In March 2015, documentary filmmaker Keya Vaswani sent Sanctuary Asia a series of images clicked by her friend Andrew Bembridge. To understand what was happening in Udawalawe we activated our networks and made contact with Dr. Prithiviraj Fernando of the Centre for Conservation and Research. Here, he elucidates on the specter of death that stalks the elephants of Udawalawe.
Photo: Sumith Pilapitiya.Udawalawe National Park in southern Sri Lanka is famous for its elephants. A visit guarantees close encounters with elephant herds of females and young, stately lone bulls and, on occasion, the odd male group, grazing on the abundant grass, frolicking in the water holes, jousting with each other and generally doing what elephants do. However, the winds of change have been a-blowing. The elephants are becoming harder to see and many visitors have been perturbed by the appearance of thin, haggard females and young with their ribs sticking out and their skin hanging off their bones in loose folds. In the last dry season, six starving calves were captured by the Wildlife Department and brought to the adjoining ‘Elephant Transit Home.
So what ails Udawalawe?
The history of the park is instructive. Prior to the 1950s Udawalawe was a mature tall forest with a few scattered hamlets. People eked out a living from subsistence farming based on small rain-fed reservoirs and chena (shifting cultivation). With the damming of the Udawalawe river to create a mega-reservoir in the 1960s, widespread logging and large-scale chena farming took place, destroying the forest and transforming it into grassland and savannah habitat. The 308 sq. km. park was declared in 1972, mainly to accommodate elephants displaced by the irrigation development under the Udawalawe reservoir. A number of ‘elephant drives were conducted from the developed area to the park. In the 1980s an electric fence was constructed on the southern boundary of the park to keep the elephants driven in from going back and to prevent forays by park elephants into the adjoining sugar cane fields.
By the time the park was declared, the areas cleared for chena cultivation were all colonised by Guinea grass Megathyrsus maximum, an imported fodder grass for cattle that became established and widespread in the 1800s. The typical landscape of Udawalawe consisted of large areas of Guinea grass with isolated trees. Elephants prefer grass as it is easy to gather and consume, has high nutritional value and has no toxins. Unless extensive, such as found in the African savannahs, grassland habitat by itself cannot support high elephant densities as grasses die and provide little sustenance in the dry season. In the case of Udawalawe, it is at this time of scarcity that the drawing-down of water in the reservoir with its release for cultivation, created a lush short-grassland that sustained the herds through the dry season. Fires commonly occurred in the highland Guinea grasslands in the late dry season. Mostly set by cattle herders, annually large areas of grassland went up in mighty conflagrations. However, Guinea grass is fire-resistant and the onset of monsoonal rains transformed the charred meadows overnight into lush green swards, sprouting protein-rich tender leaves that sustained the elephants through the subsequent wet season. The year-round grass availability from this two-system cycle complemented each other, making Udawalawe a high-density elephant habitat that supported over a thousand elephants through the 1990s.
Photo:Jennifer Pastorini.In the seasonal tropics, grasslands are not natural climax vegetation but a transient stage of ‘succession, the process of change from bare rock to mature forest. If one starts with sterile bare rock, with time it is weathered and microbes colonise it. These create conditions suitable for more complex organisms such as lichens. The growth and death of these create perhaps a thin layer of soil, which is then colonised by simple plants such as mosses. These in turn change conditions that make it suitable for herbs and grasses. With more time, bushes and then trees colonise the increasingly thicker layer of soil, finally creating a mature forest. This process may take hundreds or thousands of years. However this process could also become arrested at any stage. A rock on the seashore, at high altitude or in a desert may remain covered with a few lichens, due to the action of sea water, or wind, or temperature extremes. Events such as fire or flooding as well as animal or human activities may stop or reverse the process. A fire may destroy a forest and set back the clock to grassland, which then through succession becomes a forest again.
What happened in Udawalawe in the 1960s was a re-setting of the clock by humans. Extensive logging and chena cultivation destroyed the forest and created a grassland-savannah system, which was very good for elephants. Ever since, the clock of succession has been ticking and almost inexorably changing the grasslands to savannah, scrub, secondary forest and finally to mature forest. A number of factors impact grassland succession. Fire generally retards succession and maintains grasslands. It burns off the dried-up, above-ground portion of the grasses and kills seedlings of other colonising plants, but the rootstock of the grasses survive. With the next rains, the grasses sprout again whereas other scrub and tree species need to be re-seeded and start from scratch. Therefore, where annual fires occur, grasslands are likely to remain as grasslands. The ‘fire-suppression policy adopted by the Wildlife Department is a critical factor that probably encouraged succession and quickened the demise of the grasslands in Udawalawe.
Elephants and cattle have complex impacts on succession. By browsing and trampling emerging seedlings of shrubs and trees, as well as impacting the earth especially by the hooves of cattle, they retard succession. By dispersing seeds of shrubs and trees into grassland by consuming them elsewhere and depositing them in droppings in the grassland, and by overgrazing of grasses, they promote succession. Whether the overall effect is retardation or promotion of change may also depend on the density of elephants and cattle. At lower densities they may promote grasslands but at higher densities cause their decline.
Photo: Dr. Prithiviraj Fernando.The electric fencing all around the park boundary is likely another villain in the current episode. The fences on the eastern and northern park boundaries are mostly inside forest as the adjacent areas are Forest Department land. In Sri Lanka there are two conservation agencies, the Wildlife and the Forest Department. Each has its own protected area system and about 60 per cent of electric fences are between the two with elephants on both sides. Such fences within forests are difficult to maintain and within a couple of years become dysfunctional and fall down. After a time they are reconstructed. The Udawalawe fences have gone through a number of such iterations over the past three decades.
Many elephants in Udawalawe National Park also use habitats outside the protected area. When the fences are up, they are stranded either inside or outside the park and lose part of their home range. Adult males have learned to break the fences and go in and out. However the herds composed of females and young, who are also commonly driven into the park together with fence reconstruction, usually do not challenge these fences. They seem unable to adapt to sudden loss of range, lose body condition and starve to death. This happens because there is a limited number of elephants any area can support - the ‘carrying capacity. Driving elephant herds into parks and fencing them in causes the carrying capacity to be exceeded. As a result, not only the elephants that are driven in, but also the elephants that have home ranges entirely within the park suffer the consequences. Udawalawe has gone through a phase of fence reconstruction in the recent past and this may be contributory to the current situation. As Guinea grass is sensitive to overgrazing, grassland decline is hastened by the forced high density of elephants within the park created by drives and fencing. Overgrazing is further exacerbated by the daily entry of large numbers of cattle and water buffalo from the dairies bordering the park.
Another factor in grassland decline is the invasion of exotic shrubs such as Lantana and Eupetorium. In addition to their fast growth and rapid spread, few herbivores consume them. As a result, they have taken over large areas of former grassland. The effect of fire on the spread of such invasives is not clear. Possibly annual grassland fires may retard their establishment but once established, fires may promote their growth.
Photo: Andrew Bembridge.
So what can be done? Clearly if Udawalawe is to support a high density of elephants, the Guinea grasslands need to be brought back. Which is also a paradox as Guinea grass is not indigenous to Sri Lanka but a native of West Africa and is hence an invasive exotic. So should management promote something that is not ‘natural? However high elephant densities, elephant drives, electric fences, dry season grasslands in the reservoir bed, are also not ‘natural. If we want to bring back the Guinea grass for elephants, quick and appropriate management is imperative, as elephants are slow breeding, and once populations start declining they cannot recover quickly or easily. However, blind knee-jerk remedial attempts may do more harm than good. For example some areas in Udawalawe have repeatedly been cleared of scrub by cutting and removing or bulldozing, which are then colonised not by grass but by Lantana.
Photo: Jennifer Pastorini (2010).The current situation is a result of complex interactions among a number of factors. The way to figure out how the grass can be restored is by conducting trials with manipulation of the putative agents of change and monitoring. Control plots subject to combinations of different forms of vegetation clearance, fire and grazing by cattle and elephants need to be set up to assess if there is any one or combination of management actions that can restore Udawalawe to its former elephantine glory. In the short term, assessing current ranges through radio-telemetry of elephant herds and removing electric fences preventing them from using outside areas, as well as stopping cattle from entering the park would ease the dire situation and buy time. Continuing to play the fiddle while Udawalawe does not burn would hasten the day we will say:“Udawalawe National Park was once famous for its elephants."
Dr. Prithiviraj Fernando is a conservation biologist and the Chairman of the Sri Lanka based Centre for Conservation and Research. Dr. Fernando has been a member of the Asian Elephant Specialist Group for the last 15 years and is a member of the Editorial Board of the Asian Elephant Specialist Group Journal - Gajah. He is also a Research Associate of the Smithsonian Institution USA, and has received Presidential Awards for Scientific Excellence and the Whitley Award for Nature Conservation.
Photo: Prithiviraj Fernando (2015).Read More: 1. Ten Ways To Save Elephants
2. Elephants: Beyond Borders In Southern Africa
