Synopsis of Biological Data on the Chum Salmon, Oncorhynchus keta

feInales were no longer attended by Inales and
passively guarded the redd s. Strekalova (1963)
reported that feInales guarded the redds 1 to 6
days (average 3 to 4 days) after depositing
their eggs in the My River, U.S.S.R.
Egg retention (table 15) has not generally
been considered aniInportant cause <strong>of</strong> egg loss.
SeInko (1954) presented data to show that egg
retention can increase when spawning density
is high:
Year Eggs retained per female Total eggs deposited 6
1947
1948
1949
1950
290
45
20
28
68,280
16,050
3,730
2,940
Lister and Walker (1966) also reported an
increased egg retention (24.5 percent) in a
year <strong>of</strong> relatively high spawning density in the
Big QualicuIn River, British ColuInbia.
6 The size <strong>of</strong> area in which these eggs were deposited
was not given.
22
(g) Front view <strong>of</strong> spawning act which lasted
5 to 10 seconds. The act was repeated until
the female had ejected all <strong>of</strong> her eggs.
(h) Female covered the eggs after spawning,
Eggs have been spawned at depths <strong>of</strong> 12 to 35
CIn. below the surface <strong>of</strong> the gravel (Kuznetsov,
1928; Myren, WilliaInson, and Olson, 1959;7
Vasilev, 1959). These eggs were deposited in
two to four pockets which were parallel with
the current. One egg pocket was 7.6 CIn. deep
and 15.2 CIn. wide; the eggs were mixed with
coarse sand and gravel rather than in a COInpact
cluster [Myren, et al., 1959 (s ee footnote
7)].
As reported by Kuznetsov (1928), redds <strong>of</strong>
autUInn chuIn sa1Inon were 125 to 320 cIn.10ng
and 106 to 213 CIn. wide. The redd area averaged
1.3 In.2 for SUInIner chuIn sa1Inon in one
Asian streaIn (Vasilev, 1959), and 2.3 In.2 for
autUInn chuIn salInoninfour sInall NorthAInerican
streaInS (Burner, 1951).
7 Myren, R. T., R. S. Williamson, and J. M. Olson. 1959.
Salmon survival investigations. U.S. Fish. Wild!. Serv.,
Bur. Commer. Fish., Alaska Region (Juneau), Operations
Rep. - July I, 1958 to Feb. 3, 1959, with notes on 1957
studies. 44 pp. (Processed.)