The current rate of habitat loss today is the highest witnessed in modern history. A direct impact is the large-scale extinction of species. Recent studies have indicated the current global extinction rate exceeds more than 400 species a day.This staggering loss of biodiversity has prompted a global call for species conservation in and around threatened habitats.
The challenges of modern conservation programs result from working with very small and declining populations, where many animal communities can be fewer than 50 individuals. These small and vulnerable populations can be severely impacted by conventional taxonomic actions such as specimen collection.
In recent years there has been a resurgence of interest in the herpetofauna of Sri Lanka.
The amphibian identification keys which are currently accepted
and in use today by researches, are based on specimen capture and
handling. Amphibian research using conventional non-destructive
sampling methodology includes activities such as stomach
pumping and toe clipping. But the simple act of catching and
holding a specimen can lead to the transmission of fungal diseases
and has been recorded to cause lesions and breakages.
In response, RRI, funded by the National Geographic Society, ran a year long amphibian research project to research and develop non-destructive amphibian sampling techniques.
Non-destructive sampling techniques
Other than visual observation and photographing a specimen the most obvious field character is the call. All Sri Lankan amphibians, except the worm-like sub-fossorial Gymnophonids, engage in vocalization. Each species has a very particular breeding call, a feature that is a character in modern taxonomic processes today. The call helps us to immediately identify the animal.
However, range of calls and the problem of attenuation, or the call becoming indistinct as a consequence of background noise; often makes identification based only on the call difficult.
The studies conducted by RRI in a National Geographic funded research project on amphibians suggested that many species were extremely specific in their choice of habitat.
This was especially true during breeding. Recorded observations over one year resulted in the construction of a micro-habitat map and related temporal categorization. This map identifies the times of day or night when a species would normally call and the microhabitat the species would occupy when calling.
The results of the project have been collated and turned into a booklet entitled "A Field Key for the Identification of Amphibians at Hiniduma" which you can download below.
» Download "A Field Key for the Identification of Amphibians
at Hiniduma" (PDF, 6.3MB)
In addition, you can listen to some of the amphibian calls recorded during the project, by clicking on the links below:
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