For which of the following cases, population density can be easily determined by utilising non-biological parameter ?

Options

A. Fish density
B. Density of bacteria in culture plate
C. siberian of cranes at Bharatpur wetlands
D. Tiger census

Answer

To determine which case allows for population density to be easily assessed using a non-biological parameter, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Population Density**: Population density refers to the number of individuals of a species per unit area or volume. It can be measured in absolute terms (exact count) or relative terms (estimates based on sampling).

2. **Identify Biological vs. Non-Biological Parameters**: Biological parameters involve direct counts or measurements of living organisms, such as counting individuals or their reproductive output. Non-biological parameters are indirect measures, such as footprints, fecal matter, or other environmental indicators.

3. **Evaluate the Options**: Review the given cases to see how population density is determined in each:
- **Fish Population**: Density is often measured by counting the number of fish caught in traps (biological parameter).
- **Bacteria**: Density is assessed through colony counts or estimates from samples (biological parameter).
- **Siberian Cranes**: The population can be counted directly (biological parameter).
- **Tiger Census**: This is typically done by counting pug marks and fecal pellets instead of directly counting tigers (non-biological parameter).

4. **Conclude the Case**: Among the options, the tiger census is the only case where population density can be determined using a non-biological parameter (pug marks and fecal pellets).

### Final Answer:
The case where population density can be easily determined by utilizing a non-biological parameter is the **Tiger Census**.

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