51813_Sturgeon biodioversity an.PDF

Figure 2.Acipenserid fishesof theAmur River: a -
the head of kaluga. H. dauricus,d - ventral surface of the head of a kaluga/Amur sturgeon hybrid, and e - ventral surface of the head of
Amur sturgeon,A. schrenckii.Note difference in head and mouth shape ofH.dauricusandA. schrenekii.

kaluga,Huso dauricus, b -Amur sturgeon, Acpenser schrenckii,c-ventral surface of

of measuring morphological characters and deter-
mining age were used (Romeis 1954, Pravdin 1966).

is 48 km long and I6 km wide at the mouth of the

river. The Amur River is 4092 km long if its longest

tributary, the Shilka River, is included. The total

size of the basin is 1 856 000 km^2. For much of its

length, it forms the border between Russia and Chi-

na.

According to the structure of its valley, bed and

flow characteristics, the Amur River can be divided

into three parts (Figure 1). The upper reach of the

General characteristics of the Amur River

The Amur River is formed by the confluence of the

Argun and Shilka rivers (Figure 1). It enters into the

Amur estuary of the Tatar Strait. The Amur estuary