Conservational significance of Dunumadalawa Forest Reserve in Central Sri Lanka based on the endemism of its avifauna

Abstract

Abstract:The concept of endemism is useful in evaluating the biological significance and uniqueness of an area. It is a meaningful alternative to simple species richness and can be used as a relevant measure in assessing conservational significance. Dunumadalawa (7 o 17'00"N; 80 o 38'49"E; 548-972 m above sea level) is a semi-isolated, hill country wetzone forest reserve located in Kandy District, Sri Lanka. It is approximately 480 ha in extent, and comprises mainly of secondary growth forest. The objective of the present study was to determine the level of endemism of its avifauna to justify its conservational significance. The study was carried out from January to September, 2015. A line transect integrated with a point count method was used to collect data. Peak sampling hours were between 0600-0900 h and 1500-1800 h in sites selected by systematic random sampling. Density estimation was done using Distance® software. As a control, results were compared with those of nearby home gardens. According to Shannon (H') and Simpson (1-D)Diversity Indices avifaunal diversity in Dunumadalawa was comparatively higher (H = 3.56,(1-D) = 0.959) than that of the home gardens (H = 2.98, (1-D) = 0.923). Dunumadalawa harbours 13 out of 33 endemic bird species in Sri Lanka (39.4 %) and 29 endemic subspecies out of 68 (42.7 %). The forest is also refuge for 10 of the 23 (43.5 %) restricted range bird species. Due to the presence of endemics and restricted range species, Dunumadalawa, which serves as a habitat island in the midst of a large urban area, merits special conservation attention.

Diversity and distribution of avifauna at Warathenna-Hakkinda Environmental Protection Area in Kandy, Sri Lanka

“…The 74 species of birds recorded from the EPA represents about 16% of the island's total bird species. This indicate that the species richness in this EPA is higher than those reported in many other areas around Kandy city limits (Karunaratna 1986;Wijesundara & Santiapillai 2001;Ellepola 2014;Weerakoon 2015;Hettiarachchi & Wijesundara 2017). However, the bird species richness in Warathenna-Hakkinda EPA is lower than what is recorded in the Gannoruwa Forest Reserve (84 species) which is located adjacent to the EPA with an extent of 2.1 km 2 (Rathnayake et al 2016).…”

“…In addition, it represents 26% of endemic bird species of the island (MOE 2012;Gabadage et al 2015), while only 11 endemic species have been recorded from the Gannoruwa forest (Rathnayake et al 2016). The number of endemic species is a measure that can predict the amount of human influence (Linder 1995;BirdLife International 2008;Hettiarachchi & Wijesundara 2017). Typically, undisturbed natural forests in the wet zone harbor many endemic species.…”

“…This is possibly because there is very little distinction between these two habitats in terms of floristic characteristics. Several studies have shown that the bird distribution and diversities highly depend on the heterogeneity of the habitats (Bambaradeniya et al 2003;Wijesundara & Silva 2005;Karunarathna et al 2011;Subasinghe & Sumanapala 2014;Weerakoon 2015;Rathnayake et al 2016;Hettiarachchi & Wijesundara 2017;Chandrasiri et al 2018). The higher bird diversity in the riverine forests in the EPA may be attributed to the availability of relatively more distinct habitats.…”

Assessing and understanding diversity and foraging guilds of bird community structure in Gautam Buddha Wildlife Sanctuary, Bihar and Jharkhand, India

“…The habitat heterogeneity hypothesis suggests that a landscape's species diversity increases with the number of habitats because of an expansion in the number of partitionable niche dimensions (Cramer & Willing 2005;Chakdar et al 2016). Numerous studies have revealed that the distribution and diversities of bird species were highly dependent on habitat heterogeneity (Hettiarachchi & Wijesundara 2017;Chandrasiri et al 2018;Panda et al 2021;Thilakarathne et al 2021).…”