FIGURE 1 - uploaded by Kithsiri Ranawana
Content may be subject to copyright.
Source publication
Elephants can have profound effects on the structure and composition on
woodlands. In this study, the damage caused by elephants to woody plants in the Udawalawe
National Park was investigated. The study was carried out in three major habitat types in the
Udawalawe National Park, namely grasslands, scrub forests and tall forests. Five plots were
es...
Context in source publication
Context 1
... elephant densities are associated with night temperatures are 29.4 and 23.9 C, decline in large trees (Barnes, 1985; Osborn, respectively. The park was originally forested, 2002). A 25-year study in Africa shows that however due to anthropogenic activities the elephants affected the size distribution of natural vegetation has been affected and now savanna woody component much more than the grasslands and scrubs dominate a major part of tree densities (Van de Vijver et al, 1999). The the area. Much of the forests were destroyed by extent to which elephants affect the woody chena cultivation vegetation will depend though on other factors such as tree density, age structure (Barnes, 2. Methods 1985), other herbivores (Belsky, 1984) and fire Fifteen plots, each with an extent of 250 2 (Pellew, 1983). Elephants can have profound m were demarcated randomly (five in each area; effects on the structure and composition on grasslands, scrub forests and tall forests) to cover woodlands (Barnes, 1985). Despite this impact, the total extent of the study area. Study plots relatively little is known about the factors, were selected close to park roads so as to avoid nutritional or otherwise, that in fluence food and long walks across the park which is dangerous, habitat selection in elephants (Holdo, 2003). due to the presence of large number of elephants Knowledge of these factors can help determine in the park. By using the survey tape of 100 m the role of elephant-tree interactions in shaping and nylon rope of 100 m, 50mx50m plots were forest structure and species composition, and established ( Figure 1). The coordinates of the may assist managers seeking to address plots were obtained using the Global Positioning problems associated with overexploitation of System (GPS). Subsequently all woody plants certain tree species by elephants. over 10cm diameter at breast height (dbh) and saplings which were in the study plots were MATERIALS AND METHODS enumerated. Woody plants species less than 150 1. Study Site cm dbh formed part of the lowest canopy-layer. The Udawalawe National Park is next only in All the plant species found in the experimental popularity to the Yala National Park in the plots were identified to species level. Herbarium Southern region, and acts as a refuge for a large specimens were prepared of the species that number of herbivores, especially for elephants could not be identified in the field and they where elephants can usually be observed even at were later identified comparing the to the mid-day.There are about 275-350 elephants authenticated specimens at the National living in the park currently (Department of herbarium. Wildlife Conservation, 2010). Considering the To assess the damage caused to the plants the extent of the Park which is about 32,315 ha affected plants were broadly categorized in to six 2 (323.15 km ), the elephant population density is main groups, namely, (1) Crown damage -main fairly high compared to the other areas in the branch or the canopy of the tree being pulled or country. The Udawalawe National park twisted without completely broken away from comprises of dry mixed ever green forests and the plant; (2) Bark removal -partial or complete extends to Sabaragamuwa and Uva provinces. peeling of the bark of the main tree trunk or any The park is surrounded by cultivated land and it of the branches; (3) March, 2015]Pushing down -trees and shrubs being partially damages recorded. Other than crown damage, or completelyuprooted; (5) Partially damaged -the damages caused as branch damages, bark part of the tree totally damaged; (6) Damaged removal and pushing away was fairly high in the likely to die -plants which are severely damaged grassland (Figure 2). and unable to recover from the damage.Any woody plants showing one or more of these damage types were assumed to be utilized by elephants (Ishwaran, 1983). For the final calculations, data from the 5 plots in each habitat werepooled and all the damages were calculated by using following equations.Collected data were analyzed by using Microsoft ...
Citations
... The UWNP is 308 km 2 in extent and is situated between N6°30 0 14.06 00 and E80°54 0 28.12 00 in Southern Sri Lanka (Fig. S1). The average daytime temperature of the park is 29.4°C and the annual average rainfall is 1,524 mm (Angammana, Ranawana, & Ellepola, 2015;Alahakoon et al., 2017). The rainfall is characterised by a bimodal pattern, a small peak occurring from March to April and the main rainfall occurring from October to December (Ranjeewa et al., 2018). ...
Electric fences are widely used in human–elephant conflict mitigation. However, elephants constantly challenge and overcome fences, which is a growing concern. We studied how elephants crossed the perimeter electric fence around the Udawalawe National Park (UWNP), Sri Lanka. Using camera traps, we monitored 18 fence posts and an open gate in the fence over 605 days from 2016 to 2019. Photographs of 3097 fence crossings were analysed to obtain demographic data for fence crossing elephants, crossing methods, and the daily and seasonal timing of fence crossing. We identified 77 adult males and 12 adult females that crossed the fence, which represent about 17% of the adult elephants in UWNP. Most of the crossings were through the open gate at night. Elephants used a variety of crossing methods, comprised of crossing at the open gate, at previously toppled posts, by crashing through wires and stepping over wires, as well as by using the trunk or forefeet to topple posts. Fence voltage was not a determinant of fence crossing. The frequency and timing of fence crossings varied between locations with later exits and less time spent outside, at crossing points bordering human dominated areas. Our results emphasis on the importance of taking into account the problem solving abilities of elephants in fence design and location, such as energising fence posts and constructing exclosure fences at the boundaries of crop fields and settlements, in employing electric fences to mitigate human‐elephant conflict.
... The elephant feeds on grasses which show dense growth, are easy to gather, and have few secondary compounds (Fernando, 2015). Some of the species of grasses consumed by the elephants are Panicum maximum, Cyrtococcum trigonum, Heteropogan contortus, and Cynodon dactylon (Angammana et al., 2015;Alahakoon et al., 2017). In reservoirs, as the water level drops in the dry season, parts of the reservoir bed get exposed, allowing seasonal grasses to sprout. ...
In protected areas (PAs) designated for the conservation
of biodiversity, temporal landscape changes do occur, driven by
natural and anthropogenic factors. Such changes may impact on
the conservation value of the PA. In a wildlife PA, changes in
habitat extents could adversely affect some of the faunal species.
Our objective was to assess temporal changes in the cover of three
major habitat types in the Udawalawe National Park (UWNP)
that have occurred over a short term. Based on the outcome, we
aimed to determine the potential impacts such changes would
have on the wildlife. Considering that UWNP was established
primarily for conserving the nationally threatened and flagship
species Elephas maximus, we carried out field studies and decided
on three relevant habitat types - forest, scrub, and grassland. We
used multi-temporal satellite images with ground truthing for
assessing habitat extents in the years 2005, 2010, 2015, and 2019.
Habitat cover maps were prepared using supervised classification
and changes in the extents of the selected habitats were assessed.
Between 2005 and 2019, the areas under forest and scrub had
increased. The grassland has considerably decreased, mainly
owing to invasion by scrub. Grassland depletion adversely impacts
the elephant whose preferred food is grass and the high population
of elephants in UWNP aggravates the situation. Depletion of food
resources within the park would also lead to an increase in the
human-elephant conflicts in border villages. Thus, in this study
we highlight the importance of monitoring temporal changes in
habitat cover in order to manage the PA and the inhabiting wild
elephants.
Keywords: Elephas maximus; habitat cover mapping; protected
areas; remote sensing.
... Gunawardena et al. (2015) have estimated the above ground biomass at HPNP and during the procedure several vegetation maps have been prepared using imagery from 2008-2013. There are publication related vegetation maps for some of the Department of Wildlife Conservation (DWC) managed parks; Wilpattu (Sandamali and Welikanna, 2018), Udawalawa (Angammana et al., 2015), Maduru Oya (Gabadage et al., 2015 and Muthurajawela Sanctuary (Khanh and Subasinghe, 2018). There are some previous attempts to map the vegetation of Sinharaja (Madurapperuma and Kuruppuarachchi, 2014;. ...
Availability of accurate and detailed vegetation and habitat maps is an essential requirement in the modern ecological studies. Geo-referenced vegetation maps of Sri Lanka's protected areas are scarce and only a handful of maps are available with detailed vegetation patterns. Since majority of the current ecological research work takes place within the protected area network of the island, we identified that preparing updated maps to assist the ecologists as well as the park management is highly important. In this study we developed vegetation and land cover maps for Maduru Oya and Horton Plains national parks in Sri Lanka. The procedure was based on supervised classification of Landsat 8 multispectral image data. Classification was complemented by ground truth data obtained through field surveys. The present study generated accurate (overall accuracy-92-93%; Kappa-0.89) and detailed vegetation/land cover maps and habitat types were proposed based on vegetation patterns. The results provide accurate information for ecologists and decision-makers to assist future research work as well as conservation and management of protected areas concerned.
... Asian elephants are globally threatened by rapid fragmentation and loss of habitat (Leimgruber et al. 2003). They prefer scrub forest and areas with grass, low woody plants and forest (Angammana et al. 2015). In Sri Lanka, elephants currently inhabit dry evergreen and thorn-scrub forests in the dry zone, having been largely extirpated from the wet zone rainforests by landuse changes over the last century (Fernando 2000). ...
... Details regarding food choice and seasonal diet composition of Asian elephants remain largely unknown. Relatively few studies have been carried out in Sri Lanka on the food and feeding patterns of elephants (Mueller-Dumbois 1972;McKay 1973;Ishwaran 1983;Santiapillai et al. 2003;Santiapillai & Jackson 1990;Samansiri & Weerakoon 2007;Angammana et al. 2015). ...
... Mean annual rainfall is about 1524 mm received mainly through the northeast monsoon from December to March. Mean day and night temperatures are 29.4⁰C and 23.9⁰C, respectively (Angammana et al. 2015). The Udawalawe National Park supports about 804-1160 Asian elephants, resulting in a high population density (de Silva et al. 2011) The vegetation of Udawalawe National Park is comprised of intermediate zone to dry zone transitional high forests in the northern part and interspersed areas of grass, scrub and stages of forest succession in the rest (Fig. 1). ...
Abstract. Asian elephants feed on a wide variety of vegetation but their preference for
particular plant species maybe an important factor in determining seasonal movements.
We identified 63 elephant fodder plants in Udawalawe, consisting of 19 trees and 44
herbs and grasses. Elephant fodder species mainly occurred in scrub forest (40%) and
grasslands (31%). Elephants in Udawalawe were more grazers than browsers year round.
Availability of seasonal vegetation is a possible factor, keeping elephants inside the park
during the dry season.
This study assessed the relationship between surface water distribution and elephant impacts on the Zambezi River flood plain, Mana Pools National Park woody species ecosystem. Water availability and forage are major requirements for African elephant distribution within an ecosystem landscape in Zimbabwe. Surface water unavailability reduce elephant home range to around peripheries of water bodies and this is intensifying the destruction of wood species around these water bodies. The study adopted a mixed methods research design which combined qualitative and quantitative methods. Field data were collected between 10 January 2017 and 14 February 2019. Questionnaires, interviews and field observations were the major tools used to collect data in Mana Pools National Park. Data were analysed using the Statistical Package for Social Sciences version 20.0. Inferential statistics were employed to determine the relationship between elephant activity and damage of woody species. Chi square test results revealed that there is a significant relationship (P < 0.05; P = 0.001) between elephant activity and woody species damage. This means that woody species damage in the Mana Pools National Park Zambezi Valley flood plain can be attributed to elephant activity. This study recommends that Government and Zimbabwe Parks and Wildlife Management Authourity (ZPWMA) should formulate effective elephant population analysis through periodic surveys in order to continuously update the national data base of elephant population trends in areas such as Mana Pools National Park.