Faunal assemblages in Myristica swamps of Central Western Ghats,, Karnataka, India

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1 Faunal assemblages in Myristica swamps of Central Western Ghats,, Karnataka, India SAMEER ALI Energy and Wetlands Research Group Centre for Ecological Sciences Photo Karthick B

2 What are Swamps? ¾ Swamps are wetlands dominated by woody plants. They have fairly deep water and minimal growth of emergent plants. ¾ Swamps have a high water table and occur near rivers, streams, and lakes. ¾ The soils are saturated (or soaked) with water. The soil is thick, black, and nutrient-rich providing an environment for water tolerant trees and other organisms. Typical swamp dominated by Mastixia arborea and Hydnocarpus laurifolia

Freshwater swamps occur in many parts of the world. Valleys of Mississippi and its tributaries, in Sweden, Odzala National Park, Congo, in the Malaysian region, Papua New Guinea, etc.

3 Freshwater swamps occur in many parts of the world. Valleys of Mississippi and its tributaries, in Sweden, Odzala National Park, Congo, in the Malaysian region, Papua New Guinea, etc. Swamp forests fringe the Amazon and its tributaries In India, freshwater swamps are reported from the Siwalik and Doon Valley and the Brahmaputra Valley (Rao,, 1994). Green anaconda (Eunectes murinus) from the Swamps of Venezuela

4 What are Myristica Swamps? These are Freshwater swamps dominated by Myristicaceae members (Nutmeg family). Myristicaceae,, a primitive family of trees. Myristica swamps in Western Ghats Krishnamoorthy (1960) reported for the first time from the Travancore region of Southen Western Ghats. Atlas of Endemics of the Western Ghats (India), by Ramesh and Pascal (1997), provide the distribution maps of Myristica fatua and Gymnacranthera canarica, trees exclusively associated with the Myristica swamps.

6 Recent work in Uttara Kannada district of central Western Ghats (Chandran et al., 1999; Chandran and Mesta,, 2001) reported the presence of these swamps. The northernmost swamp known is associated with a sacred grove in the Satari taluk of Goa (Santhakumaran et al. 1995). The dominant tree species found in the Myristica swamps are, Gymnacranthera canarica, Semecarpus travancorica, Myristica fatua var. magnifica, Mastixia arborea etc.

Characteristic features Flooded and water logged conditions are not conducive for most plants and require special kinds of adaptations. (as in case of Mangrooves).

7 Characteristic features Flooded and water logged conditions are not conducive for most plants and require special kinds of adaptations. (as in case of Mangrooves). Simillarly swamp species also undergone ceratain modifications Root modification Aerial adventitious roots called stilt roots that spring out from the main trunk provide additional support to the swamp trees in the soft soil. Such roots might become woody and flattened with age, becoming flying buttresses' as in Myristica spp. Apart from the Myristicas,, the several flood tolerant species of the Western Ghats, such as Elaeocarpus, Holigarna, Madhuca neerifolia, Pandanus etc. also produce stilt roots. Stilt roots of Myristica fatua var. magnifica

Pond cypress in the US and Semecarpus sp., have such knee roots.

8 Some of the trees has knee roots which protrude out of the swampy soil all around the tree. At least initially the knees are spongy and apparently provide the underwater roots with air. The knees facilitate gas exchange freely (Cowles, 1975). Pond cypress in the US and Semecarpus sp., have such knee roots. Some species like, Gymnacranthera canarica has loop like roots protrude into the air from the flooded substratum in the swamp. Knee roots of Semicarpus kathalekanensis These aerial loops, which thicken with age, are studded with enlarged air pores called lenticels. Knee roots of Gymnacranthera canarica

Rhizomes Rhizomes are thick stems buried in the soils as found in many herbaceous plants such as ginger, turmeric etc. Many swamp growing ferns and herbs such as aroids have spongy rhizomes.

9 Rhizomes Rhizomes are thick stems buried in the soils as found in many herbaceous plants such as ginger, turmeric etc. Many swamp growing ferns and herbs such as aroids have spongy rhizomes. Pinanga dicksonii, a delicate, shade-loving palm endemic to the Western Ghats, and often found in the vicinity of the Myristica swamps, propagate mainly through rhizomes. Rhizomes, according to Braendle and Crafford (1987), exhibit a much greater range of flood tolerance than roots. Pinanga dicksonii Photo K V Gururaja

10 Study area The study has been carried out in the five Myristica swamps of Honnavar and Siddapur taluk, Uttara Kannada district of central Western Ghats. o o Aghanashini river % Arabian Sea Sharavathi river Halsolli Torme Mundigethaggu Malemane Kathalekan Venkatapura river 0 10 kilometers o o

11 The Uttara Kannada district, formerly North Kanara (13 52" to 15 30"N and 74 05" to 75 5"E), is located towards the centre of the Western Ghats. The district with 10,250 km² of area is one of the most forested in South India with about 70% of the land under forest cover, including forest plantations. Here the Western Ghats seldom exceeds 700m in altitude. The district is a maze of steep hills with narrow valleys. Tropical evergreen to semis emi-evergreen evergreen forests form the natural climax vegetation in most of parts of the t district, which receive 200 to 500cm of rainfall.

12 Myriatica swaps - floral diversity The swamp has high level of Western Ghat endemism among plants. A total of 64 tree species are enumerated from the five Myristica swamps. the dominant tree species are, Gymnacranthera canarica, Semecarpus kathalekanensis, Myristica fatua var. magnifica, Mastixia arborea etc. Apart from this 24 species of shrubs and herbs (which include 8 species of Pteridophytes) ) also found in the swamps.

13 The Myristica swamps are also associated with many other species which show tolerance to various degrees of flooding. However these are not swamp exclusive species. Among the trees, evergreens like Calophyllum apetalum, Dipterocarpus indicus, Elaeocarpus tuberculatus, Lophopetalum wightianum and Mastixia arborea. Recently one species also described from the Myristica swamps of Uttara Kannada Semecarpus kathalekanensis (Swaminath,, 2000). Notable of the ground layer are herbs like Alpinia malaccensis, Jerdonia indica, Neurocalyx calycinus and Schumanniatus virgatus. An aroid Lagenandra ovata and Elatostemma lineolatum and Pellionia heyneana, both members of Urticaceae,, are abundantly associated with the swamps. The Pteridophytes are Angiopteris evecta, Bolbitis appendiculata, Cyathea nilgiriensis, Osmunda regalis, Pronephrium triphyllum, Pteris, Staenochlaena palustris and Tectaria wigthii.

14 Myristica swamps - diversity faunal These swamps also harbour many endemic and endangered fauna of the Western Ghats. About six species of damselflies including Phylloneura westermanni, which is a range extension from Coorg and Wayanad (Fraser, 1933). Other species are, Clear-winged Forest glory (Vestalis( gracilis), Malabar torrent dart (Euphea( fraseri), Stream ruby (Rhinocypha( bisignata), Black-tipped forest glory (Vestalis( apicalis) ) and Pied reed tail (Protosticta( gravelyi) ) Malabar torrent dart (Euphea( fraseri)

is Papilionidae 16 species, Pieridae 13, Lycaenidae 18 and Hesperiidae 19 species.

15 109 species of butterflies representing five families are found in the Myristica swamps Family Nymphalidae dominated by 43 species. is Papilionidae 16 species, Pieridae 13, Lycaenidae 18 and Hesperiidae 19 species. Malabar tree nymph (Idea( malabarica) About 16 species of fishes. Garra gotyla stenorhynchus, Rasbora daniconius, Danio aequipinnatus are prominent species. Common Pierrot (Castalius rosimon)

About 29 species of amphibians are listed from the five Myristica swamps.

The family Dicroglossidae and Rhacophoridae comprises seven species each.

each. Some of the notable species are, Micrixalus saxicola Nyctibatrachus major, N.

16 About 29 species of amphibians are listed from the five Myristica swamps. Order Anura comprises eight families and Gymnophiona the family Ichtyophiidae. The family Dicroglossidae and Rhacophoridae comprises seven species each. Rhacophorus malabaricus Whereas the family Nyctibatrachidae and Ranidae comprises three species each. Some of the notable species are, Micrixalus saxicola Nyctibatrachus major, N. petraeus Philautus ponmudi,, P. P neelanethrus, Polypedatus pseudocruciger and Rhacophorus malabaricus. Nyctibatrachus petraeus Philautus ponmudi Photo Samer Ali, K V Gururaja

59 species of birds found in these swamps.

Calotes rouxii 22 species of reptiles which

17 59 species of birds found in these swamps. Wynaad laughing thrush (Garrulax delesserti), Great pied hornbill (Buceros( bicornis), Bluewinged parakeet (Psittacula( columboides) Calotes rouxii 22 species of reptiles which includes 13 species of snakes. Calotes sp. Cnemaspis sp.

Trinket snake (Elaphe helena helena) ) etc.

18 The notable snakes are King cobra (Ophiophagus hannah), Humpnosed pit viper (Hypnale( hypnale), Malabar pit viper (Trimersurus malabaricus), Trinket snake (Elaphe helena helena) ) etc., Humpnosed pit viper (Hypnale( hypnale) Malabar pit viper (Trimersurus( malabaricus) Photo Samer Ali & K V Gururaja

19 About 15 species of mammals found in these swamps, which include an endemic and endangered primate Lion tailed macaque (Macaca( silenus). Lion-tailed Macaque, an endangered primate of the Western Ghats,, is associated with the relics of the primary forests in Siddapur having the Myristica swamps and Dipterocapus.. Lion tailed macaque (Macaca( silenus)

20 Ecological value Swamps have Watershed value, Because the bottom of the swamp is at or below the water table, it serves to channel runoff into the groundwater r supply, helping to stabilize the water table. During periods of very heavy rains, a swamp can act as a natural flood control device (Columbia( Encyclopaedia,, 1978) Standing or slow moving water seeps continuously into the ground,, helping to replenish underground water reservoirs called acquifers (Cunningham and Saigo, 1990). The presumed widespread loss of perennial freshwater swamps such as the Myristica swamps, as evidenced by their present day rarity and fragmentation is perhaps a reminder of the progressive desiccation of the Western Ghats.

21 The swamp and its immediate surrounding forests have a number of wild fruit bearing trees. These include Garcinia, Myristica, Syzygium, Holigarna, members of Lauraceae, Meliaceae, Myrtaceae etc. which provide food for many wild mammals and birds.

22 Threats to Myristica swamps in study area In the study area most swamps are presumably extinct due to human impacts of various kinds. The swamps are encroached for agricultural lands and areca plantations. The two of the studied swamps are at risk of disapearence due to areca plantations. The pressure is mounting on the last traces of the remaining swamps, due to mainly ignorance about the value and evolutionary significance of these ancient patches of forests. Encroachment in the Kathalekan Myristica swamps Palynological studies might be of help in locating some of the past swamps.

23 Conservation The Myristica swamps in this region are in the verge of extinction due to rampant illegal conversions to agricultural lands and areca plantations. Rich biodiversity of swamps along with the evolutionarily significance icance demands the immediate policy measures to conserve these Myristica swamps fragile ecosystems in remnant forest patches of Uttara Kannada. Special efforts should be made to locate more of these swamps lying hidden in the recesses of the Western Ghats.

24 T H A N K Semicarpus kathalekanensis patch in Kathalekan swamp S Photo Samer Ali

biodiversity Joyce Jose 1,Roby T.J. 2, Ramachandran K. K. 3 and Nair P.V. 2 GIS/FIMS, Kerala Forest Research Institute Peechi, Thrissur

Myristica swamps A treasure trove of biodiversity Joyce Jose 1,Roby T.J. 2, Ramachandran K. K. 3 and Nair P.V. 2 1 Department of Zoology, Mar Thoma College, Tiruvalla. 2 GIS/FIMS, Kerala Forest Research