TLS Online TPP Program

#Question id: 10631


To estimate the number of foxes m an area, a researcher conducted a mark-recapture survey. In the fast survey, he caught and marked 90 foxes. In his second survey a week later, he caught 120 foxes of which 40 were marked (recaptures). If you are told that the actual number of foxes in this area is 400, which of the following is a plausible explanation for the anomaly in the researcher's data? 

#Section 1: Ecology
  1. Capture increased mortality in the marked foxes
  2. Large mortality of foxes between the two surveys 
  3. The marked foxes were more likely to avoid recapture
  4. The marked foxes were more likely to be recaptured