Population

Question 1

N = MC/R

Answer 1

N = Estimate of total population size
M = Total number of animals captured and marked on the first visit
C = Total number of animals captured on the second visit
R = Number of animals captured on the first visit that were then recaptured on the second visit

Question 2

Mark release recapture

Answer 2

Trap the species
Mark them (doesn’t interfere with the chances of survival)
Release
Recapture

Question 3

What are the sources of error for mark release recapture?

Answer 3

• The proportion of marked to unmarked animals is the same in the second sample as in the populations as a whole
• The marked individuals have sufficient time
to redistribute themselves evenly
• The population has a definite boundary
• Few births and deaths in the time period
• The mark is not lost or rubbed off

Question 4

Ethical issues for mark release, recapture

Answer 4

• The marking method is not toxic
• The mark does not make the animal more conspicuous to predators
• The capture and marking method is not harmful or overly stressful to the animal.