Adaptive Sampling Strategy for Assessment of Avian Diversity
Abstract
Measurement of biodiversity is an important issue in ecological studies and planning
wildlife conservation. The conventional method of measurement involves sampling
in various forms such as line transects or quadrats. Many field studies appear to be
rather ad hoc in their design, especially with respect to amount of effort put in. A
crucial question in this context is how much sampling effort should be considered
enough. Earlier studies (Gore and Paranjpe 1997) indicate that for estimation of
diversity indices, a sample of 1000 individuals should suffice. On the other hand,
effort needed to estimate species richness is one order of magnitude higher. In this
paper we focus attention on estimation of avian species richness. The main issue
is distribution of efforts over time and space. ‘Time’ involves two aspects, time of
the day and season in the year. ‘Space’ involves various habitat types available in
a study site. Different sampling strategies are compared using simulation. Finally,
these are applied to species abundance data collected at some sites in The Western
Ghats. An adaptive cyclical sampling strategy appears to be useful.
Keywords and Phrases: Biodiversity, Species richness, Survey strategy, Adaptive
sampling, Simulation.
AMS Classification: Primary 62P12; Secondary 65C05.