Quantitative survey of a named animal using capture-recapture method

The 'Capture-Recapture Method' is used for a quantitative survey of a named animal e.g. snail.

Set up the animal collection method in advance, such as a pitfall trap, as described previously.

Day 1

1. Collect as many of the chosen animal (e.g., snails) as possible using the appropriate equipment pitfall trap.
2. Record the number captured (e.g., 10 snails).
3. Mark each animal using a suitable, non-toxic marker without causing harm (e.g., mark the underside of the snail's shell with non-toxic paint, avoiding areas that might attract predators).
4. Replace all marked animals back into the habitat and reset traps.

Day 2

1. Collect the snails using the same method as the method used on day 1.
2. Record the number captured (e.g., 15 snails).
3. Record the number of marked snails captured (e.g., 5 marked animals).
4. Return all animals to their habitat. Calculation:

$$\frac{(𝑛𝑢𝑚𝑏𝑒𝑟\ 𝑐𝑎𝑝𝑡𝑢𝑟𝑒𝑑\ 𝑑𝑎𝑦\ 1)\ X\ (𝑛𝑢𝑚𝑏𝑒𝑟\ 𝑐𝑎𝑝𝑡𝑢𝑟𝑒𝑑\ 𝑑𝑎𝑦\ 2) }{𝑛𝑢𝑚𝑏𝑒𝑟\ re𝑐𝑎𝑝𝑡𝑢𝑟𝑒𝑑\ 𝑡ℎ𝑎𝑡\ 𝑤𝑒𝑟𝑒\ 𝑚𝑎𝑟𝑘𝑒𝑑}$$

Example**:**

$$\frac{10\ X\ 15}{5}=:highlight[30]$$