Or why we shouldn’t take those large odd-looking animals for granted.
Step into any nursery or play room, take a quick walk down the isles of your local bookstore or library. Or just look at the clothing and toys we surround children with. They are full of images of iconic animals – giraffes, rhinoceros, hippos, lions, elephants…
We use these animals to teach the alphabet, and cherish them as beloved characters in our story books. They adorn everything from birthday cards to blankets.
What would the world be like without them? Continue reading
The Uda Walawe Elephant Research Project is now approaching eight years, a unique study of Asian elephants. Because elephants are such long-lived animals, it takes a long time to understand them – particularly for important variables like who reproduces and how often. Studies of wild African elephants have been conducted at multiple sites over 10 years or more (in some cases as many as 40!), but this has not been the case for the Asian species in the wild. There have been long-term records of Asian elephants populations in captivity from places like Myanmar, where they have long been used in timber camps, and it’s interesting to see how the two compare.
This past December we published a comprehensive paper analyzing six years of data on the wild Asian elephants of Uda Walawe National Park, Sri Lanka. This paper is one of a kind as it has been difficult for researchers to successfully monitor wild Asian elephants due to the difficulty of their habitats, and the logistical challenges of conducting steady research over longer time periods.
Tailless was one of the venerable elders of our population. She was especially important for this study for two reasons: she was unmistakable even after dying due to her uniquely broken tail, and her skull and jaw were recoverable. The wear on her teeth showed her age to be around 60 or more, meaning female elephants in Uda Walawe can potentially live out their full lifespans. We aged other females in the population relative to Tailless.
This is a question that has been frequently put to us. Typically, Asian elephant numbers have to be estimated through indirect evidence, usually dung. This is because they are often found in dense habitats where visibility is poor and tracking is difficult. In other locations, such as dry reservoir beds, elephants may be plainly visible but only at certain times of year. But Uda Walawe is an exception. Encompassing large tracts of savannah-like grassland as well as forest and scrub, and having a fairly well-maintained road network thanks to tourism, the park allows researchers to watch elephants directly all-year round. This is what has given the project an unparalleled view of the lives of wild Asian elephants as they naturally live.
Age classes by size, based on calves of known age. The ‘newborn’ in this picture is actually several months old, but less than one year (click for larger image).
In the past five years the Uda Walawe Elephant Research Project has been dedicatedly following the moves of practically every elephant ever to visit the national park. It is an ongoing collaboration between Dr. Devaka Weerakoon at the University of Colombo, and Dr. Shermin de Silva, formerly at the University of Pennsylvania and now full-time director of the research program. By painstakingly photographing and identifying each and every adult, the study keeps track of who was seen, where, and when. This has given us a detailed picture of not only how many elephants there are, but approximately how many individuals there are of different ages, and at which times of year they are present.