The Role of Different Ecosystems to Maintain Odonate and Butterfly Diversity in Mattakelle Tea Estate, Sri Lanka

Abstract

A survey on dragonfly and butterfly was conducted at Mattakelle Tea Estate with the objective of assessing the significance of a given tea plantation ecosystem in maintaining dragonfly and butterfly diversity. Odonate and butterfly communities of selected different habitats (seasonal stream, home gardens, small reservoir, Eucalyptus plantation, tea field, marshy land and secondary forest) assessed using line transect method. Dragonfly and butterfly counts were made along two 100 m x 10 m line transects and 30 minutes were spent at each habitat starting from 6.30 – 7.00 am in the morning and same methodology was repeated in all habitats. Other ecological parameters such as air and water temperatures, %RH, pH and EC were also recorded. The intensity of observations was 8 days per month. During two months sampling, 13 species of Odonate and 46 species of butterflies were recorded. Interestingly, 7 dragonfly and 8 butterfly species are in the national threatened category. Present study indicated that small scale reservoir and marshy land habitats maintain the highest dragonfly diversity recording 10 and 8 species where Shannon index (H) = 2.17 and 2.01, respectively. Conversely, home garden and secondary forest habitats recorded significant butterfly diversity with 33 and 32 species where (H) = 3.31 and 3.28, respectively. This can be explain, as the home garden and secondary forest habitats are well-structured with more plant species that provide feeding and nectarine plants for butterflies. Continuous water supply and water quality may support to maintain highest dragonfly diversity in small reservoir and marshy land habitats. Water sources in home garden and secondary forest have been dried in study period therefore dragonfly diversity was relatively low. Some of the recorded odonate taxa can be used as reliable indicators of ecosystem health. Vegetation structure and the complexity of the ecosystem in tea plantations play a vital role in sustaining odonate and butterfly fauna. Several conservation measures such as increasing plant diversity, introduction of shade trees, feeding and nectarine plants and conduct of good agricultural practices are recommended to protect and conserve Odonate and butterfly diversity.

Full text

Proceedings of the International Forestry and Environment Symposium 2014 of the Department
of Forestry and Environmental Science, University of Sri Jayawardenepura, Sri Lanka. pp 133
The Role of Different Ecosystems to Maintain Odonate and Butterfly Diversity in
Mattakelle Tea Estate, Sri Lanka
J. D. Kottawa-Arachchi1,*, R. N. Gamage1 and G. G. Jayathilake2
1. Hill-Country Environment Association, Tea Research Institute, Talawakelle, Sri Lanka
2. Mattakelle Tea Estate, Talawakelle, Sri Lanka
Corresponding Author: jeevan1188@yahoo.com
Abstract
A survey on dragonfly and butterfly was conducted at Mattakelle Tea Estate with the objective
of assessing the significance of a given tea plantation ecosystem in maintaining dragonfly and
butterfly diversity. Odonate and butterfly communities of selected different habitats (seasonal
stream, home gardens, small reservoir, Eucalyptus plantation, tea field, marshy land and
secondary forest) assessed using line transect method. Dragonfly and butterfly counts were made
along two 100 m x 10 m line transects and 30 minutes were spent at each habitat starting from
6.30 – 7.00 am in the morning and same methodology was repeated in all habitats. Other
ecological parameters such as air and water temperatures, %RH, pH and EC were also recorded.
The intensity of observations was 8 days per month. During two months sampling, 13 species of
Odonate and 46 species of butterflies were recorded. Interestingly, 7 dragonfly and 8 butterfly
species are in the national threatened category. Present study indicated that small scale reservoir
and marshy land habitats maintain the highest dragonfly diversity recording 10 and 8 species
where Shannon index (H) = 2.17 and 2.01, respectively. Conversely, home garden and secondary

forest habitats recorded significant butterfly diversity with 33 and 32 species where (H) = 3.31
and 3.28, respectively. This can be explain, as the home garden and secondary forest habitats are
well-structured with more plant species that provide feeding and nectarine plants for butterflies.
Continuous water supply and water quality may support to maintain highest dragonfly diversity
in small reservoir and marshy land habitats. Water sources in home garden and secondary forest
have been dried in study period therefore dragonfly diversity was relatively low. Some of the
recorded odonate taxa can be used as reliable indicators of ecosystem health. Vegetation
structure and the complexity of the ecosystem in tea plantations play a vital role in sustaining
odonate and butterfly fauna. Several conservation measures such as increasing plant diversity,
introduction of shade trees, feeding and nectarine plants and conduct of good agricultural
practices are recommended to protect and conserve Odonate and butterfly diversity.
Key words. Biodiversity, conservation, dragonfly, butterfly, tea plantation, ecosystem