is laudable. But for the use of this technique to highlight the status of tiger and
help in conservation, it should be improved to obtain repetitive field
evidences of the order of 500% or more than actual existence and reject all
overlaps so that a more accurate minimum number of tigers isknown with their field details. It
should be able to discuss the figures of only non-virtual tigers, and present
details about the composition of tiger population as male, female and cub in
some kind of size-index classes representing different age classes. The result should highlight the spatial
distribution and movement areas in relation to male-female and mother-cub
dispositions with blank ranges mirroring sites of anthropogenic pressure. The usefulness of the results should
not be thwarted with possibility of changes to the population because of the
time taken in years to complete field work and deduce
results. The entire procedure
should also aim at preserving the traditional skill of forest people and
involve the field staff to such an intimate level that each staff is able to
identify himself with the tiger and its territory he is expected to protect or
conserve. The field science should
be simple and aimed for practice by field personnel who are not researchers of
any standard. For effective
conservation of a species like tiger the Manager should be equipped with
results that have not emerged because of reduced field rigors and conveniences
of sampling experiments.
It is wished that
in order to match the already-evident-utility of
pugmark tracking the photo-trap technique addresses the above mentioned
aspects. It may get identified as
the method to move with for tiger conservation in the coming decades. Science is developing fast and it could
happen sooner than we think.
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