1. Estimating Population Size Using Mark and Recapture

2. Estimating Population Size
Integral part of population dynamics
Helps ecologists see changes over time

4. Estimating Mobile Organisms
How would you estimate a population of mice?

5. Mark & Recapture Common method used by ecologists
Steps: capture, mark, release, recapture
Assumptions: closed population
Several samples taken over a short period

6. Marking Methods

7. Lincoln Index
Statistical measurement that estimates population size based on mark and recapture
N1 x N2 R
size of first sample
size of second sample
P =
size of population
# of recaptures in second sample

9. Biogeochemical News
Chemical Cycles
How humans effects