• Introduction
• Study Area
• Materials and Methods
• Results and Discussion
• Conclusion
• References
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Introduction

Tropical forests, which harbour most of the world’s plant diversity, continue to be destroyed at unprecedented rates (Myers et al., 2000; Pittman & Jorgenson 2002). The faunal species associated with these forests are also affected due to one or another reason. The wet evergreen forests of the Western Ghats of India are one of the global biodiversity hotspots, being rich in biodiversity and endemic species (Myers et al., 2000), it is also under the threat of deforestation. It harbours some of the relic elements in the remnant forests, which are in patchy distribution. Myristica swamps are one such threatened ecosystems occurring in these remnant forests of Western Ghats. They are undoubtedly priceless assets for the evolutionary biologist, since many features of Myristicaceae are primitive in origin and hence regarded as ‘living fossils’.

What are Myristica swamps?
Swamps are wetlands dominated by woody plants. They have a fairly deep settlement of water and minimal growth of emergent plants. A marsh, though sometimes used synonymously with swamp is more applicable to a large area of wetland where the dominant vegetation consists of low-lying grasses, rushes and sedges. Swamps have a high water table and occur near rivers, streams, and lakes. 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. Freshwater swamps occur in many parts of the world, namely, Valleys of Mississippi and its tributaries, in Sweden, Odzala National Park, Congo, in the Malaysian region, Papua New Guinea, Swamp forests fringe the Amazon and its tributaries, etc. In India, freshwater swamps are reported from the Siwalik and Doon Valley and the Brahmaputra Valley (Rao, 1994).

Myristica swamp is any freshwater swamp where any one or both of the exclusive swamp growing trees of the family Myristicaceae namely Gymnacranthera canaria or Myristica fatua var. magnifica are present. These swamp species may occur in association with some other, usually evergreen trees having varied degrees of flood tolerance.

Distribution of Myristica swamps
Davis et al. (1934), in their working plan for North Mangalore Forest Division Madras reported about “swampy evergreens” with Myristica spp. confined to low lying poorly drained areas, without specifying the exact locations. However, KrIishnamoorthy (1960) reported Myristica swamps, for the first time, as a special type of habitat from Travancore. These swamps were found in the valleys of Shendurney, Kulathupuzha and Anchal forest ranges in the southern Western Ghats. Champion and Seth (1968) classified such swamps under a newly introduced category ‘Myristica Swamp Forests' under the Sub Group 4C. Talbot (1911), in The Forest Flora of the Bombay Presidency and Sind vol. II, reported just one locality, near Malemane, in Siddapur of Uttara Kannda for Myristica magnifica. The northernmost swamp that is known is associated with a sacred grove in the Satari taluk of Goa (Santhakumaran et al. 1995). However, they have not reported M. fatua or G. canarica from the Goa locality. The photographs in their paper, however, are indicative of the presence of G. canarica, thereby meriting the classification of the habitat as a Myristica swamp.

Varghese and Kumar (1997) differentiate between two types of swamps having Myristicaceae, in the Travancore region: 1. Myristica swamp forest, restricted to below 300 m, fringing sluggish streams. 2. Tropical sub-montane hill valley swamp forest- found as narrow strips of water-logged areas. Whereas, the former has M. fatua as well as G. canarica, in the latter, G. canarica is found along with Mastixia arborea and several others. Such bifurcation of these swamps does not have enough justification. The Atlas of Endemics of the Western Ghats (India) by Ramesh and Pascal (1997) shows that G. canarica and M. fatua occur from sea level to 700 m and 1000 m altitudes respectively.

More detailed studies on the Myristica swamps of Uttara Kannada in Central Western Ghats have been made recently. These swamps are isolated and situated in localities from near sea level to about 450 m altitude (Figure 1)(Chandran et al., 1999; Chandran and Mesta, 2001).