A minimum estimate of the overall population
size of the Hong Kong/PRE humpback dolphin
population can be derived by adding the estimates
for individual areas. The highest such estimate,
1,504 animals, occurred in the winter season (see
Figure 3; Jefferson, 2002). This estimate must be
considered somewhat preliminary, however, due
to the high coefficients of variation for some areas
and seasons. The large variation among estimates
for different seasons suggests that some dolphins
move out of the study area, especially in summer
months, and, therefore, that we still have not surveyed
the entire range of the population. Survey
work continues and we will update these analyses
in the future.