People of the region have from time immemorial depended on the forest ecosystem for most of their needs including water.  The forest harbours plants collected for spice such as Piper nigrum, Myristica dactyloides, Cinnamomum sps., etc. People regularly harvest non timber forest products (NTFP’s) such as Phyllanthus emblica, Flacourtia Montana, Artocarpus sps., Garcinia sps., Mangifera indica, Canarium strictum, etc. Large amounts of medicinal plants also exists such as Terminalia bellirica, Alpinia malaccensis, Alstonia scholaris, Anamirta cocculus, Anthocephalus cadamba, Antidesma menasu, Ardisia solanaceae, Asparagus racemosus, Bischopia javanica, Salamalia malabarica, Eleocarpus tuberculatus, Canscora sps., Embelia sps., Holarrhena antidysentrica, etc. Sedges such as Cyperus pangorie are used for making mats, leaves of palms such as Caryota urens and Arenga wightii are used for thatching houses. Trees such as Artocarpus hirsutus, Lagerstroemis microcarpa, Mangifera indica, Calophyllum sps., Terminalia sps., etc., provide the necessary timber for construction of houses and equipments. Forest leaf manure from Terminalia, Vateria indica, etc., is used for paddy cultivation.  These forests act as watershed areas collecting the rain water and letting it to the myriads of tiny streamlets which in small amounts join and form large streams and rivers, thereby assuring their perenniality. 

Floral diversity : Total of 184 plant species from 72 families were enumerated during the random opportunistic survey in the river basin. The sampling locations harboured large number of plants evident from 90 trees, 25 shrubs, 15 climbers, 50 herbs, 2 palms, and 2 ferns. Herbs also included orchids such as Flinkingeria nodosa, Dendrobium aquem, D.ovatum, Trias stoksii, etc. Many of these and Cyperus pangorie was almost common along the stream. Endemic species such as Holigarna grahmii, H.arnottiana, Myristica dactyloides, Vateria Indica, Gordonia obtuse, Canarium strictum, Artocarpus hirsutus etc., were found in most of the localities. However, huge trees of Vateria indica and their saplings were observed in most of the localities in large numbers as compared to the other species. This evergreen tree is almost rare or absent in the northern districts such as North Kanara and Shimoga but it is found growing profusely here. The other common trees observed were Mangifera indica, Mallotus Philippensis, M.tetracoccus, Polyalthia fragrans, Aglaia sp., Bischopia javanica, Cinnamomum macrocarpum, Diospyros sps., Garcinia cambogia, Ficus sps., Linoceira malabarica, Olea dioca, etc. Dipterocarpus indicus was observed in one locality.

Endemic canes such as Ochlandra scriptoria and palm Arenga wightii were common undergrowths. Another palm Caryota uren was also commonly encountered in most localities.

Riparian vegetation was also a varying characteristic with species such as lofty trees of Eleocarpus tuberculatus Carallia brachiata, Hydnocarpus laurifolia, Madhuca neriifolia, Pongamia pinnata, Vateria indica, Anthocephalus cadamba, etc.

Endemic flora : During recent years, the forest area in the district is dwindling at an alarming rate with causes directly or indirectly related to excessive extraction of forest resources and often large-scale disturbance to forest ecosystems due to developmental activities. Already extensive damage to forests and depletion of biodiversity has taken place due to some of the factors such as clearing of forest lands, urbanisation, encroachment on vast areas of forest lands for extention of arable land for tea, coffee plantations, etc., logging, mining operations, etc. The construction activities such as small and large-scale hydroelectric dams, buildings and roads also contributed extensively for the above cascade of dwindling forest area. The most hard-hit ones are the endemic plants, which are entirely dependent on a specific habitat for survival, bringing into play the “doctrine of ultimate responsibility” (McNeely et al 1990). Additionally, endemic species, by virtue of their more restricted ranges, are often among the more vulnerable components of any particular community (Balmford, A., and Long A, 1994). These restricted range species confined to highly threatened ecosystems will almost certainly hit by extinction episodes (Pimm et al., 1995) and are most in need of rapid and effective conservation action (Russel et al., 1998). In this region, of 67 endemic species, 46 species were restricted to South-West India and 10 to South-West India and Sri Lanka. The rest were endemic to India. Species wise distribution and ecological status is provided in Table 1. Hence, endemic species such as Vateria indica, Dipterocarpus indicus, Myristica dactyloides, etc., which occur in this region but are rare or absent in more northern limit should be conserved on priority with the stringent management approaches curtailing any further anthropogenic activities that is likely to disturb the forest ecosystem.

Table 1. Endemic plant species found in the study area.

Faunal diversity

Butterfly : Opportunistic sampling has been done in the six localities of the proposed project area catchment. Forty-four species of butterflies (Table 2) are found in this area belonging to five families: Family Nymphalidae is dominated by 23 species followed by Lycaenidae 8 species, Pieridae 7, Papilionidae 5 species and Hesperiidae one species. Two endangered species namely Crimson rose and Danaid eggfly are found in this region emphasising the ecological significance of the region. Many species are found mud-puddling close to the streams and some species are basking in the open canopy areas. Evening browns and Bush browns of family nymphalidae, are found in the thick litter covered areas and in the vicinity of Ochlandra scriptoria, Calamus spp. Few species like, Common Jezebel, Daniad Eggfly, Commander and Crimson rose are found foraging on Gordonia obtusa, Mangifera indica, Wendlandia thyrsoidea and Lantana camara. Lycaenidae members are found mud-puddling close to the streams.

Table 2. Checklist of Butterflies found in a region

Damsel and dragonflies : Four species of Odonates are found in this area (Table 3). The species are Clear-winged Forest glory (Vestalis gracilis), Stream ruby (Rhinocypha bisignata), Stream glory (Neurobasis chinensis) and Ground skimmer (Diplocodes trivailis). The three speices are found along the streams of Hongadahalla, Battekumri halla and Kempholé whereas, the Diplocodes trivailis is found in the forest undergrowth of Hongadahalla area. 

Table 3. Checklist of Dragon and Damselflies found in the region

Fishes : Random surveys were carried out in selected locations of these two river systems for assessing the diversity of fishes. From the three samplings, we recorded 14 freshwater fish species with 174 individuals. Table 4 details the localitywise species list and number of individuals of each species collected on a single sampling event. Of the 14 species two are endemic to the Western Ghats and two are having ‘Endangered' status as per IUCN. 

Collections of two individuals of Tor khudree, during the night sampling reveals that undoubtedly Mogerahalli river stretch and its tributaries with the combination of landscape elements like deep rocky pools, swift water current, with a canopy cover of pristine riparian vegetation is the ideal breeding grounds of this species. Sampling, distributing all over the river systems might further highlight the need for conservation of aquatic ecosystems. Table 5 provides species and its distribution based on the published literatures.

Table 4 . Localitywise species list and number of individuals collected on a single sampling effort.

‘*’ - Endemic to Western Ghats, ‘1’ – Endangered, ‘2’ – Vulnerable, and ‘3’ – lower risk.

Table 5. Checklist of freshwater fishes of Nethravathi River and Kumaradhara Rivers.

• Etroplus canarensis : This species was first described in 1877 - and never seen since, and then re-discovered in 1997. This is the third Cichlid species from Asia along with other two common species Etroplus maculatus and Etroplus suratensis.Unlike these two species, Etroplus canarensis is purely a freshwater dweller. The species is restricted only to a short river stretch of 2-3 km of the Nethravathi River. Presently, nothing much is known about the ecology, life cycle, and evolutionary aspects of this species.
• Mahseers : Several species have been reported from India and from southern India, the Tor khudree and Tor mussullah. Mahseers prefer running water with deep pools and rocky substrate. They rule the Indian waters like tiger do the jungle. Three protected sites for fishes along downstream region of Kumaradhara and Nethravathi, indicates the fish richness of the region as well as the conservation priority given to these rivers.
• Mesonemacheilus petrubanarescui : A species, belonging to Balitoridae family has been reported from Dharmasthala of Nethravathi River and so far it has not been reported from any other region.

Shishila fish sanctuary :
A stretch of about 2 km across the river Kumaradhara near Shishila of Dakshina Kannada district is one of the very few places outside of wildlife sanctuaries and National Parks, where fish enjoy any measure of protection.

Predicted impacts : Usually the species vulnerable to fragmentation are those with limited distribution, and naturally rare species with low population densities. Metapopulation dynamics suggest that even widespread population of any species is also susceptible to the effects of habitat alteration and fragmentation. Isolated local populations face higher possibility of extinction. Tor khudree is one among such species with its distribution all over southern India, but facing the threat of population decline as well as habitat shrinkage.

Amphibians
Amphibians are one of the best biological indicators of ecosystem health. In the present study, opportunistic surveys were carried out in four localities. This region being biologically rich and Table 6 enlists the previous records of amphibians from the region.

Table 6. Checklist of amphibians found in the region

As many as 23 species have been observed from the region. A critically endangered species Indirana gundia has been discovered from this region in 1986. In the present study, two endangered species Nyctibatrachus aliciae and Minervarya sahyadris were recorded, which further highlights the ecological significance of the region.  Availability of perennial sources of water has provided ample habitats for amphibians; hence they are persisting in this region even during non-monsoon periods (our sampling period).

Reptiles
A checklist of reptiles observed from the region is provided in Table 7. This list adds to the richness of the species in the region. Rat snake and Indian ornate flying snake were sighted in the Hongadahalla area.

Table 7. Checklist of Reptiles found in the region.

* Endemic to Western Ghats, ** Endemic to South India

Birds
Twenty-nine species of birds (Table 8) are found in this region. Riparian vegetation of Hongadahalla, Battekumri halla and Kempholé harbours most of the species.  Riparian and disturbed Semi-evergreen patches of Hongadahalla area harbour more species. Tree pie (Dendrocitta vagabunda), Malabar pied hornbill (Anthracoceros coronatus) and Racket-tailed Drongo (Dicrurus paradiseus) are found in the Semi-evergreen forest areas of Hongadahalla. Paradise Flycatcher (Terpsiphone paradise), Blueheaded Rock Thrush (Monticola cinclorhynchus) and Orange-headed Ground Thrush (Zoothera citrina citrine) are found in the steam vegetation of Kempholé.

Table 8. Checklist of Birds found in the region

* Endemic to Western Ghats and Srilanka.

Mammals
Mammals are listed by surveying the localities in Hongadahalla and Battekumri halla in addition to querying local people. About 19 species of Mammals are listed (Table 9) from the surveyed areas. Hanuman Langur was sighted during the fieldwork.

Table 9. Checklist of Mammals found in the region.

Note: * indicates Endemic to Western Ghats.
EN – Endangered, VU – Vulnerable, Lr-lc – Lower risk least concerned,
Lr-nt – Lower risk near threatened

Table 10 details the overall diversity, endemism and threat status of the species found in Gundia region. It is evident from both flora and fauna, that this region indeed harbours many endemic and endangered species. Nearly 36% of the plant species are endemic to Western Ghats (Figure 2), similarly among animals 87% amphibians, 41% fishes are endemic to Western Ghats (Figure 3). More importantly, the presence of four critically endangered and 14 endangered animal species in the region emphasises the unique habitats and ecological niches provided in Gundia region for these animals.  This region also falls into the high priority conservation zones of the Western Ghats (Das, et al., 2006), primarily based on the species irreplacability values (>0.8). Systematic sampling of flora and fauna covering all parts of the catchment would further substantiate higher species diversity, more endemics (both in flora and fauna), etc.

Table 10. Flora and faunal diversity in Gundia region with their ecological status.

Figure 2. Exclusive endemics Western Ghats among the endemic flora observed in Gundia region

Figure 3. Faunal diversity and endemism from Gundia catchment

Seismicity in the region
This region falls in Zone II of Seismic map and seismicity is still active with two active faults namely Kodangeri-Naravi fault (Yettinholé river) and Bhagamandala-Sulya (Kumardhara and Gundia holé) fault (Valdiya, 2001). The magnitude of earthquakes could be about M 5.5 in this region.