18 
A. K. MORISON AND J. R. ANDERSON 
Series) and dates of sampling at the 50 sites sam¬ 
pled (Figs 1 and 2) are given in the Appendix. 
On 26 January 1989 and 21 March 1990 
single-wing fyke nets (mesh size 25 mm and 
funnel opening 200 mm) were used in Koetong 
Creek (site 31). During the more intensive sur¬ 
vey between 23 March and 1 June 1990 a shore- 
mounted, pulsed DC electrofisher (H. Riddle 
1KWC model) powered by a Honda portable 
generator (model EG 1900X, maximum output 
1.9 KVA) was used. At most sites, a stream sec¬ 
tion about 100 m long was sampled; shorter 
sections were sampled when access was limited 
or a large number of fish were caught. We maxi¬ 
mised our chances of finding populations of G. 
brevipinnis by sampling small streams with 
rocky substrates, often in the headwaters of 
catchments, although ease of access also deter¬ 
mined eventual sampling sites. 
Descriptions given by McDowall (1980a), 
Cadwallader & Backhouse (1983) and Merrick 
& Schmida (1984) were used to identify speci¬ 
mens, but all Galaxias specimens and a repre¬ 
sentative sample of other native species were 
preserved for confirmation of identity. Speci¬ 
mens were fixed in 10% neutralised formalin for 
a minimum of 3 days and then transfered for one 
day to 40% ethanol, then to 60% ethanol, and 
finally they were preserved in 70% ethanol. The 
standard length of each preserved G. brevipinnis 
specimen was measured to the nearest 1 mm 
with dial callipers, and weights of whole fish and 
their gonads were measured to the nearest 0.01 g 
on a Mettler PE3600 digital balance. The gonads 
of each G. brevipinnis specimen were examined 
macroscopically and their maturity stage was 
estimated according to the scheme used by 
Humphries (1989): Stage I, virgin; Stage II, re¬ 
covering spent; Stage III, developing; Stage IV, 
mature; Stage V, ripe; Stage VI, spent. As a 
further indication of the stage of gonad develop¬ 
ment, the gonadosomatic index (GSI) was calcu¬ 
lated as weight of gonad/total weight of fish x 
100. Maximum oocyte diameters were meas¬ 
ured with an eyepiece micrometer on a Zeiss 
stereomicroscope at 40 x magnification. Data on 
size and reproductive condition of female G 
brevipinnis collected at sites surveyed durin* 
21-30 March were combined, as were data on 
females collected during May 1990. Data on size 
and reproductive condition of males collected 
during 23-29 March 1990 were combined, as 
were those for males collected during 28 May -1 
June 1990. 
The number of vertebrae, excluding hypural 
centra, of G. brevipinnis from north-eastern Vic¬ 
toria were counted on x-ray negatives taken of 
the preserved specimens in the Ichthyology De¬ 
partment, Museum of Victoria. The significance 
of differences in these vertebral counts among 
populations of G. brevipinnis was tested using a 
single factor analysis of variance followed by a 
Newman-Keuls multiple range test (Zar 1974). 
Data for other populations of G. brevipinnis \n 
Australia were obtained from McDowall & 
Frankenberg (1981, Table 1). Only populations 
with data from 10 or more specimens were used 
in the analysis. 
To test whether the frequencies of occurrence 
of G. brevipinnis, G. olidus and S. trutta were 
independent of each other, we tested 2x2 con¬ 
tingency tables by using the chi-square test with 
the Yates correction for continuity (Zar 1974). 
Information on the known distribution of G. 
brevipinnis , records of other species of Galaxias 
from the survey area, and locations surveyed in 
the past were obtained from Tunbridge (1978), 
McDowall Sc Frankenberg (1981), Cadwallader 
& Backhouse (1983), Brumley et al. (1987), and 
Koehn Sc O’Connor (1990). In addition, the col¬ 
lections of the Australian Museum, Sydney, and 
the Museum of Victoria, Melbourne, were 
checked for all records of Galaxias species in the 
upper Murray, Kiewa, upper Murrumbidgee 
and upper Snowy River catchments. Unpub¬ 
lished records from surveys by the Victorian 
Fisheries Division (Baxter 19 8 5, 198 8, 1989, 
1990 and pers. comm., and Cadwallader pers. 
comm.) were also checked. 
All preserved specimens of G. brevipinnis anti 
Date 
Sex 
Standard Length 
(mm) 
mean range 
Maturity Stage 
(n) 
II III IV Total 
mean 
GSI 
(%) 
range 
Max. Oocyte 
Diameter (mm) 
mean range 
21-30 March 
Females 
98 
78-137 
2 
0 
10 
12 
11.6 
0.28-18.8 
1.10 
0.08-1.40 
28-31 May 
Females 
124 
85-150 
2 
3 
0 
5 
0.61 
0.36- 0.99 
0.37 
0.16-0.76 
23-29 March 
Males 
89 
75-114 
0 
1 
6 
7 
11.4 
4.32-17.3 
28 May-1 June 
Males 
86 
67-113 
3 
1 
2 
6 
3.59 
0.14-11.8 
Table 1. Size and reproductive condition of female and male G. brevipinnis collected between 21 March and 
1 June 1990. 
