7.2
9
The simplest method for assessing the international value of a site for waterfowl is by considering the total number of waterfowl which occur there. If this exceeds an agreed level, the site can be regarded as internationally important.
7.3
Analysis of over 10,600 ring returns of ducks ringed in the U.S.S.R. has enabled workers there to suggest relationships between breeding populations and wintering areas (Isakov and Shoverava 1958, Sheverava 1970). Isakov (1970) has provided estimates of the numbers Russian or Siberian-bred waterfowl occuring in the four westermost flyways and Kistchinski (1973) has provided a summary of information concerning the distribution and numerical status of waterfowl in northeast Asia.
2.4
Hong Kong would appear to lie somewhere on the border of the East Siberian - Tibet Ganges flyway* and the Amur - Chinese flyway. There is virtually no information concerning these flyways. As far as is known, no wildfowl surveys have been conducted in Chine and there is no information available regarding breeding or wintering numbers. Thus unfortunately it is not possible to assess the importance of the Marshes in an international context in relation to the number of birds present.
8. Summary
8.1
The Marshes contain the largest and most important area of dwarf mangrove in Hong Kong. This highly productive seral community and the related man made kei wais provide a rich food source for both resident and migratory birds, as well as nesting habitats for a number of species. The Marshes are the only area in Hong Kong where large numbers of duck, shore and marsh birds can regularly be seen and, as such, have a very considerable recreational and educational potential. At present this potential
is completely neglected. Possible ranagement plans for developing this potential are given in Part II.
*
Foot note: A flyway is a well defined migration route
linking specific breeding and wintering grounds.