FRESHWATER FISH IN THE OTWAY REGION 
35 
sidered to be under some threat (Cadwallader 
et al. 1984). 
The fish species with the greatest conservation 
need in the Otway region is the Australian gra¬ 
yling. This species was classified by Cadwallader 
et al. (1984) as “vulnerable in Victoria” but is 
likely to be considered endangered in the near 
future if the population continues to decline. 
Australian grayling were collected from nine 
sites in the study area, most of the samples con¬ 
sisting of a few young individuals taken from 
coastal streams. More than 100 Australian gray¬ 
ling have been taken from a population moni¬ 
tored in the Barwon River (Hall & Tunbridge 
1988, Jackson & Koehn 1988). The collection of 
Australian grayling whitebait ascending the 
Cumberland River adds to our knowledge of the 
lifecycle of this species. The Otway region 
should be considered an important conservation 
area for this species because of its widespread 
distribution in coastal streams. 
The broad-finned galaxias, the spotted gal- 
axias and the Tasmanian mudfish were all listed 
by Cadwallader et al. (1984) in Category C; that 
is, species that are rare or have a restricted distri¬ 
bution in Victoria. Broad-finned and spotted 
galaxias were widespread and abundant in the 
Otway coastal streams. The Tasmanian mudfish 
was first found on mainland Australia at 
Wilsons Promontory (Jackson & Davies 1982). 
Discovery of a specimen in Wye River in 1983 
extends the known range of the species into 
western Victoria. The swamp areas normally 
inhabited by adults of this species pose sampling 
difficulties, and a study of the whitebait stage 
(Fulton 1986) may determine other localities. 
The conservation status in Victoria of the 
pouched lamprey, which was recorded at six 
sites, has been listed as “indeterminate”, i.e. 
possibly threatened (Category' D of Cadwallader 
etal. 1984). 
Because the fish fauna of the Otway coastal 
streams consists of species which need to 
migrate between the sea and fresh water at some 
stage of their lifecycles, the maintenance of fish 
passage in these streams is important. Passage of 
many species into the upper reaches of several 
streams is restricted by natural barriers such as 
waterfalls. Only short-finned eels and broad- 
finned galaxias occur naturally above such bar¬ 
riers, an indication of the extraordinary climb¬ 
ing and migratory' capabilities of these species. 
Most other species are much more restricted by 
stream barriers and are thus more easily cut off 
from available habitat by small weirs or cul¬ 
verts. 
The native freshwater species most widely 
sought by anglers in southern Victoria is the 
freshwater blackfish (Barnham 1983). One of 
Victoria’s most valuable populations of this spe¬ 
cies is found in the Gellibrand River which has 
the highest reported percentage of freshwater 
blackfish longer than the minimum legal length 
(220 mm TL). This river is one of the few that 
still contain large specimens of this species (Tun¬ 
bridge & Glenane 1988). 
Not surprisingly, the Gellibrand River is one 
of the most popular freshwater fishing venues in 
Victoria. Most anglers (76%) on the Gellibrand 
River seek freshwater blackfish (Koehn 1984) 
and are attracted by the prospect of catching a 
trophy fish. The range of this species has been 
considerably reduced (Jackson & Llewellyn 
1980) and the Gellibrand River needs to be 
given a high level of protection. Careful land 
management and the provision of adequate buf¬ 
fer strips are required to avoid the heavy sedi¬ 
mentation seen at two sites. 
The Gellibrand and Barwon Rivers are classi¬ 
fied as sport fisheries for the freshwater black¬ 
fish (Tunbridge & Glenane 1983), and streams 
in the Otway region provide many opportunities 
for anglers seeking brown trout. Large numbers 
of brown trout of suitable size were present at 
most of the sites we sampled and, despite de¬ 
creases in stockings, most streams have viable, 
self-maintaining populations of this species. 
The Otway region contains a valuable assem¬ 
blage of mainly native freshwater fish and the 
introduction of other species should be pre¬ 
vented. The region provides excellent conser¬ 
vation areas for many fish species in addition to 
opportunities for recreational angling for 
freshwater blackfish and brown trout. Most of 
the streams maintain riparian vegetation, 
instream cover and substrate free of silt, all attri¬ 
butes which have been lost from many river 
systems. If these valuable fish faunas and their 
habitats are to be retained, careful management 
is needed. 
ACKNOWLEDGEMENTS 
We thank John McKenzie and Des Harrington 
for their assistance in field surveys; Wayne 
Fulton and Roger Frankenberg for assistance in 
species identification; Darwin Evans and Jim 
Bowler for comments on the manuscript; Ruth 
Lawrence, Justin O’Connor and Damien 
O’Mahony for proof reading; and Martin Batt 
for drafting assistance. 
