Mark Recapture sampling

If 50 crabs were captured and marked and then released and then a few days later 25 were caught and of those 5 were marked. What would the estimate of the population be?

• 500

• 250

• 75

• 200

Conservationists want to find the population of a species of mountain goat. On one day they capture 12 goats, tag them and release. A week later they capture 8 goats, 5 of which are tagged. What would the estimate of the population be?

• 19

• 40

• 72

• 30

Why do scientists use sampling techniques to gather population data?

• their lazy

• it is not possible to count an entire population

• it is possible to count an entire population

• they like to make estimations

If I wanted to know how many blades of grass are inside the track, which sampling method could I use?

• count every blade of grass

• Mark a random number of blades of grass, return two days later and recapture the blades

• Divide the grassy area into 1 inch sections, randomly pick several sections to count, average them together and multiply that by the total square inches.

Which of the following accurately describes the difference between mark recapture and quadrat sampling?

• Quadrat sampling is used for mobile populations and mark recapture is used for stationary populations

• Quadrat sampling is used for stationary populations and mark recapture is used for mobile populations

• Quadrat sampling can only be used for small populations

• Mark recapture sampling can only be used for small populations