Monitoring Tigers in India

Monitoring Tigers in India
Forest Departments
Tigers Being Top Predators
serve as a Umbrella species
for Biodiversity Conservation
– The Philosophy of Project
Tiger
Panthera tigris,
Asian biodiversity
Ecosystem services
Monitoring Tigers is like
Keeping the Pulse of the
Ecosystem
Where are the Tigers ?
97% Decline in Range Occupancy
Genetic Data suggests that over 50,000 tigers lived in the Indian
Sub-continent
Status of Tigers in Range Countries…
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Bhutan
Bangladesh
Cambodia
China
Myanmar
Malaysia
Indonesia
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:
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Vietnam
Lao PDR
India
Nepal
Thailand
Russia
:
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:
:
:
115-150 (1998, including juveniles)
500 (Forest Deptt. Estimates, 2009-10)
200 (Forest Deptt. Estimates, 1994)
No Estimate of wild Tigers Available
100-125 (Consensus Estimate)
400-500 (rough estimate)
400 Sumatran Tigers in 7 Reserves
– 100 in Unprotected Areas
150 approx.
NA
1165-1657 (in 2006-2007), 1520-1909 in 2010
155(adult tigers 2010)
200 approx (2010)
About 400 (based on track counts & Telemetry)
Between 2500 to 3500 wild tigers survive in the World
Tiger counts in India
• In the beginning of the 19th
Century: around 40,000:
guesstimate
• During 50s: 30,000 guesstimate
• 1972-73: about 2000- pugmark
method which continued till 2002.
Monitoring & Status Assessment
First Step to managing a resource is to“Take Stock of What
we Have and Where”
Tiger Task Force (2005)
First Assessment 2005-06
1411 (1165-1657) tigers
Sundarbans, Parts of NE, South & Western Maharashtra,
Indrawati and Jharkhand were not assessed
Second Assessment 2009-10
Requirement for Scientific Monitoring
and Conservation
Occupancy (Time & Space)
Population Extent & Size
Change Detection (Accuracy & Precision)
Co-variables responsible for status and change
Tiger population estimation
methodology
• The process involves double sampling in a
statistical framework having power to
extrapolate
• Involves rigorous statistical analyses
• Far more accurate than the total count by
pugmarks method
• Conducted in three phases: ground
survey, analysis of satellite data & camera
trapping
Methodology-contd.
• Phase-I: Ground survey data is collected
at beat level on signs of tigers, copredators, prey and habitat status on
transact lines by field personnel in a
standardized protocol- indirect survey
• Phase-II: Statistical and satellite data are
analysed
• Phase-III: Camera trapping is conducted
by Research Biologists, individual tigers
identified due to their unique stripe pattern
Methodology-contd.
• The methodology used for country level
assessment of tigers, co-predators, prey and
status of habitat across 17 tiger range States
covering around 82,800 sq km area
• Scientifically robust method, peer reviewed and
published in the international journal
• What we achieved?
Scientific methodology and transparency
resulted in credibility, effective strategy for
future tiger conservation & better planning
Double Sampling Approach
Generate economical and easy to collect index data from all
sampling units, e.g. tiger signs, prey encounters, human
footprint index, landscape characteristics from remotely
sensed data, etc. (Phase I – Forest Department & Phase II)
Camera Trap Mark
Indices across entire Re-capture, Distance
tiger landscapes
Sampling
Phase III – Wildlife
Biologists
Bandhavgarh
Satpura
Kanha
Pench
Double sampling
Simultaneously sample a subset of
Phase-I units to estimate absolute
abundance by statistically robust
methods, e.g. mark-recapture and
distance sampling. (Phase III)
Phase III: Camera Trap – Mark-Recapture Population Estimation
Sighting-Re-Sighting Statistical Models
Over 81,400 camera trap nights, with 37,000
man day effort by trained wildlife biologists,
covering 11,192 km2
635 individual tigers photocaptured from 29 Sites
Calibrating Tiger Signs with Tiger Density
14
Tiger Density
12
10
8
Medium
6
High
4
Low
2
Indices (Phase I & II)
against Camera Trap
Tiger Density (Phase III)
0
0
0.2
0.4
0.6
0.8
1
Tiger Sign Index (Weighted Signs/km walk)
12
Tiger Density
10
8
6
4
2
0
Low
Medium
High
1.2
Tiger Occupancy & Density Depend on
Large Ungulate Prey
Ungulate Prey
5.0
2.7
0.3
-2.0
1
2
3
Tiger Density
Categories
4
Distance to Night Lights
1.5
0.5
-0.5
-1.5
1
2
4
5
5.0
Seen
LivestockLivestock
Encountered
Anthropogenic Disturbance are
Detrimental to Tiger Occupancy &
Density
Box Plot
3.0
1.0
-1.0
1
2
3
4
D CCategories
t
Tiger Density
Tiger Occupancy recorded in 1646 km2
of Sundarban Tiger Reserve
Tagged 5 Tigers with IRIDIUM Satellite
collars
Set up 13 camera stations with bait and
near fresh water
Tiger Sign Intensity
Population & Density Estimation
Population estimated by closed population mark-recapture
in Program CAPTURE using model Mh – 11 (se 3) Tigers.
Effective Trapping Area estimated by:
Home Range Radius = 438 km2
After Habitat Mask = 257 km2
Tiger Density at 4.3 (se 0.4) and population estimated at 70
(64 to 90) tigers.
More data on collared tigers and replicate camera trap
sessions will improve estimates.
Monitoring Source Populations
2006
2010
Assessing Source Sites
2006
50
45
40
35
30
25
20
15
10
5
0
2010
Salient Points
Positive results: Increase in tiger numbers (mostly in TRs and PAs)
due to good management and protection
Matter of concern: Decline in tiger occupancy from peripheral
forest corridors connecting important populations
Major threat: Commercial poaching can eliminate isolated tiger
populations even when good habitat and prey are available (eg.
Sariska & Panna)
Thank you !