Capture-recapture

• Capture-recapture -> to estimate the population size of an animal species
• Method:

  1. go to the area for a set amount of time and capture as many of the animal as you can
  2. mark them and release them
  3. go back at a later date and capture as many animals as you can. Note how many were recaptured
  4. use the formula
• Number captured in first sample x number captured in second sample divided by number recaptured
• To consider:

  • cannot mark an animal in a way that would affect their chance of survival (marking shouldn’t be visible)
  • we assume no animals have died between samples
  • we assume no animals have emigrated out of the area between samples