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Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 1
LAST ABODES OF RELIC SPECIES IN UTTARA KANNADA-SACRED GROVES
AND THEIR SILENT EXTINCTION
G.R. Rao, G. Krishnakumar, M.D. Subash Chandran, T.V. Ramachandra
Energy and Wetlands Research Group, Centre for Ecological Sciences,
Indian Institute of Science (IISc), Bangalore-12
Abstract: Uttara Kannada once known for huge track of evergreen to semievergreen forests has been
mercilessly exploited since age of British raj and is still carried over until now. What we have been
left with is highly fragmented secondary forests in coastal and easily accessible lowland areas,
encountering some good forest patches only in hilly inaccessible areas. In midst of these human
modified landscapes are the rare paradises (Sacred groves or Kans) hosting even rarer endemic and
endangered species called ‘Relic’ species more or less absent outside these Kans. As seen from the
Important value Index (IVI), endangered, emergent trees such as Dipterocarpus indicus growing to
height of 40 m or more dominated many transects such as Karikan (117.61), Kathlekan (40.82),
Ambepal (21.70), and Attigodu (18.06). Many other relic species dominating the Kan or relic forests
include poeciloneuron indicum in Karni (71.96) and Yadanal (27.47), Vateria indica in Nilvase
(68.26), Syzygium travancoricum (33.51) in Kathlekan, and Myristica fatua in Kathlekan swamp
(15.18). Evergreen percentage was highest for relic localities with 90 and above while the non relic
forests had lower evergreen percentage. Endemic percentage was highest for all the relic transects
with highest being for Karikan sacred grove (75.53). Though many of the Non-relic transects such as
Talekere showed higher endemism than other relic-transects, these endemic species were mostly
commoner endemics such as Hopea ponga, Knema attenuate which were found throughout the
Western Ghats. Non-relic forests were less in all aspects of diversity, evergreenness and endemism
compared to Relic forests. Relic forests had a total of 47 endemic species compared to only 26
species in Non-relic transects. But the real factor of importance for sacred forests emerge in the
number of critically endangered, and rarer endemics (termed as ‘Relic species’) it harbor, and are the
last abodes of habitats for these species.
Introduction
The Western Ghats of the Indian peninsula constitute one of the 34 global biodiversity hotspots along
with Sri Lanka, on account of its exceptional levels of plant endemism and by serious levels of habitat
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 2
loss (Conservation International 2005)12,4,6. These chain of hills running for about 1600 km along
with the west coast (lat.80 and 210 N and long. 730 and 780 E) covers a total geographical area of
160,000 km2. These hills which harbor extensive tropical forests, also figures on the tropical
deforestation map of India. In midst of these highly fragmented forests and other man made
landscapes, sacred groves present an interesting example of forest conservation in the Western Ghats.
Hughes and Subhash Chandran (1998)5 define ‘sacred groves’ as segments of landscape containing
trees and other forms of life and geographical features, that are delimited and protected by human
societies believing that preserving such a patch of vegetation in a relatively undisturbed state is
necessary for expressing one’s relation to the divine or to nature. So these remain as isolated patches
of forests in the midst of agricultural landscapes. Sacred places have long and diverse histories in
human cultures and demonstrate ancient links between peoples and their environments. They are a
universal phenomenon not associated with any specific religion or world view, but they have a strong
religious context and are influenced by traditional local beliefs1. These groves harbor rich biodiversity
and play a significant role in the conservation of biodiversity. The biological resources make indirect
contributions to the welfare and stability of the local environment. Their plant wealth and
conservation potential were impressive enough to acknowledge them as ‘mini biosphere reserves’3.
However, the surveys are largely limited to enumeration of plants only, neglecting analytical studies
essential for understanding the present status of vegetation needed for evolving suitable strategies for
their conservation.
Objectives
To study the
• Floristic composition in sacred groves and other protected forests.
• Qualitative and Quantitative studies of tree vegetation structure in different Kan of Relic
forests compared to their surrounding forests.
• Threats on sacred groves and their conservation strategies.
Study area
A total of 10 Kan or Relic transects were selected and another 10 from surrounding forests (Non-
Relic(Kan)) were selected from Uttara Kannada district of Karnataka State and part of Shimoga
district (table 1 and 2). Uttara Kannada district lies between 740 9’ to 750 10’ east longitude and 130
55’ to 150 31’ north latitude and extends over an area of 10,327 sq km. It is one of the two coastal
districts of the state and stretches itself along the coastline of the Arabian sea. It extends to about 328
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 3
km north-south and about 160 km east-west. It is the richest forest districts of Karnataka, endowed
with a bountiful variety of fauna and flora.
Uttara Kannada and Shimoga district harbors following important type of forests.
1. Evergreen forests
2. Semievergreen forests
3. Moist deciduous forests
4. Dry deciduous forests
5. Scrub-Savannah and thorny forests
The evergreen forests are found in places where the rainfall is more than 225 cm and form a narrow
strip along the Western Ghats. These forests harbor more soft wooded trees. The soil types of these
evergreen forests are mostly lateritic, but along the river basin it is alluvial. The moist deciduous
forests are situated in the rainfall areas of 100 cm and more. These forests are rich in timber trees. In
areas where the rainfall is below 90 cm, the dry deciduous forests are found. The scrub and thorny
forests are found in places where the rainfall is below 60 cm.
Sl Relic or Sacred forests District 1 Ambepal-2 Uttara Kannada 2 Attigodu-2 Shimoga
3 Hessige-2 Shimoga 4 Karikan-lower slope Uttara Kannada 5 Karini Shimoga 6 Kathalekan-G8-swp with S.trav Uttara Kannada 7 Kathalekan-obove settlement Uttara Kannada 8 Niluvase Shimoga 9 Hadgeri-1 Uttara Kannada 10 Yadanal Shimoga
Table 1: Relic study localities
Study localities for Non-relic or Surrounding forests
Sl Surrounding forests District 1 Atvadi Shimoga 2 Belamakki Shimoga 3 Chikmathur Shimoga
4 Gundbala Uttara Kannada 5 Halki-2 Shimoga 6 Hongodu Shimoga 7 Joginmath-1-sidapur Uttara Kannada
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 4
8 Kagarasu-mugimane Shimoga 9 Salkodu-5 Shimoga
10 Talekere-Sidapur Uttara Kannada
Table 2: Non-Relic study localities
Materials and Method
For this study, transect with a total length of 180 m with 5 quadrats each consisting of alternate 20 x
20 m quadrats was used. In each quadrat all the trees at or above 10 cms DBH (>30 cms GBH) were
enumerated at 1.3 m height, identified, or samples collected (whenever possible) if field identification
was not possible and were pressed for herbaria for future identification. Other features like epiphytes,
climbers, parasites, any disturbances like lopping, logging etc., were also noted. Canopy cover was
noted and ground litter quantity was weighed. General information such as ground control points
using a Global Positioning System (GPS), name of the locality, range, human activities such as
lopping, logging, NTFP, fuel and litter collections, fire incidence, grazing etc. were noted down.
Results and Discussion
Floristic composition
A total of 108 tree species from 32 families were noted from relic transects and 101 species from 42
families were noted from Non-relic forests. Families with highest species number in relic forests were
Lauraceae with 10 species followed by Euphorbiaceae, and Ebenaceae, with 9 species each (figure 1
and 2).
Relic transects family species no.
2
3
3
3
34
45
6
66
77
99
10
Celastraceae
Annonaceae
Dipterocarpaceae
Flacourtiaceae
Sterculiaceae
Meliaceae
Sapotaceae
Myristicaceae
Clusiaceae
Moraceae
Rubiaceae
Anacardiaceae
Myrtaceae
Ebenaceae
Euphorbiaceae
Lauraceae
Figure 1: Family species richness in Relic transects
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 5
Non-relic transects family species no.
2
2
3
3
3
3
4
4
4
4
5
6
6
7
8
Apocynaceae
Bignoniaceae
Combretaceae
Meliaceae
Sapotaceae
Sterculiaceae
Clusiaceae
Flacourtiaceae
Myristicaceae
Rubiaceae
Moraceae
Ebenaceae
Lauraceae
Anacardiaceae
Euphorbiaceae
Figure 2: Family species richness in Non-Relic transects
Non-relic transects had family Euphorbiaceae with highest of 8 species followed by Anacardiaceae
(7) and Lauraceae and Ebenaceae with 6 species each. Families such as Dipterocarpaceae which are
sure indicators of primary forests were not present in Non-Kan transects due to the secondary nature
of the forests. Other important primary forest representing families such as Myristicaceae, and
Lauraceae showed very less species and individual diversity. Euphorbiaceae family with more of
deciduous undergrowth species were more represented in Non-Kan transects.
Species diversity
Only 3 localities Karini, Nilvase and Yadanal from relic transect had significantly more species
compared to other surrounding forest (figure 3). Others did not show much significance as deciduous
species contributed for the somewhat higher species diversity in Non-Kan forests.
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 6
0
5
10
15
20
25
30
35
40
45
Sp
ecie
s n
o.
1 2 3 4 5 6 7 8 9 10
Transects
Species diversityTot.spp (Relic)
Tot.spp (Non-Relic)
Figure 3: Species diversity in different Relic and Non relic transects
Forest canopy height
Canopy height was more in the relic forests compared to that of their surrounding forests. More
prominent were Diptero dominated forests such as Hadgeri (21.90) and Ambephal (19.62) etc., due to
large emergents like Dipterocarpus indicus and Syzygium gardnerii (figure 4). In Non-relic forests
such as Talekere the average height was as low as 10.6 indicating the secondary nature of the forest.
Canopy height
0
5
10
15
20
25
1 2 3 4 5 6 7 8 9 10
Transects
He
igh
t
Aver.height(m) (Relic)
Aver.height(m) (Non-Relic)
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 7
Figure 4: Canopy height in different Relic and Non-relic transects
Tree species dominance based on Important value index (IVI)
As seen from the IVI, Dipterocarpus indicus an endangered, emergent trees growing to height of 40
m or more dominated many transects such as Karikan (117.61), Kathlekan (40.82), Ambepal (21.70),
and Attigodu (18.06). Other notable relic endemics dominating the Kan or Relic transects include
Poeciloneuron indicum in Karni (71.96) and Yadanal (27.47), Vateria indica in Nilvase (68.26),
Syzygium travancoricum (33.51) in Kathlekan, and Myristica fatua in Kathlekan-swp (15.18).
Other important trees with high IVI were Canarium strictum, Aglaia anamalayana, Hopea ponga,
Garcinia talbotii, Syzygium gardeneri, Knema attenuata, Pallaquium ellipticum, Myristica
dactyloides etc.
Non-relic transects had Olea dioca with higher IVI occurring in 6 out of 10 transects indicating the
secondary nature of the forests. Other trees with higher IVI include Knema attenuate, Holigarna
arnottiana, Hopea ponga, and Symplocos racemosa.
Basal area
Relic-transects had the highest basal area with 85.41 recorded for Karikan with huge Diptero trees,
followed by Vateria indica for Niluvase (47.47) (figure 5). Non-relic transects like Atvadi had higher
basal areas contributed by species such as Diospyros crumenata lacking rarer endemics and
endangered species which highly contributed to the relic transects.
Per hectare basal area
10.12
23.52
25.69
29.05
29.87
31.39
31.48
46.03
47.47
76.13
27.70
35.87
38.42
41.24
41.29
48.80
48.87
53.61
53.69
85.41
1
2
3
4
5
6
7
8
9
10
Tra
ns
ec
ts
Per.hec basa.area(Non-Relic)
Per.hec basa.area(Relic)
Figure 5: Per hectare basal area in different transects
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 8
Evergreenness percentage
Evergreen percentage was highest for relic localities with 90 and above while the non relic forests had
4 transects below 90 having mixture of other deciduous species such as Terminalia sps,
Lagerstroemia microcarpa, Glochidion sps, etc., which shows the past opening up of forest canopy
(figure 6).
Evergreenness
10
20
30
40
50
60
70
80
90
100
1 2 3 4 5 6 7 8 9 10
Transects
Everg
ren
ness p
erc
en
tag
e
%Evg (Relic)
%Evg (Non Relic)
Figure 6: Evergreeness percentage in Relic and Non-Relic transects
Shannon Diversity
Highest diversity was found in relic forests with Yadanal having 3.15 shannon value. Non-relic
forests also had higher Shannon diversity which were also contributed by other deciduous species.
Only in Talekere the Shannon value was low with 1.5 due to Hopea ponga dominance (figure 7).
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 9
Figure 7: Shannon diversity in Relic and Non-relic transects
Percentage Western Ghats
Endemic percentage was highest for all the relic transects with highest being for Karikan sacred grove
(75.53) (figure 8). Though many of the Non-Relic transects such as Talekere showed higher
endemism than other relic-transects, this higher endemism was mostly contributed by widely
distributed common endemics such as Hopea ponga, Knema attenuate found throughout the Western
Ghats. On the other hand the relic transects had endemic, rare or endangered species such as
Syzygium travancoricum, Vateria indica, Dipterocarpus indica, Pallaquium ellipticum, etc.,
contributing more to the endemic percentage (table 3).
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 10
0
10
20
30
40
50
60
70
80P
erc
en
tag
e e
nd
em
ism
1 2 3 4 5 6 7 8 9 10
Transects
Percentage endemism%W Ghats (Relic)
%W Ghats (Non-Relic)
Figure 8: Percentage endemism in Relic and Non-relic transects
Locality dipind poeind palell myrfat gymcan semkat syztra vatind madbur Status Ambepal-2 + − − − − − − − − Relic attigodu-2 + − − − − − − − − Relic hadgeri-1 + − − − − − − − − Relic hessige-2 − − + − − − − − − Relic Karikan-lower slope + − − − − − − − − Relic karini − + + − − − − − − Relic Kathalekan-G4-obove settlement -slope + − + − − − − − − Relic Kathalekan-G8-swp with S.trav + − + + + + + − + Relic niluvase − − − − − − − + − Relic yadanal − + − − − − − − − Relic
atvadi − − − − − − − − − Non-Relic
belamakki − − − − − − − − − Non-Relic
chikmathur − − − − − − − − − Non-Relic
gundabala − − − − − − − − − Non-Relic
halki-2 − − − − − − − − − Non-Relic
hongodu − − − − − − − − − Non-
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 11
Relic
joginmath-1-sidapur − − − − − − − − − Non-Relic
Kagarasu-mugimane − − − − − − − − − Non-Relic
salkodu-5 − − − − − − − − − Non-Relic
Talekere-sidapur − − − − − − − − − Non-Relic
Table 3: Relic species present in different Kan and Non-Kan transects.
Discussion
Non-relic forests were less in all aspects of diversity, evergreenness and endemism compared to Relic
forests. Relic forests had a total of 47 endemic species compared to only 26 species in Non-relic
transects. But the real factor of importance for sacred forests emerge in the number of critically
endangered, and rarer endemics (termed as ‘Relic species’) it harbor, and are the last abodes of
habitats for these species. Most of the secondary evergreen forests lack these relic species and have
commoner endemics found throughout the Western Ghats. Uttara Kannada is the northern most
boundaries for most of these relic species, and they hardly occur further north. Also the rainfall and
the number of dry period months restrict most of the relic species moving further north. Most of these
primary relic forests have high water shed values harboring numerous perennial springs and streams,
compared to dry stream courses in Non-Relic forests. Hence these forests are critical for water shed
management and loss of these areas would be a death blow to the perenniality of the main river itself.
Most of these relic forests are now in state of stress due to various anthropogenic factors such as
logging, land encroachment for Areca and other crop cultivation, fire, small and large developmental
projects, etc. Many sacred groves are left with only single tree species, and one would hardly be
surprised such Diptero forest existed before (figure 9).
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 12
Figure 9: Lone Dipterocarpus indicus tree surrounded by secondary forest.
All the sacred groves surveyed had high vulnerability for extinction due to encroachment and other
land use changes (figure10, 11 and 12). Many areas have been burnt and many tree saplings are
covered with weeds such as Eupatorium, and other invasive weeds and climbers (figure 13, 14).
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 13
Figure 10: A virtual paradise (sacred grove in back ground) in no forest zone.
Figure 11: Sacred site in Kan
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 14
Figure 12: Myristica fatua tree burnt for Areca cultivation.
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 15
Figure 13: Last gasp of breath for Myristica fatua entangled and covered with climbers and
weeds.
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 16
Figure 14: Swamp forests water diverted to Areca gardens leaving swamps high and dry to die
silently.
Recommendations
• To clearly recognize and demarcate the importance of relic evergreen forests from Non-relic
evergreen forests.
• Maximum priority to be given to these relic forests as these harbor endangered and rare
endemics which once lost are lost for ever.
• To prohibit any kind of human disturbance including litter collection, pole and fuel wood
collection inside the groves.
• To declare Kans such as Karikan, Kathlekan etc., as heritage sites for their complete water
shed protection and restoration.
• To encourage and appeal resident peoples inside the relic forests for relocating outside these
forests by providing suitable compensations.
Lake 2010: Wetlands, Biodiversity and Climate Change
22nd-24th December 2010 Page 17
• Even small fragments of one or two relic trees present should be declared for protection as
they may be the last remaining populations of these areas.
Acknowledgement
We would like to thank Karnataka forest department and staff, Uttara Kannada and Shimoga division,
for all their assistance in carrying out the project. Thanks to, Dr. Divakar K Mesta, Mr. Sameer Ali,
Dr. Rajashree Ray, Mr. Vishnu D Mukri and Mr. Srikanth Naik for making this field work a
successful and memorable event. Finally we thank all those forest dwellers, and other peoples directly
or indirectly assisted in carrying out this project.
References
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Ramachandra. 2008. Discovery of Two Critically Endangered Tree Species and Issues
Related to Relic Forests of the Western Ghats.
3. Gadgil, M., & Vartak, V. D.1981. Studies on sacred groves along the Western Ghats from
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