243
trap surveys is nevertheless advocated in order to better determine their interactions
and the distribution of their prey. The camera traps also provide a basis for better
estimating the abundance and density of large cats and to therefore monitor changes
and trends in populations and their behaviour.
When used in combination with camera trapping and other monitoring techniques, earth observation data can play a role in understanding how large carnivores
utilize the IBMTCL during different times of the year. These data can also be used
to address connectivity issues within and between landscapes. Several new initiatives have included the development of software (e.g., MIST, SMART, M-STrIPES)
that facilitate spatial monitoring of tiger populations including through the integration of field observations. Within such systems, there is considerable opportunity to
make better use of the large, extensive and publically available archives of satellite
sensor data.
Final Conclusions
In 1998, the global tiger population was estimated at 5000–7000 individuals
(Seidensticker and McDougal 1993). By 2014, however, the global tiger population
was at an historic low of approximately 3500 individuals, having declined by more
than 50% of what they were just a few decades earlier (Goodrich et al. 2015). Given
this situation, there is an urgent need to prioritize efforts to protect the remaining
tiger populations (Stokes 2010; Walston et al. 2010). For the most part, these are
found in PAs (Chapron et al. 2008; Rabinowitz 2009; Clements et al. 2010; Walston
et al. 2010) but there are considerable opportunities to expand their range, including
by connecting areas where they occur. This study has highlighted the potential of
using earth observation data in conjunction with ground-based (including camera
trap) surveys for better understanding the distribution, movement and preferences of
tigers and a recommendation is to develop what is termed a Tiger Observation
System (TOS) to maximize these opportunities. Whereas past use of earth observation data has been limited by availability and cost, the release of the Landsat sensor
archive and the provision of freely available Sentinel-1 and -2 radar and optical
sensor data respectively gives tiger conservation efforts additional impetus to
achieve their long term conservation and expansion of populations.
Acknowledgements The authors would like to thank the Honourable Deputy Minister, Bodoland
Territorial Areas District Shri Kampa Borgayari and his officials, Shri G.C.Basumatary, Shri
A.Swargowari, Assam Forest Department for giving the requisite permissions to carry out the
study. Dr. Jimmy Borah and his team from WWF, Dr. Bibhuti Lahkar from Aaranyak, and the Park
Authorities of India and Bhutan are thanked for providing the field data. Dr. P.S. Roy, Dr. SPS
Kushwaha and Dr. Arijit Roy from Indian Institute of Remote Sensing are also thanked for
their technical help and support.
Coupling Field Sampling with Earth Observation Increases Understanding of Tiger…
trap surveys is nevertheless advocated in order to better determine their interactions
and the distribution of their prey. The camera traps also provide a basis for better
estimating the abundance and density of large cats and to therefore monitor changes
and trends in populations and their behaviour.
When used in combination with camera trapping and other monitoring techniques, earth observation data can play a role in understanding how large carnivores
utilize the IBMTCL during different times of the year. These data can also be used
to address connectivity issues within and between landscapes. Several new initiatives have included the development of software (e.g., MIST, SMART, M-STrIPES)
that facilitate spatial monitoring of tiger populations including through the integration of field observations. Within such systems, there is considerable opportunity to
make better use of the large, extensive and publically available archives of satellite
sensor data.
Final Conclusions
In 1998, the global tiger population was estimated at 5000–7000 individuals
(Seidensticker and McDougal 1993). By 2014, however, the global tiger population
was at an historic low of approximately 3500 individuals, having declined by more
than 50% of what they were just a few decades earlier (Goodrich et al. 2015). Given
this situation, there is an urgent need to prioritize efforts to protect the remaining
tiger populations (Stokes 2010; Walston et al. 2010). For the most part, these are
found in PAs (Chapron et al. 2008; Rabinowitz 2009; Clements et al. 2010; Walston
et al. 2010) but there are considerable opportunities to expand their range, including
by connecting areas where they occur. This study has highlighted the potential of
using earth observation data in conjunction with ground-based (including camera
trap) surveys for better understanding the distribution, movement and preferences of
tigers and a recommendation is to develop what is termed a Tiger Observation
System (TOS) to maximize these opportunities. Whereas past use of earth observation data has been limited by availability and cost, the release of the Landsat sensor
archive and the provision of freely available Sentinel-1 and -2 radar and optical
sensor data respectively gives tiger conservation efforts additional impetus to
achieve their long term conservation and expansion of populations.
Acknowledgements The authors would like to thank the Honourable Deputy Minister, Bodoland
Territorial Areas District Shri Kampa Borgayari and his officials, Shri G.C.Basumatary, Shri
A.Swargowari, Assam Forest Department for giving the requisite permissions to carry out the
study. Dr. Jimmy Borah and his team from WWF, Dr. Bibhuti Lahkar from Aaranyak, and the Park
Authorities of India and Bhutan are thanked for providing the field data. Dr. P.S. Roy, Dr. SPS
Kushwaha and Dr. Arijit Roy from Indian Institute of Remote Sensing are also thanked for
their technical help and support.
Coupling Field Sampling with Earth Observation Increases Understanding of Tiger…