Which index is used to measure the abundance of motile organisms?

The Lincoln Index is specifically designed for estimating the population size of motile organisms, making it the most suitable choice for this question. This index operates on the principle of capture-recapture, where a sample of individuals from a population is captured, marked, and then released. After a period of time, another sample is taken, and the number of marked individuals in this second sample is used to estimate the total population size.

By tracking how many individuals are captured multiple times, researchers can make inferences about the abundance and distribution of motile organisms in an ecosystem. This method is particularly effective because it accounts for the movement of organisms, which is a critical factor when studying species that do not remain static in their environment.

Other indices mentioned do not focus specifically on measuring abundance in motile organisms. The Simpson's Index of Diversity is more focused on the diversity and evenness of species within a community rather than absolute numerical abundance. The Trophic Level Index deals with the positions organisms occupy in food webs rather than their population counts. The Population Density Index might seem related but typically focuses on density per area rather than employing the dynamic method of capture-recapture. Thus, the Lincoln Index stands out as the most appropriate for assessing the abundance of motile organisms